Thèses : « Ruminant feeding »

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McGill, Tyler R. « Improving the Efficiency of Dairy Cattle Feeding ». Thesis, Virginia Tech, 2017. http://hdl.handle.net/10919/79951.

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Biological functions that use amino acids (AA) are limited by AA supply. This concept was likened to staves in a barrel, where the shortest stave determines the barrel's ability to hold water (Mitchell and Block, 1946). Inaccuracies in models that predict nutrient supply and requirements of dairy cows result in inefficient feeding, as under-prediction of requirements results in deficiency, and over-prediction results in excess. To avoid limitations in production due to AA deficiencies, protein is fed in quantities that likely exceed requirements. Overfeeding of AA results in increased expenses for producers and increased N excretion to the environment, providing economic and environmental incentives to increase N-efficiency. Work presented in the following chapters evaluated the impact of AA supplementation on milk production in dairy cattle, and evaluated the PREP10 and NRC (2001) nutrient requirement model predictions. In two feeding trials (Chapter 2 and Chapter 3), low protein diets did not result in decreased milk production, indicating that protein requirements were overestimated. Although supplementation of AA did not increase milk production, low protein diets resulted in greater N-efficiency, especially when supplemented with Histidine. Evaluation of the PREP10 and NRC (2001) models (Chapter 4) used production data from the literature to identify deficiencies in prediction equations, and found that correction of model bias would considerably reduce prediction errors. Model inaccuracies affect the inefficiency of dairy cow feeding, and must be evaluated to improve feed efficiency. Such improvements could act synergistically with AA supplementation to more closely match nutrient supply to requirements.
Master of Science

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Osman, T. E. A. A. « Reticulo-ruminal motility and food intake in sheep ». Thesis, University of Liverpool, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.383451.

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Campidonico, Luca. « Plant secondary compounds in ruminant feeding : implication and effect on meat fatty acid ». Doctoral thesis, Università di Catania, 2017. http://hdl.handle.net/10761/3776.

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According to FAO, about 9 billion of people will ask for food by 2050. The agriculture challenge is to increase food production by preserving food quality and natural resources. According to WHO, red meat can favor the onset of cardiovascular disease and colon-rectal cancer; however, they are also an important source of vitamin, protein and functional fatty acids (CLA, EPA, DHA). Future animal breeding techniques aims will be improving food nutritional profile and reducing environmental impact at the same time. Rumen lipolysis and bio-hydrogenation allow the synthesis of a pool of fatty acids; this process is affected by animal diet. Pasture feeding increase omega-3 and CLA content in food; however, the problems related to pasture availability ask for innovative techniques that promote their synthesis even if green herbage is not present. The use of plants, or plant-extracts, containing bioactive compounds represents an achievable prospect. The aim of this PhD was to deepen how different plants bioactive compounds affect fatty acid composition in lamb meat. In the first experiment, the use of Trifolium pratensis (containing polyphenol oxidase enzyme, PPO) and Onobrychis viciifolia (containing condensed tannins, CT) silages were tested. The effect of PPO and CT on rumen lipid profile was comparable and even additive when silages were supplied as a mixture. In this case, meat fatty acid profile was similar to pasture-fed animals. In the second experiment, three plants extract were added to lambs diet: hydrolizable tannins from chestnut (Castanea sativa), CT from mimosa (Acacia dealbata) and from gambier (Uncaria gambir). The effect of the different source of tannins on meat fatty acid composition was not very strong; however, multivariate analysis allowed discriminating the different groups.

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Njogah, John Njihia. « Ammoniation of low quality roughages using urea to improve their nutritive value for ruminant feeding ». Thesis, University of British Columbia, 1989. http://hdl.handle.net/2429/27604.

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This study was carried out to examine the effect of urea treatment on different roughages with respect to their degradation in the rumen. The effect of urea treatment of barley straw on dry matter intake, digestibility and weight gain was also studied. The first experiment involved urea treatment of wheat straw and orchardgrass hay. Three urea levels were used; 2, 4 and 6 g/100 g DM and the samples ensiled for 3, 6 and 9 weeks. Samples were incubated in the rumen for 1, 12, 24, 36, 48, 72 and 96 hours. Degradation constants were derived using the equation p = a + b(1 – e[sup –ct]) where 'p' represents the amount degraded at time 't'. 'a' represents the fraction which disappears rapidly, 'b' represents that fraction which will degrade in time and the rate of degradation of this fraction is represented by the 'c'. The fraction which is undegradable in the rumen can be derived as 100 - (a + b) . Orchardgrass hay had significantly larger degradation constants than wheat straw (P<0.05). Treatment increased the rapidly disappearing-'a' fraction of wheat straw but reduced the same fraction of orchardgrass hay (P<0.05). The 'b' fraction of orchardgrass hay was increased significantly (P<0.05) by urea treatment; in the case of wheat straw, the increase was not significant (P>0.05). Crude protein content of both materials was increased by treatment (P<0.05). Rumen disappearance of CP did not show a consistent trend especially in the case of control samples and this was an indication of microbial contamination of the residue in the bags. In other words, part of dry matter that remained in the bags was contributed by microbial material. Such material also contributed to the nitrogen content of the residue thus masking some of the crude protein disappearance that may have occurred. In the second experiment, some of the crop by-products that are fed to ruminants in Kenya, were treated. These included barley straw, maize stover, oat straw, rice straw, wheat straw and rhodesgrass hay which was considered to be of low quality. Water was added to raise the moisture content of the materials to 20%. Urea was applied at 6 g urea/100g DM and the materials were ensiled for 6 weeks. Samples of the ensiled materials and their controls were incubated in the rumen of a cannulated steer for 1, 12, 24, 36, 48 and 72 hours. Also incubated were untreated samples of napier grass, alfalfa hay and pyrethrum marc. Rhodesgrass hay had the largest degradation constants ('a', 'b' and :a+b') before treatment and barley had the least; 13.59, 61.63, 75.22 and 7.16, 37.71, 44.87% respectively. Treatment had the largest impact on rice straw; the 'a', 'b' and 'a+b' increased from 10.24, 46.27 and 56.51% to 22.11, 70.79 and 92.91% respectively. In the case of rhodesgrass hay, treatment had no significant effect (P>0.05). Urea treatment increased significantly (P<0.05) the CP content of all materials. Analysis of data for CP disappearance indicated microbial contamination and this was more evident in the control samples where 24 and 72 hours incubation left the samples with more CP than the unincubated samples. Most of the CP in low quality roughages is bound to the lignin and is therefore undegrable. As degradation proceeds, the CP progressively becomes a larger fraction of the total dry matter which undergraded, thus there is a concentrating effect. In the final experiment sixteen calves weighing from 86 to 176 kg were divided into four weight categories. Animals within the same weight category were randomly allocated to four different diets; barley straw treated with 4 or 6 g urea/100g DM and ensiled for six weeks; or urea added to straw at feeding time to raise the crude protein to the levels in the ensiled straws. The straws were mixed with hay in 3:1 ratio (straw:hay) and offered ad libitum. In addition each calf received 1.5 kg of concentrate plus 20 g of a mineral mixture daily. A randomized complete block design was used and each group was on diet for four weeks after which the groups were randomly re-assigned to different diets. Treatment did not improve dry matter intake significantly (P>0.05). Acid insoluble ash (AIA) was used as an internal marker to calculate apparent digestibilities for DM, CP and ADF. Straw treated with 6 g urea/100g DM and ensiled had a higher dry matter digestibility (P<0.05) than the other straws; there was a 16.3% improvement over control. Ensiling reduced CP digestibility significantly (P<0.05). Acid detergent fibre digestibility was improved in the case of straw treated with 6 g urea/100g DM and ensiled compared to the control. There were no significant differences between the different diets in terms of average daily gain but there was a trend towards higher gain as the level of urea increased. Urea as a source of ammonia for the treatment of low quality roughages has given encouraging results and is emerging as a viable treatment method. The method has some advantages over other chemicals in that it is safer to handle, cheaper, readily available and involves simple treatment procedures.
Land and Food Systems, Faculty of
Graduate

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Useni, Bilungi Alain. « Effect of exogenous fibrolytic enzymes on fibre and protein digestion in ruminant animals ». Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/6744.

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Thesis (MScAgric (Animal Sciences))--University of Stellenbosch, 2011.
Includes bibliography.
ENGLISH ABSTRACT: Forages are the main feed components in ruminant production systems for the reason that they are often the major source of energy available to the animal. However, only 10 to 35% of energy intake is available as net energy because the digestion of plant cell walls is not complete. This can significantly affect livestock performance and profits in production systems that use forages as a major source of nutrients of the diet. As a result of low and variable nutritive values of forage feedstuffs, attempts to improve ruminal fibre degradability have been an ongoing research topic. The use of exogenous fibrolytic enzymes (EFE) has been proposed as means to improve forage digestibility. Positive results with regard to rumen forage digestibility and other animal production traits have consequently been obtained due to increased rumen microbial activity following EFE addition in ruminant diets. Two EFE (Abo 374 and EFE 2) and one commercial yeast preparation were firstly identified and selected for their potential to improve the cumulative gas production (GP) at 24 hours of a range of feed substrates using the in vitro GP system as a screening step to identify the superior EFE products. The different feed substrates were lucerne hay, wheat straw, wheat straw treated with urea and a commercial concentrate diet. An in vitro experiment was undertaken on these four different substrates in order to evaluate the two EFE and the yeast preparation. This was to identify the most promising EFE capable of producing a significant effect on feed digestibility using organic matter digestibility (in vitro true digestibility) and fermentation characteristics (in vitro GP system). Results from the in vitro evaluation showed that EFE significantly enhanced in vitro DM degradability and GP profiles (P < 0.05). Abo 374 enzyme showed potential to increase in vitro microbial protein synthesis (MPS) of GP residues of the concentrate diet. In addition, no correlation was found between the in vitro MPS and the 48 hours cumulative GP of all the tested substrates (P < 0.05; R2 < 0.30). Treatments were found to increase in vitro MPS, feed degradability and the cumulative GP of different quality forages and the concentrate diet, with Abo 374 being the best treatment (P < 0.05). However in vitro responses of EFE were variable depending on the energy concentration and chemical composition of different substrates. Variation in MPS was mostly due to the low recovery of purine derivates with the purine laboratory analysis. On the basis of these results, Abo 374 was selected and consequently further tested in another in vitro and in situ trial using a mixed substrate of lucerne hay and wheat straw. Abo 374 significantly improved the cumulative GP, in vitro DM and NDF disappearance of the mixed substrate (P < 0.05). In addition, no correlation was found between the in vitro MPS and the cumulative GP at 48 hours (P = 0.68; R2 < 0.25). The in situ disappearance of feed nutrients (DM, NDF and CP) with Abo 374 was similar to the control. The lack of significance of disappearance was probably due to the small number of sheep used in the study and the relatively high coefficient of variation associated with measuring ruminal digestion. Abo 374 significantly increased the in situ MPS (P = 0.0088) of the mixed substrate of lucerne hay and wheat straw. Evidence of the increased MPS and both in vitro and in situ disappearance of DM and NDF resulted from the Abo 374 activity during either the pre-treatment or the digestion process. The addition of Abo 374 to the mixed substrate of lucerne hay and wheat straw appeared to have been beneficial for microbial colonization of feed particles as a result of the increased rumen activity. It could be speculated that the primary microbial colonization was thus initiated, leading to the release of digestion products that attract in return additional bacteria to the site of digestion. This EFE may be efficient to produce some beneficial depolymerisations of the surface structure of the plant material and the hydrolytic capacity of the rumen to improve microbial attachment and the feed digestibility thereafter. Therefore, the mechanism of action by which Abo 374 improved the feed digestion can be attributed to the increased microbial attachment, stimulation of the rumen microbial population and synergistic effects with hydrolases of ruminal micro-organisms. With regard to these findings, the addition of EFE in ruminant systems can improve the ruminal digestion of DM, NDF and CP to subsequently enhance the supply of the metabolizable protein to the small intestine. Key words: crude protein (CP), exogenous fibrolytic enzymes (EFE), dry matter (DM), gas production (GP), neutral detergent fibre (NDF), microbial protein synthesis (MPS).
AFRIKAANSE OPSOMMING: Ruvoere is die hoof-voerkomponent in herkouer produksiesisteme aangesien dit dikwels die vernaamstebron van energie aan herkouer is. Slegs 10 tot 35% van die energie-inname is beskikbaar as netto-enrgie, omdat die vertering van selwande onvolledig is. Dit kan die prestasie en profyt in produksiesisteme drasties beïnvloed waar ruvoere as ’n hoofbron van nutriënte in die dieet gebruik word. Aangesien die nutriëntwaarde van ruvoere laag is en baie varieer, is navorsing vir verbeterde ruminale veselvertering steeds ’n voorgesette onderwerp. Dit is voorgestel dat eksogeniese fibrolitese ensieme (EFE) gebruik kan word vir verbeterde ruvoervertering. Positiewe resultate in ruminale ruvoerverterig en ander diereproduksie-eienskappe, is verkry as gevolg van toenemende rumen mikrobiese aktiwiteit na EFE aanvulling in herkouerdiëte. Twee EFE’s (Abo 374 en EFE 2) en `n gisproduk is geïdentifiseer en geselekteer vir hul potensiaal om die kumulatiewe gasproduksie (GP) na 24 uur met ’n reeks voersubstrate te verbeter met die gebruik van die in vitro GP sisteem as seleksiemetode om die superieure EFE produkte te identifiseer. Die verskillende ruvoersubstrate was lusernhooi, koringstrooi, ureumbehandelde koringstrooi en ’n kommersiële konsentraatdieet. ’n In vitro eksperiment was onderneem om die vier verskillende substrate te gebruik om die twee EFE’s en gisproduk te evalueer. Hierdeur sou die belowendste EFE’s identifiseer kon word wat ’n betekenisvolle effek op ruvoervertering het. Die vertering van ruvoer sal bepaal word deur organiese materiaal vertering (in vitro ware vertering), asook fermentasie-eienskappe (in vitro GP sisteem). Resultate van die in vitro evaluering het getoon dat EFE’s in vitro DM degradering en GP profiele verbeter. Dit blyk dat die Abo 374 ensiem ’n potensiële toemame in in vitro mikrobiese proteïensintese (MPS), soos bepaal deur die GP oorblyfsels van konsentraat diëte, tot gevolg gehad het. Daar was geen korrelasie tussen die in vitro GP en MPS van al die proefsubstrate nie. Dit blyk dat die behandelings ’n toename in in vitro GP, MPS en ruvoerdegradeerbaarheid van lae kwaliteit ruvoer- en konsentraatdiëte gehad het, waar Abo 374 die beste behandeling was. Die in vitro reaksies van die EFE’s was egter wisselend, afhangende van die energiekonsentrasie en die chemiese samestelling van die verskillende substrate. Variasie van MPS was meestal as gevolg van die lae herwinning van purienderivate tydens die purienanalise. Op grond van dié resultate, is Abo 374 geselekteer om verdere toetse in ander in vitro en in situ proewe te doen. Die substraat wat gebruik is, was ’n 1:1 mengsel van lusernhooi en koringstrooi. Abo 374 het die kumulatiewe RP, in vitro DM en NBV verdwyning van die gemengde substraat verbeter. Boonop is geen korrelasie tussen die MPS en in vitro GP gevind nie. In situ verdwyning van DM, NBV en RP was hoër vir Abo 374, maar nie betekenisvol nie. Die gebrek aan betekenisvolle verdwynings mag die gevolg wees van die klein hoeveelheid skape wat in die proef gebruik is, asook die relatiewe hoë koëffisient van variasie wat gepaard gaan met die bepaling van ruminale vertering. Abo 374 het die in situ MPS betekenisvol verhoog. Verhoogde MPS en in vitro en in situ verdwyning van DM en NBV is waargeneemwaarskynlik as gevolg van die aktiwiteit van Abo 374 gedurende die voorafbehandeling óf die verterings proses. Die byvoeging van Abo 374 tot die gemengde substraat van lusernhooi en koringstrooi blyk om voordelig te wees vir mikrobiese kolonisering van voerpartikels as gevolg van ’n toename in rumenaktiwiteit. Die primêre mikrobiese kolonisering het waaarskynlik gelei tot die vrystelling van verteringsprodukte wat addisionele bakterieë na die plek van vertering lok. Die EFE mag geskik wees vir voordelige depolimerisasie op die oppervlakstruktuur van die plantmateriaal, asook verbeterde hidrolitiese kapasiteit van die rumen om sodoende mikrobiese aanhegting, asook ruvoervertering te verbeter. Dus, Abo 374 se meganisme van aksie wat verbeterde ruvoervertering tot gevolg het, kan toegeskryf word aan `n verhoogde mikrobiese aanhegting, stimulering van die rumen mikrobiese populasie en die sinergistiese effek met hidrolases van rumen mikroörganismes. Ten opsigte van die bevindings, kan die byvoeging van EFE in herkouersisteme ruminale vertering van DM, NBV en RP verbeter, wat dan daaropvolgend die dunderm met meer metaboliseerbare proteïn sal voorsien. Sleutelwoorde: eksogene fibrolitiese ensieme (EFE), droëmaterial (DM), ruproteïen (RP), neutraal bestande vesel (NBV), mikrobiese proteïensintese (MPS), gasproduksie (GP).

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Mullins, Chad Ryan. « Feeding behavior and metabolism of transition dairy cows supplemented with monensin ». Diss., Kansas State University, 2011. http://hdl.handle.net/2097/13102.

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Doctor of Philosophy
Department of Animal Sciences and Industry
Barry J. Bradford
The mechanisms behind the metabolic changes observed when transition cows are administered monensin, as well as the effects of supplementing mid-lactation cows with two commercial amino acid products were investigated. Traditionally, the effects of monensin are attributed to increased gluconeogenic precursor supply, but recent research indicated that the effects of monensin extend beyond gluconeogenic flux. Thus, the primary objectives of Experiment 1 were to determine if monensin modulates transition cow feeding behavior, ruminal pH, and/or expression of key metabolic genes. Overall, monensin decreased time between meals prepartum (126 vs. 143 ± 5.0 min; P < 0.03) with a trend appearing postpartum (81.4 vs. 88.8 ± 2.9 min; P < 0.08), which could be related to the smaller ruminal pH standard deviation during the first day cows received the lactation ration (0.31 vs. 0.26 ± 0.015; P < 0.02). Monensin also increased liver mRNA abundance of carnitine palmitoyltransferase 1a (0.15 vs. 0.10 ± 0.002 arbitrary units; P < 0.04), which corresponded to a slower rate of liver triglyceride (TG) accumulation from 7 days before calving through 7 days post calving (412 vs. 128 ± 83 mg TG/g protein over this time period; P = 0.03). No significant effects of monensin supplementation were observed on other metabolic parameters or milk production. Overall, these results confirm that the effects of monensin on transition cows extend beyond altered propionate flux. In Experiment 2, mid-lactation cows consuming a control diet containing 26% wet corn gluten feed (dry matter basis) were compared to cows consuming the same diet supplemented with lysine embedded within Ca salts of fatty acids and the isopropyl ester of 2-hydroxy-4-(methylthio) butanoic acid, a methionine precursor. This trial was conducted because the NRC (2001) model indicated a lysine deficiency prior to supplementation; however amino acid supplementation had no effects. This trial was then extended to decrease dietary CP from 17.9% to 17.1%, and further increase lysine and methionine supply in the treatment diet. No production or intake effects were observed during this period, but MUN was decreased in the treated group (10.8 vs. 12.5 ± 0.2 mg/dL; P < 0.001).

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Anele, Uchenna Young [Verfasser]. « Evaluation of dual purpose cowpea varieties for dry season feeding of ruminant animals / Uchenna Young Anele ». Bonn : Universitäts- und Landesbibliothek Bonn, 2011. http://d-nb.info/1016001525/34.

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Gobindram, Mohammad Noor Ehsan Newaz. « Plant secondary compounds in small ruminant feeding in stall-fed and pastoral system in the Mediterranean ». Doctoral thesis, Università di Catania, 2015. http://hdl.handle.net/10761/1642.

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The utilization of alternative feed resources such as agro-industrial by-products or rangelands may contribute to reduce carbon footprint and improve sustainability of livestock farming systems.My thesis aimed at investigating how animals can be made to ingest alternative feed resources containing higher amounts of Plant Secondary compounds (PSCs) than usual forages and concentrates. PSCs are present in agroindutrial by products and in the natural vegetation of rangelands in the Mediterranean area. They are often associated with anti-nutritive properties such as reduced palatability and protein digestion but can also have positive effects especially on health. Two systems of lamb meat production were investigated, namely stall-fed in Siciliy and pastoral in Morocco. In the stall-fed system, we investigated the potential of replacing barley by two locally available agro industrial by- products containing polyphenols, namely carob pulp and dehydrated citrus pulp (DCP). The animals were 90 days of age Ccomisana lambs assessed during fattening. Food intake pattern and blood metabolic profile were monitored. It was found that ingestion of a diet containing 35% of carob pulp or DCP resulted in comparable performance, feed efficiency and carcass weight and yield as compared to animals ingesting a cereal based diet (control). The daily feed consumption pattern was markedly affected by the inclusion of carob pulp in the diet.Control group ate more than 40% of the whole daily intake in the first 90 min of feeding compared with only 33% in the carob groups but the overall feed intake was unchanged. The highest level of DCP inclusion in the diet also produced a different rate of feed consumption, as compared to the control group. In terms of blood metabolic profile, carob ingesting animals had lower cholesterol, higher urea and higher NEFA compared to the control whilst with DCP ingestion none of the parameters measured were affectedPertaining to the blood protein profile, carob pulp addition gave minor effects, only a tendency for the albumin to globulin (AG) ratio to rise has been observed; in the case of DCP inclusion in lambs diet, the serum albumin and the AG ratio was higher compared to the control; but the values were not a a level to cause metabolic distress.

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Walker, Keitirele Patricia. « Productivity of four fodder tree species, their nutritional value and potential role in ruminant production in Eastern Botswana ». Thesis, Stellenbosch : University of Stellenbosch, 2007. http://hdl.handle.net/10019.1/1421.

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Thesis (PhD (Forest and Wood Science))—University of Stellenbosch, 2007.
Sustainable livestock production in semi-arid Botswana could be improved through tree planting on-farm to provide much needed protein and shade. Such action can be encouraged if the growth, productivity, nutritional value of trees and their contribution to mass gain of livestock are known.. A study at Malotwana investigated two indigenous species, Acacia galpinii and Faidherbia albida, and two exotic species, Leucaena diversifolia and L. leucocephala, at three spacings in a randomised complete block design replicated five times. The three spacings represented 400, 317 and 241 trees per hectare. The study was conducted over 6.5 years. Indigenous trees were sampled biennially and exotics annually to evaluate crown width, height, stem diameter, stem number and stem volume index. Complete plant harvesting of exotic trees at 2.5, 4.5 and 6.5 years evaluated agroforestry production. Leaves from all four species and pods of exotic species were analysed for chemical composition. Two groups of eight lambs were balanced for mass at selection for an on-farm feeding trial. Browse from exotic trees, comprising a 2:1 ratio of pods to leaves, was fed at 30% as supplement to hay to one group whose mean mass was contrasted with that of the control group fed sorghum bran at 30%. A. galpinii was a promising species, adaptable to planting away from its origin. Its crown width ranged from 5.86 m in high density plots to 6.08 m at low density and was significantly different among stands (p = 0.0406) at 6.5 years. Diameter at breast height (dbh) was significantly different among stands aged 6.5 years (p = 0.0003) and ranged between 10.38 cm at high density to 12.48 cm in low density plots, demonstrating a capacity to provide both shade and poles on-farm. At 4.5 years, F. albida attained a mean height of 4.5 m and 4.5 cm in dbh but suffered 67% mortality during a severe drought. Annual fodder production of 0.647 and 0.996 metric tonnes ha-1 for leaves and pods of L. diversifolia and 1.237 and 1.431 for L. leucocephala was recorded in years of average rainfall. Yields of 0.3 and 0.59 metric tonnes ha-1 were recorded for both species in the driest year. Equally good agroforestry production was obtained from both low and high density stands suggesting that low density plantings, which foster higher plant survival and reduce disease incidence, are best suited to the semi-arid conditions of Botswana. The crude protein of leaves ranged between 16.26 (L. diversifolia) and 25.25% (F. albida). They were highly digestible with more than twice the calcium content livestock require. Crude protein and digestibility measures were significantly different among leaves and varied significantly at different spacings (p<0.0001). Pods of the exotic species contained significantly more protein than the leaves (p<0.0001). Lambs supplemented with browse gained 102.33 g per animal per day while the control group gained 83.95 g. There were significant differences between groups during growth (p<0.05). Growing of A. galpinii, complemented with L. diversifolia and L. leucocephala, can supply short and long term feed, and greatly enhance livestock production while diversifying farm feed sources

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Gravador, Rufielyn. « Plant secondary compounds in small ruminant feeding : an alternative to synthetic compounds for improving meat quality in low-input farming systems ». Doctoral thesis, Università di Catania, 2015. http://hdl.handle.net/10761/1643.

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Sheep meat is a source of polyunsaturated (PUFA) and monounsaturated (MUFA) fatty acids that confer beneficial effects to human health, but it also contains high concentration of saturated fatty acids (SFA) that are associated with the development of certain diseases. To attain a healthier intramuscular fatty acid composition, that is, meat with high PUFA to SFA ratio, and low in fatty acids n-6 to n-3 ratio, several strategies focused on animal feeding have been tested. However, a sufficient amount of antioxidants must be present in meat to counterbalance the increase in the content of readily oxidizable unsaturated fatty acids, which is vulnerable to oxidation, and from the associated deterioration of meat colour and proteins, thus antioxidants are crucial in preserving the nutritive value and extending the shelf life of the meat. The increasing costs of feedstuffs for livestock led to the utilization of cheaper resources as alternatives to reduce the production cost. Here, locally available materials and agro-industrial by-products commonly found in the Mediterranean countries (citrus pulp, carob pulp, and olive cake) were used in feeding trials with lambs and the effects on meat quality were evaluated. These plant-derived materials contain considerable amounts of secondary bioactive metabolites, which affect the fatty acid composition and/or act as antioxidants. Hence, it was hypothesized that at appropriate levels of inclusion in to the lamb diets, these feedstuffs would not negatively affect animal health and productivity, and would represent a strategy to naturally produce a healthy and oxidatively stable meat. In the first study (Experiment 1), Comisana male lambs were fed for 60 days:a conventional cereal-based concentrate diet, or concentrates in which 24% or 35% dried citrus pulp was included in partial replacement of barley. Following slaughter, the slices of longissimus thoracis et lomborum muscle were packed aerobically and stored for up to 6 days. The inclusion of citrus pulp in the diet effectively inhibited protein oxidation in meat by reducing protein radicals, carbonyl formation, and thiol loss in comparison to the Control. The results showed the ability of citrus pulp to be conveniently included among the ingredients of a concentrate-based diet and to result in an improved oxidative stability of meat proteins.In the second study (Experiment 2), Comisana lambs were fed for 60 days: conventional concentrates or a diet in which cereal concentrates were partially replaced by 24% or 35% carob pulp. The results demonstrated that feeding carob pulp did not affect animal productivity and improved the muscle content of PUFA, among which is rumenic acid, and reduced the SFA concentration and the n-6/n-3 PUFA ratio as compared to the control diet. Moreover, no extensive colour, lipid and protein oxidation in meat were observed over 6 days of aerobic storage. Therefore, dietary carob in lamb diet could be an effective strategy to improve the PUFA content in the meat without compromising animal growth performance and meat oxidative stability. In the third study (Experiment 3), the effect of feeding lambs with diets including linseed and olive cake on the evolution of volatile compounds (VOCs) in meat was assessed. Specifically, Appenninica lambs fed commercial concentrates or diets containing linseed, or olive cake, or combination of both. The VOC profile was determined through SPME-GC-MS analysis of raw and cooked meat The cooked meat showed higher concentrations of VOCs than raw meat and most of these were derived from fatty acid oxidation.Nevertheless, in both raw and cooked meat, none of the lipid oxidation-derived volatiles was significantly affected by the dietary treatments. Therefore, the results suggest that the replacement of cereal concentrates with linseed and/or olive cake in diets for lambs did not cause appreciable changes in VOC profile of meat.

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Nordi, Wiolene Montanari. « Efeito do fornecimento de colostro bovino liofilizado e caprino sobre o epitélio intestinal de caprinos recém-nascidos ». Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/11/11139/tde-14022011-084737/.

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Foi avaliado o fornecimento do colostro bovino liofilizado como alternativa de fonte inicial de imunoglobulinas para caprinos recém-nascidos bem como as características histológicas, considerando avaliações histomorfométricas, estereológicas, imunohistoquímicas e o número de células caliciformes no epitélio intestinal destes animais. Foram utilizados dois grupos de 15 cabritos, que receberam 5% do peso vivo de colostro bovino liofilizado (CBL) ou colostro caprino (CC), com 55 mg/mL de imunoglobulina G, às 0, 7 e 14 horas de vida. Amostras do duodeno, jejuno médio e íleo foram coletadas às 18, 36 e 96 horas de vida para análises histológica e imunohistoquímica. Três animais foram sacrificados logo após o nascimento, constituindo o grupo zero hora. O delineamento experimental foi inteiramente casualizado, sendo as variáveis morfométricas consideradas em arranjo fatorial 2x3+1, tendo como efeitos principais os dois tipos de colostro, os três horários de abate e o grupo zero hora. A concentração de IGF-I no colostro bovino liofilizado e colostro caprino foi de 158,71 e 356,32 ng/mL, respectivamente. A altura das vilosidades no jejuno mostrou-se superior (P<0,05), apresentando vilosidades 30,7% e 24,2% mais altas do que o duodeno e o íleo às 36h, respectivamente. O duodeno, às 18h, apresentou profundidade das criptas 48,4% maior que o jejuno e, às 96h as criptas duodenais mostraram-se 23,2% maiores que as criptas do íleo (P<0,05). No jejuno, as criptas apresentaram-se mais profundas às 96h (P<0,05) do que nos outros horários. A espessura da túnica muscular no jejuno apresentou-se mais espessa às 36 e 96h do que à zero h e mais espessa às 36h do que às 18h (P<0,05). No geral, jejuno e íleo, apresentaram túnica muscular menos espessa (P<0,05) que a encontrada no duodeno. Independente dos segmentos, às 96h a túnica muscular foi mais espessa que às 18h. O Vv da mucosa absortiva foi maior no jejuno, enquanto no íleo às 36h o Vv foi maior do que nos demais horários experimentais. Independente do segmento, às 36h o Vv foi 17,3% maior que às 96h. O número de células caliciformes no jejuno foi 78,6% menor às 18h (P<0,05) nos cabritos que ingeriram colostro caprino e 54,6% maior às 96h (P<0,05) nos animais que ingeriram colostro bovino liofilizado. Colostro bovino liofilizado pode ser utilizado como fonte de proteção passiva alternativa para os caprinos recémnascidos. O IGF-I presente no colostro não influenciou a morfometria entérica. O jejuno mostrou-se o segmento mais importante no processo absortivo de imunoglobulinas. A distribuição dos anticorpos internalizados pelo epitélio entérico mostrou-se relacionada aos segmentos do intestino e tempo de vida dos recém-nascidos, independente da fonte de anticorpos, bovina liofilizada ou caprina.
It was evaluated the supply of the lyophilized bovine colostrum as an alternative source of immunoglobulin for newborn goat kids and the histological characteristics, through histomorphometric, stereological, immunohistochemical evaluations and goblet cells number in the intestinal epithelium in this animals. Two groups of fifteen newborn goat kids received 5% of body weight of lyophilized bovine colostrum (LBC) or caprine colostrum (CC) with 55 mg/mL of immunoglobulin G at 0, 7 and 14 hr of life. Samples of duodenum, medium jejunum and ileum were collected at 18, 36 and 96 hr of life for histological and immunohistochemical analysis. Three animals were sampled just after birth representing the zero hr group. A completely randomized designing was used, and the variable morphometric was considered as 2x3+1 factorial arrangement, having as the main factors colostrum supply, the three slaughter hours and the zero hr group. The IGF-I concentration in lyophilized bovine colostrum or caprine colostrum was 158,71 and 356,32 ng/mL, respectively. Villous height was superior in the jejunum (P<0.05) with villous 30.7% and 24.2% higher than duodenum and ileum at 36hr, respectively. The duodenum showed at 18hr crypts 48.4% deeper than in the jejunum and at 96hr, the duodenal crypts was 23.2% deeper than ileum crypts (P<0.05). In the jejunum, crypts were deeper at 96hr compared to the other experimental hours. The muscularis submucosal thickness in the jejunum was thicker at 36 and 96hr than zero hr and was thicker at 36hr than 18hr. Jejunum and ileum, in general thinner (P<0.05) tunica muscular layer than found in the duodenum. Regardless of the segments, at 96hr, the muscularis submucosal was thicker than 18hr. The absorptive mucosa partial volume (Vv) was higher in the jejunum, while in the ileum the Vv was higher at 36hr than all other experimental dates. Regardless of the segments, at 36hr, the Vv was 17.3% higher than at 96hr. The goblet cells number was different in jejunum with 78.6% less cells at 18hr (P<0.05) in the goat kids fed caprine colostrum and 54.6% higher at 96hr (P<0.05) in the goat kids fed lyophilized colostrum. Lyophilized bovine colostrum can be used as an alternative source of passive protection for the newborn kids. The IGF-I present in colostrum didnt influence the enteric morphology. The jejunal epithelium was the most important segment related to absorption process. The internalized antibody distribution in the enteric epithelium showed related to the small intestine segments and post-partum period, regardless of the antibodies source, lyophilized bovine or caprine.

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Halbouche, Miloud. « Flux, digestion et utilisation des matières azotées par les caprins : contribution à la méthodologie d'estimation du flux digestif, influence de la réduction des apports alimentaires et de l'addition d'acides animés protégés ». Vandoeuvre-les-Nancy, INPL, 1994. http://docnum.univ-lorraine.fr/public/INPL_T_1994_HALBOUCHE_M.pdf.

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Nous avons étudié l'influence de la quantité et de la qualité des matières azotées alimentaires sur le flux des matières azotées dans les différents compartiments du tube digestif et sur l'utilisation de l'azote par les chèvres laitières. Trois séries d'essais ont été mises en place: limitation des quantités ingérées, modification des apports d'azote dégradable et supplémentation en acides aminés essentiels (lysine et méthionine). Les teneurs en marqueurs (PEG et Cr2 O3) du contenu duodénal varient au cours du nycthémère. Cependant la réduction du nombre de prélèvements d'échantillons (12 à 4) ne modifie pas significativement les valeurs estimées du flux duodénal. Un modèle déterministe des courbes d'isosaturation du rumen en marqueurs est proposé. Il permet le calcul du flux digestif duodénal à partir de paramètres cinétiques. La diminution des apports alimentaires s'est accompagnée d'une réduction de la dégradation et de la synthèse microbienne dans le rumen, ainsi que de l'absorption des matières azotées dans l'intestin grêle. La supplémentation de la ration en azote fermentescible et en acides aminés essentiels s'accompagne dans un premier temps d'une amélioration de l'utilisation métabolique de l'azote, puis cette efficacité marginale diminue pour des apports plus élevés

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Haq, Inam Ul. « Laboratory scale treatment of wheat straw with urea solution simulating treatment with urine at a tropical temperature : effects on in vitro digestibility to improve nutritive value for ruminant feeding ». Thesis, University of Reading, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298482.

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Nogueira, Ricardo Galbiatti Sandoval. « Enteric and feces methane emissions, fermentative ruminal parameters and feeding behavior of cattle fed cottonseed and vitamin E ». Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/10/10135/tde-02052017-125157/.

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Problems about greenhouse gas emissions attributed to cattle production and improvements in the productivity of these animals has been growing and becoming increasingly important. Cattle releases methane as part of their digestive process, and this represents loss of energy for the animal. The decomposition of feces releases methane and it can be recovered by digester and transformed into different types of energy. Thus, aiming to quantify the potential production of enteric methane and anaerobic fecal decomposition, as well as to evaluate ruminal and behavioral parameters of cattle fed with cottonseed and vitamin E. Six cannulated cows (864±16 kg) were distributed in a replicate 3x3 Latin square. Treatments were: 1) control diet; 2) CS: basal diet plus 30% cottonseed and 3) CSVitE: basal diet plus 30% of cottonseed plus 500 UI of vitamin E. Results were compared through orthogonal contrast and values were considered significant when P0,05. No differences were observed for dry matter intake (DMI), as well as digestibility of DM and neutral detergent fiber (NDF). Animals supplemented with cottonseed spent more time eating and ruminating and less time in idles. Reduction in the concentration and production of acetate, butyrate and the acetate: propionate ratio was observed in animals fed cottonseed compared to the control. Enteric methane mitigation was observed for the cottonseed treatments compared to the control. Changes in the substrates characteristics used to load the digesters were observed. However, no differences were verified for the total biogas production, methane yield and capacity to recover the energy of the feces in the form of methane. Inclusion of 30% cottonseed can be used as a strategy to mitigate enteric methane, without causing losses in the DMI, nutrients digestibility and anaerobic digestion of feces. In addition, it promoted favorable changes in the ingestive behavior, ruminal fermentation products, as well as in the energy partition of the gastrointestinal tract. Vitamin E when is used as antioxidant had not effect on ruminal fermentation, feeding behavior and feces anaerobic digestion, thus the inclusion is not advised due absence of positive results.
A problemática das emissões de gases de efeito estufa atribuída à produção de bovinos e melhorias na produtividade desses animais vem crescendo e se tornando cada vez mais importante. Bovinos emitem metano como parte do seu processo digestivo, e isto representa perda de energia para o animal. A decomposição das fezes gera metano, este pode ser recuperado por biodigestores e transformado em diferentes tipos de energia. Assim, objetivou-se quantificar o potencial de produção do metano entérico e da decomposição anaeróbia das fezes, bem como avaliar parâmetros ruminais e comportamentais de bovinos alimentados com caroço de algodão e vitamina E. Foram utilizadas seis vacas fistuladas não gestantes e não lactantes (876 kg±16). Os tratamentos foram: 1) Controle: dieta basal; 2) CA: dieta basal mais 30% de caroço de algodão; 3) CAVitE: dieta basal mais 30% de caroço de algodão mais 500 UI vitamina E. O delineamento experimental utilizado foi o quadrado latino. Os resultados foram comparados por contrastes ortogonais e foram considerados significantes valores de P0,05. Não foram verificadas diferenças para o consumo de matéria seca (MS), bem como digestibilidade da MS e da fibra em detergente neutro (FDN). Os animais suplementados com caroço de algodão passaram maior tempo comendo e ruminando e menor tempo em ócio. Houve redução na concentração e produção de acetato, butirato e da relação acetato:propionato dos animais que receberam caroço de algodão comparado ao controle. A inclusão do caroço de algodão provocou mitigação das emissões de metano entérico. Houve alteração nas características dos substratos utilizados para abastecer os biodigestores. No entanto, não foram verificadas diferenças para a produção total de biogás, rendimento de metano e capacidade dos biodigestores em recuperar a energia das fezes na forma de metano. A inclusão de 30% caroço de algodão pode ser utilizada como estratégia para mitigar metano entérico, sem causar perdas no consumo, digestibilidade dos alimentos e na biodigestão anaeróbia das fezes. Além disso, sua inclusão promoveu alterações favoráveis no comportamento ingestivo, nos produtos da fermentação ruminal, bem como na partição de energia do trato gastrointestinal. A vitamina E quando utilizada como antioxidante não possui efeitos sobre a fermentação ruminal, comportamento ingestivo e biodigestão anaeróbia das fezes, assim sua inclusão não é indicada devido a ausência de resultados favoráveis a sua utilização.

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Silva, Tâmara Lúcia dos Santos [UNESP]. « Qualidade da carne de cordeiros alimentados com levedura seca inativa (saccharomyces cerevisiae) da cana-de-açúcar em substituição ao farelo de soja ». Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/105098.

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Made available in DSpace on 2014-06-11T19:33:36Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-12-17Bitstream added on 2014-06-13T21:06:39Z : No. of bitstreams: 1 silva_tls_dr_botfmvz.pdf: 469730 bytes, checksum: fef540eada210b35cbd086f20dc1bed2 (MD5)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Universidade Estadual Paulista (UNESP)
O objetivo do presente estudo foi avaliar a qualidade da carne de cordeiros mestiços Santa Inês alimentados com levedura (Saccharomyces cerevisiae) inativa da cana-de-açúcar em substituição ao farelo de soja. Foram ofertadas dietas com quatro níveis de substituição (0, 33, 66 e 100%) de levedura aos animais que foram abatidos com 35 kg de peso vivo. Foram realizadas as análises físicas e a determinação de umidade, proteínas, cinzas, gordura e colesterol no músculo Longissimus dorsi. Os níveis de substituição de 33 e 100% influenciaram a composição protéica da carne e os valores de lipídio não apresentaram diferença entre os tratamentos (P>0,05). O teor de colesterol foi menor para os animais que receberam dietas contendo levedura. O índice de fragmentação miofibrilar apresentou diferença entre os níveis de substituição. A maciez, quando analisado pelo método físico, foi satisfatória em carnes do tratamento 33% de substituição
This study aimed to evaluate Santa Inês lambs meat wich was fed with inactive yeast (Saccharomyces cerevisiae) instead of soy meal. The treatments offer were four levels (0, 33, 66 e 100%) of yeast to animals until the weight average 35 kg and they were slaughtered. The analyses were physical and humidity determination, protein, ash, fat cholesterol and in Longissimus dorsi muscle. The inclusion levels influenced in the protein composition of meat. The lipid values were similar (p> 0,05) between the treatments. The values of the tenderness fragmentation index showed variation between treatments. When the softness was analyzed by a physical method it confirmed that the meat has a satisfactory level of tenderness and cholesterol is similar to animals fed with yeast

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Silva, Tâmara Lúcia dos Santos 1984. « Qualidade da carne de cordeiros alimentados com levedura seca inativa (saccharomyces cerevisiae) da cana-de-açúcar em substituição ao farelo de soja / ». Botucatu : [s.n.], 2012. http://hdl.handle.net/11449/105098.

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Orientador: André Mendes Jorge
Coorientador: José Teodorico de Araújo Filho
Banca: Cledson Augusto Garcia
Banca: Paulo Roberto Meirelles
Banca: Cristiana Andrighetto
Banca: Janaina Haddich Conte
Resumo: O objetivo do presente estudo foi avaliar a qualidade da carne de cordeiros mestiços Santa Inês alimentados com levedura (Saccharomyces cerevisiae) inativa da cana-de-açúcar em substituição ao farelo de soja. Foram ofertadas dietas com quatro níveis de substituição (0, 33, 66 e 100%) de levedura aos animais que foram abatidos com 35 kg de peso vivo. Foram realizadas as análises físicas e a determinação de umidade, proteínas, cinzas, gordura e colesterol no músculo Longissimus dorsi. Os níveis de substituição de 33 e 100% influenciaram a composição protéica da carne e os valores de lipídio não apresentaram diferença entre os tratamentos (P>0,05). O teor de colesterol foi menor para os animais que receberam dietas contendo levedura. O índice de fragmentação miofibrilar apresentou diferença entre os níveis de substituição. A maciez, quando analisado pelo método físico, foi satisfatória em carnes do tratamento 33% de substituição
Abstract : This study aimed to evaluate Santa Inês lambs meat wich was fed with inactive yeast (Saccharomyces cerevisiae) instead of soy meal. The treatments offer were four levels (0, 33, 66 e 100%) of yeast to animals until the weight average 35 kg and they were slaughtered. The analyses were physical and humidity determination, protein, ash, fat cholesterol and in Longissimus dorsi muscle. The inclusion levels influenced in the protein composition of meat. The lipid values were similar (p> 0,05) between the treatments. The values of the tenderness fragmentation index showed variation between treatments. When the softness was analyzed by a physical method it confirmed that the meat has a satisfactory level of tenderness and cholesterol is similar to animals fed with yeast
Doutor

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McEleney, E. « Individual feed intake by ruminants in group feeding situations ». Thesis, University of Glasgow, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374546.

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Mack, Claudia Isabell. « The effect of fine particle removal from ground forage samples on In Saccro dry matter and neutral detergent fiber disappearance values ». Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/6609.

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Thesis (MScAgric (Animal Sciences))--University of Stellenbosch, 2011.
ENGLISH ABSTRACT: In vitro and in situ methods using the in sacco technique have a wide application in ruminant nutrition as they allow the degradability and quality of forages and ruminant diets to be determined quicker and at a lower cost than in vivo methods. These trials make use of artificial fibre bags, made of polyester (dacron) or nylon which are available in variable pore sizes. Results from such degradability trials are of great value to feed formulation programs such as AMTS.cattle and CPM Dairy and the more accurate the results are obtained from such trials the more accurate feed formulation models are enabling the ruminant nutritionist to formulate the best diet possible to reach the genetic potential of ruminants. The accepted method for in sacco trials (NRC, 2001) requires that the feed samples are ground through a 2 mm screen. This usually results in a variety of particle sizes, including a significant amount of extremely fine particles. Research has, however, shown that these fine particles can potentially be washed out of the dacron bags that are used in in sacco degradability trials. This would result in an overestimation of the soluble and rapidly fermentable nutrient fractions. The objective of this study was to determine the effect of fine particle removal from ground forage samples on the chemical composition and in vitro dry matter (DM) and neutral detergent fibre (NDF) degradability of forages. Lucerne hay, oat hay and wheat straw samples were sourced from seven different locations in the Western Cape. Samples were milled through a 2 mm screen and then sieved through either 150 μm, 125 μm or 106 μm. All fractions were analysed for DM, crude protein (CP), NDF, fat and ash. Based on the NDF content of the original samples, four samples from each forage type were selected for in vitro trials to determine DM and NDF disappearance over time. Samples were incubated for 0, 6, 24 and 48 hours in an ANKOM Daisy II incubator. Significant variation occurred within forage types in terms of chemical composition. Fine particle removal had no effect on the NDF content of lucerne hay and wheat straw, but sieved oat hay fractions had a higher NDF content than the un-sieved samples. The NDF content was on average 635.9 for the sieved OH fractions, whereas the NDF content of the un-sieved samples was 606.8. The CP content of sieved oat hay (61.4 on average) and wheat straw fractions (47.7 on average) were lower than the un-sieved fractions (65.7 for OH and 55.4 for WS), whereas for lucerne hay, sieving had no effect on CP content. Dry matter and NDF disappearances were significantly higher for the un-sieved samples than for the sieved fractions for all three forage types at all incubation times, which indicates an overestimation of the soluble and readily digestible forage fractions. Compared to sieved samples, DMD values at 0 hours (washing only) of the un-sieved samples were, on average, 13.8% higher for lucerne hay, 27.3% for oat hay and 44.7% for wheat straw. At 48 h, the overestimation of lucerne DMD for the un-sieved samples was between 4.0% (compared to 106 μm sieve) and 7.3% (compared to 150 μm sieve). This over-estimation in the un-sieved samples was carried over to all four time points. No significant differences between the fractions (150, 125 and 106) were found within a forage type at all incubation times. The estimated degradation rates and the predicted digested proportions were also significantly higher for the un-sieved fractions compared to the sieved fractions. It was concluded that fine particle removal from forage samples would result in more accurate estimations of in sacco nutrient degradability.
AFRIKAANSE OPSOMMING: In sacco in vitro- en in situ-metodes word dikwels toegepas in die studie van herkouervoeding aangesien hierdie metodes vinniger, meer effektief en meer ekonomies is as in vivo-metodes. Hierdie studies maak gebruik van kunsveselsakkies, gemaak van poliëster (dacron) of nylon wat beskikbaar is in verskeie poriegroottes. Resultate van sulke verteringsproewe is belangrik vir toepassing in voerformuleringsprogramme soos AMTS.cattle en CPM Dairy. Die resultate wat deur hierdie studies verkry word, is belangrik vir akkurate voerformulering deur formuleringsmodelle en stel die herkouervoedingkundige in staat om die ideale voer te formuleer vir die manifestering van die dier se genetiese potensieaal. Die aanvaarde in sacco-metode (NRC, 2001) vereis dat voermonsters deur ‘n 2 mm sif gemaal word wat ‘n groot verskeidenheid partikelgroottes tot gevolg het met ‘n beduidende hoeveelheid baie fyn materiaal. Navorsing het getoon dat hierdie baie fyn partikels uit die dacronsakkies gewas kan word tydens in sacco verteringstudies, met die gevolg dat die oplosbare en vinnig-verteerbare fraksie oorskat kan word. Die doel van die huidige studie was om die invloed van die verwydering van fyn partikels op die chemiese samestelling van ruvoermonsters te bepaal, asook die in vitro droë materiaal (DM) en neutraal-onoplosbaare vesel (NDF) verteerbaarheid daarvan. Monsters van lusernhooi, hawerhooi en koringstrooi, afkomstig van sewe verskillende lokaliteite in die Wes-Kaap, is deur 'n 2 mm sif gemaal en sub-monsters is deur ‘n reeks siwwe met poriegroottes van 150 μm, 125 μm of 106 μm gesif. Al die fraksies is geanaliseer vir DM, ruproteïen (RP), NDF, vet en as. Vier monsters van elke voertipe is op grond van die NDF-inhoud geselekteer vir in vitro-studies om die DM- en NDF- verteerbaarheid oor tyd te bepaal. Monsters is vir 0, 6, 24 of 48 uur geïnkubeer. Die resultate het getoon dat daar betekenisvolle variasie in chemiese samestelling binne ruvoertipes voorgekom het. Die verwydering van die fyn partikels het geen invloed die NDF-inhoud van lusernhooi en koringstrooi gehad nie. Wat hawerhooi betref, was die NDFinhoud van die gesifte monsters egter betekenisvol hoër in vergelyking met die ongesifte monsters. Die NDF inhoud was gemiddeld 635.9 vir die gesifte monsters en vir die ongesifte monsters 606.8. Sifting het geen invloed op die RP-inhoud van lusernhooi gehad nie, maar vir hawerhooi (61.4 gemiddeld) en koringstrooi (47.7 gemiddeld) was die RP-inhoud van die gesifte monsters betekenisvol laer as dié van die ongesifte monsters (65.7 vir hawerhooi en 55.4 vir koringstrooi). In vergelyking met die gesifte monsters, was die in vitro DM- en NDF-verteerbaarhede betekenisvol hoër vir die ongesifte monsters vir al drie ruvoertipes by alle inkubasietye. Hierdie resultate bevestig ‘n oorskatting van oplosbare en maklik verteerbare fraksies in gemaalde voermonsters. In vergelyking met die gesifte monsters, was die DMV-waardes van die ongesifte monsters by 0 ure (slegs gewas) gemiddeld 13.8% hoër vir lusernhooi, 27.3% vir hawerhooi en 44.7% vir koringstrooi. Na 48 h inkubasie was die oorskatting van lusern DMV vir die ongesifte monsters tussen 4.0% (vergeleke met die 106 μm sif) en 7.3% (vergeleke met 150 μm sif). Die oorskatting is oorgedra na al vier inkubasietye. Die resultate het geen noemenswaardige verskille tussen die fraksies (150 μm, 125 μm en 106 μm poriegroottes) van ‘n ruvoertipe by enige inkubasietyd aangedui nie. Die beraamde verteringstempo’s en verteerde fraksies was ook aansienlik hoër vir die ongesifte monsters in vergelyking met die gesifte monsters. Die gevolgtrekking is gemaak dat die verwydering van fyn partikels uit gemaalde ruvoermonsters die akkurate bepaling van in sacco verteerbaarheidswaardes verhoog.

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Llorente, Eduardo Gallo. « Ammonia and urea treatment of wheat straw for feeding to ruminants ». Thesis, Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/91048.

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The effect of treatment with 3% aqueous ammonia and 5.3% urea plus jackbean meal on the nutritive value of wheat straw was investigated. The moisture content of the straw was raised to 40% by addition of water. Crude protein and in vitro dry matter digestibility were highest for the bottom layers, which had the highest moisture. The mean temperature during the first 4 wk post treatment was 11.2 C. Four diets were fed to sheep: untreated straw 1) alone or 2) with 20 g/d urea at feeding time 3) ammonia-treated straw, and 4) urea-treated straw. All diets contained 80 g of liquid molasses, 10 g of NaCl and 6 g of Na 2 S04, and were calculated to be isonitrogenous except the control diet (untreated straw without urea supplementation). Straw was chopped prior to feeding. Crude protein content in wheat straw was tripled by ammonia and urea treatment. Dry matter digestibility in vivo and in vitro was enhanced by ammonia and urea treatment, and the effect was higher for ammonia treatment. Digestibilities of cell wall constituents were higher (P<.05) for ammonia treated straw, compared to urea-treated straw. Urinary N excretion was considerably lower (P<.01) and N retention was higher (P<.01) for lambs fed treated straws, compared to those fed urea at feeding time. Ruminal NH3-N and blood urea concentrations were higher (P<.01) for the lambs fed urea at feeding time, compared to lambs fed the others diets.
M.S.

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Mohamed, Neijat. « Assessing the feeding value of pea straw and evaluating biological methods to improve its utilisation by ruminants ». Title page, contents and abstract only, 1995. http://web4.library.adelaide.edu.au/theses/09AS/09asm697.pdf.

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Copies of the author's previously published articles inserted. Bibliography: leaves 142-159. Provides information on the significance of pea straw as a ruminant feed and the potential of two biological techniques for improving its feeding value.

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Thiago, L. R. L. de S. « Voluntary intake of forages by ruminants : Factors relating to eating behaviour and rumen fill ». Thesis, University of Reading, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380847.

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Ilse, Breanne Rose. « Effects of Linseed Meal on Growth and Reproductive Performance in Ruminants ». Thesis, North Dakota State University, 2011. https://hdl.handle.net/10365/28744.

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Linseed meal (LSM) was fed to ovariectomized ewes exposed to estradiol 17-? (E2) implants over time, and LSM was supplemented to beef cows during late gestation and early lactation to evaluate the estrogenic potential of the phytoestrogen secoisolariciresinol diglycoside (SDG) found in LSM. Forty-eight ovariectomized ewes were fed a diet containing 12.5% LSM for 0, 1, 7, or 14 d and implanted with estradiol-17? (E2) for 0, 6, or 24 h before tissue collection. Uterine cellular proliferation, vascularity, and the expression of the angiogenic factors and their receptors were recorded. There was an interaction of LSM and E2 on uterine mass (P = 0.05). At 24 h of E2 exposure, proliferation was reduced (P < 0.001) when ewes were fed for 14 d compared to being fed 0 or 1 days. There was a LSM x E2 interaction (P ? 0.03) on VEGF receptor-2 (KDR) and hasicfihrohlast growth factor receptor (FGFR2) decreasing by 24 h E2 exposure. Exposure of LSM and E2 may impact the estrogenic response of sensitive tissue. Two studies were conducted to examine the effects of supplementing beef cows with LSM during late gestation or early lactation on calf growth and development. In Experiment 1, multiparous cows received either LSM or a control (CON) supplement (approximately 10% diet dry matter) for the last 60 d of gestation. Offspring weights, ADG, heifer age at puberty, conception percentage and steer carcass characteristics were recorded. In Experiment 2, multiparous cows received LSM or CON supplements (approximately 10% diet dry matter) during the first 60 d of lactation, and only heifer calf development performance was observed and recorded. Heifer calf weight, average daily gain, and attainment of puberty were assessed. For both experiments, birth weight, weaning weight and ADG were not affected (P > 0.31) by LSM supplementation. While final body weights were heavier (P = 0.04) for steer calves in Experiment 1, there was no effect (P = 0.09) of supplementation on carcass characteristics. In Experiment 1 and 2, attainment of puberty in heifer calves was not influenced (P > 0.58) by supplement type. Linseed meal supplementation during late gestation or early lactation does not appear to have a negative impact on calf growth, onset of puberty in heifer calves, or steer carcass quality, implicating that it may make a good supplement choice in cattle.

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Yulistiani, Dwi. « The nutritive value of rice straw varieties for ruminants ». Title page, Contents and Abstract only, 1997. http://web4.library.adelaide.edu.au/theses/09AS/09asy95.pdf.

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Bibliography: leaves 102-114. This study evaluates the difference in the nutritive value of rice straw varieties using chemical composition and digestibility measurements. It assesses several methods for improving the nutritive value of rice straw and the effect of urea treatment and rice straw quality on the colonisation of ruminal fungi and the characteristics of stem tissue structure.

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URIAS, ALEJANDRO RUBEN. « EFFECT OF DIETARY CONCENTRATE LEVELS ON IN SITU DRY MATTER DISAPPEARANCE, NEUTRAL DETERGENT FIBER DISAPPEARANCE AND DIGESTION KINETICS OF ALFALFA HAY, WHEAT STRAW AND STEAM PROCESSED AND FLAKED MILO GRAIN ». Diss., The University of Arizona, 1986. http://hdl.handle.net/10150/183830.

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A replicated 3 x 3 latin square design (3 periods and 6 rumen fistulated steers) was utilized to investigate the effect of dietary concentrate levels (30, 60 and 90%) on the in situ disappearance of dry matter (ISDMD) and neutral detergent fiber (NDF) and kinetics of fiber digestion of alfalfa hay, wheat straw and steam processed and flaked milo (SPFM). Concentrate levels of 30 and 60% did not affect (P > .05) ISDMD or NDF disappearance from any of the substrates. However, ISDMD and NDF disappearance of all substrates were depressed (P < .05) by the 90% concentrate diet. The degradation of the potentially digestible fiber in these substrates followed first order kinetics at all concentrate levels. Fiber digestion kinetics were not affected (P > .05) by dietary concentrate levels of 30 or 60%. Incubation of substrates in animals receiving the 90% concentrate diet resulted in lower potential extent of digestion (P > .05) and decreased rate of degradation (P > .05) for all substrates. However, digestion was not complete even after incubations of 168-h, and thus, it is possible that the potential extent of digestion was underestimated. For all substrates lag time of digestion appeared to increase in the 90% concentrate diet. However, influx of NDF-like material into the bag during incubation makes the validity of the lag times obtained in situ questionable. Ruminal pH was depressed in animals consuming the 90% concentrate diet and could be at least one of the factors responsible for the decreased (P > .05) fiber digestibility in this diet. Mean ruminal pH of 6.5 (30 and 60% concentrate diets) did not depress (P > .05) fiber digestibility while a mean pH of 6.2 resulted in a lower (P > .05) fiber digestibility in the rumen.

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Mukisira, Ephraim Amiani. « The influence of alkaloids on voluntary intake and performance by ruminants fed diets containing lupin seed in Kenya ». Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=41730.

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Lupin seed has the potential to be used as a protein supplement in ruminant rations, but its usage is restricted by the presence of alkaloids. Experiments were conducted with the aim of determining whether the removal of specific toxic alkaloids, lupanine and 13-hydroxylupanine, from crushed lupin seed (CLS) would improve the organic matter intake (OMI) and average daily gains (ADG) in lambs, and also improve the lactation performance in dairy cows. Effects on liver function in lambs were also investigated. An additional study on the effects of the detoxification of CLS on the degradation of protein was conducted. In Experiment 1, 30 growing Corriedale lambs were fed five diets for 105 d according to a randomized complete block design (RCBD) with six blocks. Two diets contained intact CLS at 15% (LUI-15) or 30% (LUI-30) of DM; two other diets contained detoxified CLS at 15% (LUD-15) or 30% (LUD-30) and the control (CON) diet was supplemented with crushed sunflower seed, which was locally prepared, on-farm. All diets were formulated to be isonitrogenous (16% CP). The alkaloid content (lupanine and 13-OH lupanine) of the diets was.31,.70,.21 and.52% for LUI-15, LUI-30, LUD-15 and LUD-30, respectively. Thus, diets containing detoxified CLS contained approximately 30% less alkaloids than those with intact CLS. Estimates of ADG of lambs fed diets containing detoxified CLS was higher (P $<$.01) (120 g.d$ sp{-1}$) than that of lambs fed intact CLS (76 g.d$ sp{-1}$). The OMI (73 g/Wkg$ sp{0.75}$) was also higher, although not significantly, for lambs fed diets containing detoxified CLS. Feed conversion efficiency was increased (P $<$.05) by the detoxification of CLS. Lambs fed diets containing intact CLS consumed more OMI as time progressed, suggesting that adaptation to CLS might have occurred. Lambs fed diets containing intact CLS demonstrated increased trends in the activity in plasma of the enzymes glutamic oxaloacetic transferase (GOT) and $ gamma$-glutamyl transfer

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26

Elliott, Stephen David. « The effects of monoterpenes on feeding and digestion in ruminants using an in vitro technique ». Thesis, University of Edinburgh, 1985. http://hdl.handle.net/1842/13791.

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Murphy, Timothy Alan. « The effects of restricted feeding on diet digestibility, performance and carcass composition of growing ruminants / ». The Ohio State University, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487848531362798.

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Pagella, Jose Horacio. « Urinary benzylated compounds as potential markers of forage intake and metabolism of their precursors in ruminants ». Thesis, University of Aberdeen, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369561.

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The quantitative relationship between the urinary excretion of TBA and the uptake of PPA and CHCA was examined by continuous intraruminal infusion of PPA (8, 16 or 24 mmol/d) either alone or with CHCA (8 or 16 mmol/d) in sheep nourished by intragastric infusions of all nutrients. The daily excretion of TBA was linearly correlated (r 0.99, P<0.001) with the amounts of PPA and CHCA infused. The urinary recovery of infused PPA and CHCA as TBA was 0.79 (s.e. 0.01). Recovery of infused SA (8 mmol/d) as urinary total salicylic acid (TSA) was 0.89 (SD 0.08). Both TBA and TSA excretions were found to be exclusively of exogenous origin, with negligible faecal excretion. It is concluded that urinary TBA is a potential estimator of PPA + CHCA absorption from the digestive tract. SA may have potential as a marker of urine volume. The relationship between urinary excretion of TBA and forage intake was assessed with steers fed different amounts of fresh herbage from pastures comprising oat, rye, vetch and lucerne. Herbage samples collected daily were incubated in vitro with buffered rumen fluid for 48 h. The PPA production per unit of herbage DM incubated was fitted to the exponential function of time Y = a + [b. (1 - e^-c.l)]. Regression analysis showed that the TBA:creatine concentration ratio was a good explanatory variable (r²0.92-095; P<0.001) of herbage intake. TBA:creatinine concentration ratio divided by the product b.c, both constants from the fitted curves of PPA production of herbage cultures, was another good index (r² up to 0.98). It is concluded that a method for the prediction of herbage intake for grazing animals based on TBA excretion in urine seems promising.

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Bianchini, Waldmaryan [UNESP]. « Isótopos estáveis do carbono como indicativo da fase lactente-ruminante em bubalinos Murrah ». Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/95268.

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Made available in DSpace on 2014-06-11T19:27:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-07-28Bitstream added on 2014-06-13T20:56:40Z : No. of bitstreams: 1 bianchini_w_dr_botfmvz.pdf: 625794 bytes, checksum: 39e58158fd9b6061d06d312f793e4743 (MD5)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Universidade Estadual Paulista (UNESP)
Este estudo buscou determinar através da utilização dos isótopos estáveis do carbono a fase em que o bezerro já está apto para ser desmamado e capaz de consumir alimentos sólidos. Para isso foram coletadas ao longo do período experimental amostras de fezes e sangue, para monitorar o comportamento do turnover do carbono em quatro bezerros bubalinos que recebiam dieta C3 em cocho privativo durante amamentação e leite proveniente de búfalas que se alimentavam de pasto C4. As análises isotópicas foram realizadas no Centro de Isótopos Estáveis do Instituto de Biociências da UNESP, campus de Botucatu. Para mensurar o turnover do carbono nos tecidos em determinado intervalo de tempo, foi utilizado o método sigmoidal de regressão de Boltzmann ou a função exponencial do tempo. Os resultados isotópicos das amostras dos animais que foram submetidos à análise por meio do modelo de Boltzmann ou equação exponencial evidenciaram a dinâmica de consumo do grupo durante os primeiros dias de vida. A meia-vida nas fezes do animal 1091 foi de 224,8 dias e no animal 1093 foi de apenas 61,2 dias, no sangue apenas no animal 1093 foi possível determinar a meia-vida, que foi de 125,6 dias e no plasma sangüíneo a meiavida do animal 1091 foi de 63,8 dias, no animal 1093 foi de 88 dias e no animal 1094 foi de 53,3 dias. Portanto, pode-se concluir que fezes não podem ser consideradas marcadores de digesta confiáveis para as condições deste estudo, apenas como indicadores de consumo. Plasma e sangue total foram eficientes em determinar o tempo de desmame para bubalinos Murrah.
This study it searched to determine through the use of stable isotopes of carbon the phase where the year-old calf already is apt to be weaned and capable to consume solid foods. For this samples of blood and faeces had been collected throughout the experimental period, to monitor the behavior of turnover of carbon in four buffaloes year-old calves that received privative C3 diet during breast-feeding and milk proceeding from buffalos that if they fed of C4 grass. The isotopic analyses had been carried through in the Steady Isotope Center of the Institute of Biociências of the UNESP, campus of Botucatu. To measure turnover of carbon in fabrics in determined time interval, the sigmoid method of regression of Boltzmann or the exponential function of the time was used. The isotopic results of the samples of the animals that had been submitted to the analysis by means of the model of Boltzmann or exponential equation had evidenced the dynamics of consumption of the group during the first days of life. The stocking-life in faeces of animal 1091 was of 224,8 days and in animal 1093 it was of only 61,2 days, in the blood only in animal 1093 was possible to determine the stocking-life, that was of 125,6 days and in the plasma sanguine the stocking-life of animal 1091 was of 63,8 days, in animal 1093 it was of 88 days and in animal 1094 it was of 53,3 days. Therefore, it can be concluded that faeces cannot be considered true markers of digestibility for the conditions of this study, as only indicating of consumption... (Complete abstract click electronic access below)

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DELFINO, FRANCIS JOSEPH. « IDENTIFICATION AND CHARACTERIZATION OF CEREAL GRAIN TISSUES RESISTANT TO RUMEN MICROBIAL DIGESTION USING IN SITU, IN VITRO AND SCANNING ELECTRON MICROSCOPY TECHNIQUES ». Diss., The University of Arizona, 1986. http://hdl.handle.net/10150/183909.

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A series of studies was conducted using SEM in conjunction with chemical analysis, in situ and in vitro digestion techniques, to characterize the anatomical components from barley, corn, sorghum and wheat grains which constitute "fiber" and investigate their susceptibility to rumen microbial digestion. Fractured grains were used to identify anatomical features and cell types prior to and after extraction or digestion. Certain anatomical features, including pericarp tissue, aleurone cells, endosperm cell walls, corneous and floury endosperm tissue and lemma and palea from barley, were easily identifiable in fractured and ground grains, and in neutral detergent extracted or digested residues. In situ and in vitro incubation conditions were varied to assess the effect of concentrate and/or reduction of pH on the disappearance of identifiable grain fractions. In situ incubations were conducted using steers adapted to 0-, 30- and 90% concentrate diets. In vitro inoculum buffered at pH 7 or 6 was provided by a steer fed 0- or 90% concentrate. Tissues resistant to rumen microbial digestion during extended (144-h) in situ incubations and shorter term (12- to 48-h) in vitro incubations were primarily those identified in NDF, and included pericarp, lemma and palea, and small amounts of corneous endosperm. Remaining tissues identified included barley lemma, palea and pericarp; corn pericarp, tip cap and small amounts of corneous endosperm; sorghum pericarp and corneous endosperm with matrix and protein bodies; and wheat pericarp. In vitro disappearance of isolated NDF after 48-h ranged from 43% for barley to 89% for corn. Labile structures included embryonic tissue and portions of endosperm cell walls, protein matrix and residual starch. Resistant tissues included pericarp, aleurone cell walls, tip cap and portions of the corneous endosperm. Relative rankings of NDF digestibility under all conditions studied were similar (corn > sorghum > wheat > barley) whether determined using isolated NDF or calculated from TIVDMD residues. Neither concentrate level fed to the host animal nor pH of the in vitro incubation flask affected rankings among grains, although increasing concentrate level and/or reducing pH appeared to reduce in vitro NDF disappearance. Evaluation of electron micrographs of fractured grains suggested that similar anatomical structures in the various grains differed in their resistance to microbial digestion. For example, pericarp from barley and wheat appeared to be more resistant than that from corn or sorghum. Endosperm of barley was less resistant than that of sorghum.

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31

Goosen, Liezel. « The effect of an exogenous fibrolytic enzyme on forage digestibility parameters ». Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/50141.

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Thesis (MScAgric) -- Stellenbosch University, 2004.
ENGLISH ABSTRACT: The ruminant has the ability to utilize forages more efficiently than any other production animal. The utilization of forage fibre is an important aspect of ruminant production systems, as this is the main source of energy available to the animal. The availability of high-fibre forage nutrients is, however, restricted by cell wall degradability, and since low quality forages contribute a great deal to ruminant production systems worldwide, the improvement of this degradation process is of major economic importance. The use of exogenous fibre degrading enzymes has been proposed as a means of enhancing this process, with positive results being obtained from in vitro studies incorporating exogenous enzyme preparations. Positive in vivo results with regard to forage digestibility and other animal production parameters have consequently also been obtained following the addition of exogenous fibre-degrading enzyme preparations to the ruminant diet. Two initial screening experiments were undertaken in order to identify fungal enzyme preparations that may have a positive effect on in vitro fibre degradability. The initial screening employed an in vitro organic matter digestibility technique, and was successful in identifying at least six enzyme preparations displaying enhanced digestibility results that were statistically significant. A second in vitro gas production procedure was used to confirm results obtained from organic matter digestibility assays, as well as to increase screening capacity in order to evaluate new enzyme preparations more time-efficiently. Statistical analysis of results obtained from the secondary screening identified various enzyme candidates producing promising results. Only one of these, Abo 374, proved to be statistically superior to the control and other enzyme preparations. A growth trial was subsequently conducted to assess the performance of this enzyme in vivo. The trial involved individual feeding of 32 Dohne Merino ram lambs grouped according to weights into four groups consisting of 8 lambs each. Each group represented a specific application level of enzyme to the wheat straw component of a high fibre diet, amounting to 10, 5, or 1 ml enzyme supematant/kg straw. The enzyme was diluted with water at appropriate rates to obtain an application rate of 300ml/kg straw. The fourth (control) group was treated with water at the same application rate. The trial was conducted over a period of six weeks, during which feed intakes, weekly weight gains, as well as feed conversion efficiencies were recorded. Results suggested significant weight gains in the high (10ml/kg) and medium (5ml/kg) treatment groups, indicated by a P-value of 0.04. Similarly, feed conversion efficiencies were improved for above-mentioned groups (P=0.05), while feed intakes did not differ significantly between the four experimental groups.
AFRIKAANSE OPSOMMING: Die herkouer besit die vermoee om ruvoere beter as enige ander produksiedier te kan benut. Die gebruik van ruvoervesel is 'n belangrike aspek van herkouer produksiesisteme, aangesien ruvoere die hoof bron van energie aan die herkouer verskaf. Die beskikbaarheid van hoe-vesel ruvoer nutriente word egter beperk deur die degradeerbaarheid van die selwand, en aangesien lae kwaliteit ruvoere 'n groot bydrae tot wereldwye herkouer-produksiesisteme maak, is die moontlike verbetering van hierdie degraderingsproses van groot ekonomiese belang. In 'n poging om hierdie verteringsproses te help bevoordeel, is die gebruik van eksogene veselverterende ensieme ondersoek, en positiewe resultate is verkry wanneer hierdie ensieme in in vitro studies gebruik is. Goeie verbeterings ten opsigte van ruvoer verteerbaarheid en ander diereproduksie parameters is ook verkry deur middel van in vivo studies waar eksogene ensieme by die ruvoer van herkouers gevoeg IS. Twee eksperimente is ondemeem in 'n poging om ensiempreparate wat 'n moontlike positiewe effek op in vitro veselvertering mag he, te identifiseer. Die eerste, 'n in vitro organiese materiaal verteerbaarheid tegniek, was suksesvol in die identifisering van minstens ses ensiem preparate wat statisties betekenisvolle verbeterings ten opsigte van verteringsresultate geproduseer het. 'n Tweede in vitro gasproduksie prosedure is vervolgens gebruik om resultate verkry vanaf die eerste tegniek, te bevestig, asook om evalueringskapasiteit te vergroot en sodoende, nuwe ensiempreparate meer tydseffektief te evalueer. Statistiese evaluering van resultate verkry uit die tweede in vitro tegniek het 'n reeks ensieme met positiewe resultate opgelewer. Een van hierdie, Ab0374, het statisties betekenisvolle resultate ten opsigte van die kontrole, sowel as ander ensieme getoon. In 'n volgende eksperiment is 'n groeiproef gedoen om die effektiwiteit van hierdie ensiem in vivo te toets. In die proef is 32 Dohne Merino ramlammers op grond van hul gewig in vier groepe van agt skape elk verdeel, en individueel gevoer. Die groepe het verskillende toedieningsvlakke van die toetsensiem, toegedien tot die koringstrooi komponent van 'n hoe-vesel dieet, ontvang. Toedieningsvlakke was 10, 5, of lml ensiemkonsentraat/kg strooi. Elke groep se ensiemkonsentraat is verdun met die toepaslike hoeveelheid water om 'n toedieningsvlak van 300ml ensiemoplossing/kg koringstrooi te verkry. 'n Vierde groep is behandel slegs met water teen dieselfde toedieningsvlak, en het gedien as 'n kontrole. Die eksperiment is oor 'n periode van 6 weke uitgevoer. Tydens die proeftydperk is voerinnames, weeklikse gewigstoenames, sowel as voeromsetverhoudings, gedokumenteer. Resultate het betekenisvolle gewigstoenames in die hoe (lOml/kg) en medium (5ml/kg) groepe opgelewer, aangedui deur 'n P-waarde van 0.04. Voeromsetverhoudinge het ook verbeteringe getoon vir bogenoemde twee groepe (P=0.05), terwyl voerinnames nie merkbaar tussen die vier groepe verskil het nie.

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Norvell, Tess Marie. « Effects of increasing tetany risk ratio and magnesium supplementation on mineral balance and feeding behavior by ruminants ». Thesis, Montana State University, 2011. http://etd.lib.montana.edu/etd/2011/norvell/NorvellT0511.pdf.

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Three experiments were conducted to evaluate the effects of increasing the tetany risk ratio on blood serum Mg levels, nutrient digestion, mineral balance, and Mg supplementation source and feeding behavior. Experiments 1 and 2 were randomized complete block designs, with 24 wethers were maintained in individual metabolism crates and assigned to four treatments (6 wethers/treatment). Experiment 1 compared tetany risk ratios (TRR) of 1.6, 2.3, 2.9, or 3.5. Dry matter, NDF, and N digestibilities were not different between treatments. Nitrogen retention decreased (P < 0.05) as the tetany risk ratio increased. No treatment differences were recorded in Mg, Ca, K, or P balance. The TRR 2.3 treatment had the greatest decrease (P < 0.05) in serum Mg after 15d. Experiment 2 compared tetany risk ratios of 1.5, 2.6, 1.5 plus MgO, or 1.5 plus MgCl. The TRR 2.6 treatment showed increased (P < 0.05) DM, NDF, and N digestibilities when compared to all other treatments. Nitrogen digestibility decreased (P < 0.05) with the addition of supplemental Mg. No treatment differences in Mg, Ca, K, or P balance were recorded. The TRR 2.6 treatment had the greatest decrease (P < 0.05) in serum Mg after 5 d. Experiment 3 was a cafeteria study using a switchback design, 23 Angus heifers were weighed and randomly assigned to one of two locations (11 heifers in drylot, and 12 heifers on pasture) containing two mineral supplements (0.0% Mg and 10.0% Mg). The groups were rotated between locations after 15 d for 30 d of measurements. Individual mineral consumption (grams/d), feeder attendance (trips/d), and feeding duration (seconds/d) were measured using a GrowSafe® individual feeding system. Heifers consumed 119% more (P < 0.01) 0.0% Mg supplement each day than the 10.0% Mg. Heifers made almost twice as many (P < 0.01) trips to the feeder, and spent an additional 91.3 s consuming the 0.0% Mg than the 10.0% Mg. Total mineral intakes were 87.3 % greater (P < 0.01) when supplemented on pasture compared to drylot. During the first 15 d, total mineral intakes were higher (P < 0.01) than for the second 15 d.

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33

Aguilar, Michelle. « Ruminal Nitrogen Recycling and Nitrogen Efficiency in Lactating Dairy Cattle ». Thesis, Virginia Tech, 2012. http://hdl.handle.net/10919/76829.

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Excess nitrogen (N) excretion from animal agriculture results in reduced air and water quality, and poses a risk to human health. Although the dairy industry utilizes milk urea N (MUN) to monitor protein feeding and N excretion, phenotypic diversity among cows may influence MUN and thus bias feed management. An initial study using data from 2 previously published research trials and a field trial, observed that cow had a significant effect on MUN variation. Regression models, utilized to predict MUN, corrected for dietary nutrients and some animal effects, and thus the observed effect of cow on MUN variation may reflect genetic selection decisions of animals with either poor or efficient urea transport. A second trial observed that MUN and PUN concentrations were positively correlated with gut urea clearance, providing evidence for differences in urea transport activity among cows. The presence of urea transport variation suggests that current protein recommendations may not estimate true requirements. A third trial observed that animals fed sub-NRC levels of RDP and RUP had reduced N intake and excretion of fecal N, urinary urea-N, and MUN. Animals maximized N efficiency and had no loss in milk production, suggesting a possible overestimation of RDP and RUP in the current NRC prediction model. The present project provides evidence for phenotypic variation among cows, which may be partially explained by differences in urea transport activity. Future work confirming genetic variation among urea transporters may provide an opportunity to improve feeding management if cow urea efficiency is known.
Master of Science

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34

Bianchini, Waldmaryan. « Isótopos estáveis do carbono como indicativo da fase lactente-ruminante em bubalinos Murrah / ». Botucatu : [s.n.], 2008. http://hdl.handle.net/11449/95268.

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Resumo: Este estudo buscou determinar através da utilização dos isótopos estáveis do carbono a fase em que o bezerro já está apto para ser desmamado e capaz de consumir alimentos sólidos. Para isso foram coletadas ao longo do período experimental amostras de fezes e sangue, para monitorar o comportamento do turnover do carbono em quatro bezerros bubalinos que recebiam dieta C3 em cocho privativo durante amamentação e leite proveniente de búfalas que se alimentavam de pasto C4. As análises isotópicas foram realizadas no Centro de Isótopos Estáveis do Instituto de Biociências da UNESP, campus de Botucatu. Para mensurar o turnover do carbono nos tecidos em determinado intervalo de tempo, foi utilizado o método sigmoidal de regressão de Boltzmann ou a função exponencial do tempo. Os resultados isotópicos das amostras dos animais que foram submetidos à análise por meio do modelo de Boltzmann ou equação exponencial evidenciaram a dinâmica de consumo do grupo durante os primeiros dias de vida. A meia-vida nas fezes do animal 1091 foi de 224,8 dias e no animal 1093 foi de apenas 61,2 dias, no sangue apenas no animal 1093 foi possível determinar a meia-vida, que foi de 125,6 dias e no plasma sangüíneo a meiavida do animal 1091 foi de 63,8 dias, no animal 1093 foi de 88 dias e no animal 1094 foi de 53,3 dias. Portanto, pode-se concluir que fezes não podem ser consideradas marcadores de digesta confiáveis para as condições deste estudo, apenas como indicadores de consumo. Plasma e sangue total foram eficientes em determinar o tempo de desmame para bubalinos Murrah.
Abstract : This study it searched to determine through the use of stable isotopes of carbon the phase where the year-old calf already is apt to be weaned and capable to consume solid foods. For this samples of blood and faeces had been collected throughout the experimental period, to monitor the behavior of turnover of carbon in four buffaloes year-old calves that received privative C3 diet during breast-feeding and milk proceeding from buffalos that if they fed of C4 grass. The isotopic analyses had been carried through in the Steady Isotope Center of the Institute of Biociências of the UNESP, campus of Botucatu. To measure turnover of carbon in fabrics in determined time interval, the sigmoid method of regression of Boltzmann or the exponential function of the time was used. The isotopic results of the samples of the animals that had been submitted to the analysis by means of the model of Boltzmann or exponential equation had evidenced the dynamics of consumption of the group during the first days of life. The stocking-life in faeces of animal 1091 was of 224,8 days and in animal 1093 it was of only 61,2 days, in the blood only in animal 1093 was possible to determine the stocking-life, that was of 125,6 days and in the plasma sanguine the stocking-life of animal 1091 was of 63,8 days, in animal 1093 it was of 88 days and in animal 1094 it was of 53,3 days. Therefore, it can be concluded that faeces cannot be considered true markers of digestibility for the conditions of this study, as only indicating of consumption... (Complete abstract click electronic access below)
Orientador: Carlos Ducatti
Coorientador: André Mendes Jorge
Banca: Fabiana Ribeiro Caldara
Banca: Cyntia Ludovico Martins
Banca: Ciniro Costa
Banca: Alfredo Sampaio Carrijo
Doutor

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Kenna, Twila M. « Gluconeogenesis in the liver of growing and lactating ruminants : the influence of ration composition and stage of lactation ». Diss., Virginia Polytechnic Institute and State University, 1991. http://hdl.handle.net/10919/71147.

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Thirty six: Holstein bull calves were assigned to a 3X3 factorial design with ration physical forms of chopped hay (CH), ground hay (GR) and all concentrate (CONC) and rumen degradable nitrogen (RDN) of 30, 45 and 60%. Metabolic body weight, liver weight and blood glucose were greatest in CONC-fed calves. Neither dry matter nor ash content of liver tissue was affected by either physical form or RDN. Within physical form, protein content was highest and fat lowest in livers of CH-fed caIves. Within RDN, livers of calves feel 30% RDN rations had lowest protein and highest fat content. RDN percent had no effect on carbon dioxide production. Livers from CONC-fed calves produced significantly· (P<.05) more carbon dioxide from [1⁻¹⁴C}propionate and [U⁻¹⁴C}lactate.Glucose production from propionate and lactate was greatest for CONC-fed and 60% RDN-fed calves, although significant only from lactate within physical form. Interaction between ration physical form and RDN makes interpretation of propionate data difficult. In 30% RDN-fed calves both lactate and propionate metabolism was similar for GR- and CONC-fed animals. At 45 and 60% RDN rations, CONC- and CH-fed calves had similar gluconeogenic rates from propionate but glucose from lactate was significantly greater in livers of CONC-fed calves compared to GR- and CH-feet animals. Ten lactating and five dry Holstein cows were liver biopsied at various stages of lactation (30,60,90,120,180 days postpartum and dry) and when fed two rations, control ( 18% CF) or high concentrate (HI CONC, 10.5% CF). Lactating cows at 30 and 60 days and dry cows were fed the control ration. After 60 days half the cows remained on the control ration and half the lactating cows were changed to the HI CONC ration. Milk fat percent was depressed in cows fed HI CONC ration. Milk fat percent was depressed in cows fed HI COCC ration. HI CONC cows consumed more dry matter and due to the higher energy content reached a positive energy balance before control cows. Rumen fluid volatile fatty acid production was not affected by stage of Lactation or ration fed. Both plasma glucose and plasma insulin nonsignificantly increased as lactation progressed. Liver tissue protein did not change over lactation but increased when HI CONC ration was fed. Stage of lactation affected (P<.0002) propionate metabolism to carbon dioxide with higher production at 120 days compared to 180 days. By ration, HI CONC cows' livers produced more carbon dioxide than control cows’ livers. Feeding the HI CONC ration significantly increased labelled glucose production. Increased production of both labeled carbon dioxide and glucose by liver from cows fed HI CONC ration was nonsignificant when based on liver protein content. Carbon dioxide/glucose ratio was similar for lactating (>60 days) and dry cows. Cows early in lactation (30 days) had significantly lower carbon dioxide/glucose ratios, indicating a higher glucose production. Ration and stage of lactation are important factors in ruminant metabolism.. Gluconeogenesis, a pathway especially important in ruminants, is affected by both factors. In calves and cows, concentrate rations increased glucose production. Ration RDN, studied in calves, affected lactate metabolism to glucose. The liver of lactating cows showed a greater response (increase in glucose production) to stage of lactation than ration fed demonstrating the importance of energy balance on ruminant metabolism.
Ph. D.

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Edwards, Nicholas John. « Nitrogen assimilation by rumen microorganisms : a study of the assimilation of ammonia by rumen bacteria in vivo and in vitro ». Title page, table of contents and abstract only, 1991. http://web4.library.adelaide.edu.au/theses/09PH/09phe2657.pdf.

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Abazinge, Michael D. A. « Studies of methods of preserving and enhancing fermentation, nutritional value and palatability of seafood waste for feeding ruminants ». Diss., Virginia Polytechnic Institute and State University, 1986. http://hdl.handle.net/10919/49972.

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Wilson, John Richard. « Limitations to nutritive quality of forages : with special emphasis on tropical grasses ». Thesis, The University of Sydney, 1994. https://hdl.handle.net/2123/26860.

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The research to support the submission for the Degree, Doctorate of Science in Agriculture, under the above theme began in 1970 and has been aimed at understanding the prime limitations to obtaining high nutritive value in forages; in particular the tropical grasses which constitute the main feed base for ruminants in most tropical regions of the world. At the time when this research started, tropical grasses, from collation of published feed analyses, were recognised as poor animal feeds with low crude protein concentration and low dry matter digestibility. The generally low protein content was thought to be due to low soil nitrogen in the tropics, and a perception that most feeds analysed were probably old and very mature. Low digestibility was thought to result largely from the high light environment of the tropics, and the frequency of drought. These views were coloured by the fact that most early information originated from Africa. The characteristics of temperate grasses in protein content and digestibility were used as yardsticks of nutritive quality. Evaluation of nutritive value of feeds pre—1970’s was very much the domain of animal-oriented scientists, largely concerned with predicting quality (6. g. digestibility or intake) from proximate analysis of ground feed samples. My involvement as a plant-oriented scientist researching the basis for plant variation in nutritive quality attributes through understanding the interaction between growth, environmental and stress physiology of forage plants, and their anatomical/structural-functional features, was a somewhat novel approach at the time. My studies set out through glasshouse, controlled environment and field studies to systematically investigate the reasoning behind these general views. Firstly, to determine whether low protein content of tropical grasses was a consequence of low soil nitrogen or of the physiology of tropical grasses. Secondly, to assess whether low digestibility was a consequence of the features of a tropical growth environment or of special characteristics of tropical grass genera [as distinct from temperate grasses] associated with their physiology, morphology and anatomy. Several research outputs impinged significantly on my initial thinking. Deinum in the Netherlands in 1968 tested the effect of temperature on herbage digestibility, and Minson and McLeod in 1970 compared the digestibility of feeds from different world localities. Both works suggested that high growth temperatures lead to low feed digestibility. Hatch and Slack at the CSR David North Laboratory in Brisbane in the late 1960’s published their series of works on the special C4 photosynthetic system of tropical grasses. Whilst the initial impetus of my work was directed towards tropical grasses, many of the studies have compared and contrasted temperate and tropical forages, and in some instances grasses and legumes as the two main plant groups contributing to ruminant nutrition. Much of the research presented gives insight into basic understanding of the limitations to quality of forages in general, not just tropical grasses. This applies particularly to the influence of environment on forage quality, and to the later studies on the anatomy of plant tissues and structure of cell walls. The work presented is from research whilst a member of the CSIRO Division of Tropical Crops and Pastures in Brisbane. Research was also undertaken on visits to Wageningen, Netherlands in 1972, and again as a Visiting Professor in 1986, to the New Zealand Phytotron Complex at Palmerston North in 1974/5, to University of Georgia, Athens, Georgia, USA in 1980/1 as an Australian Meat and Livestock Research and Development Overseas Study Award Scholar, and to US Dairy Forage Research Centre, Wisconsin, USA in 1991 under the USA/Australian Bilateral Science Agreement. My research findings are presented for convenience under six sections. Papers within sections are presented in alpha-chronological order, and the numbers refer to the composite compilation of reprints to be submitted for the degree.

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Pinto, Márcia Marcila Fernandes. « Composição química e degradabilidade ruminal de fenos de leguminosas da caatinga ». Universidade Federal Rural do Semi-Árido, 2016. http://bdtd.ufersa.edu.br:80/tede/handle/tede/594.

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Aiming to evaluate the chemical-bromatological composition and ruminal degradability of dry matter (DM), crude protein (CP) and neutral detergent fiber (NDF) of the hay of legumes Catingueira (Caesalpinia pyramidalis, Tul), Sabiá (Mimosa caesalpiniifolia Benth), Jucá (Caesalpinia ferrea Mart. ex Tul), Canafístula (Senna spectabilis var. excelsa) and Feijão-de-rola (Macroptillium lathiroydes), were used three sheep (SPRD) with rumen fistulae, kept in collective pens, daily getting the studied plants associeted with Capim canarana (Echinochloa pyramidalis). The animals underwent adjustment period of seven days. The plants were sun-dried in the sun and crunched into a 4.0 mm sieve, and the samples were incubated in the same periods of 2, 6, 12, 24, 48, 72 and 96 hours using TNT bags weight 60, the dimensions of 10 x 10 cm. It were performed analyzes the chemical-Bromatological Legume. The experimental design was a randomized block with split plots. The leguminous plants Jucá and Sabiá had presented the highest crude protein concentrations (24,00 and 12,92%) and also the higher lignin content (8.28 and 7.8%). The effective degradability of dry matter Catingueira was the highest observed among the legumes studied with 52.93 values; 45.27 and 41.55% / h (2, 5 and 8 hours), respectively. The jucá legume, has showed higher values for potential degradability (72.47%) and degradability Effective of crude protein (50.13, 39.86 and 35.62%/h) for 2, 5 and 8 hours, respectively. The Feijão-de-rola showed higher effective degradability of fiber neutral detergent 42.56; 35.51 and 31.68%/h for passage rate of 2%/h; 5% / h and 8%/h, respectively. All legumes evaluated show good potential for use in animal feed due bromatological chemical-composition and degradability rates, with the exception of thrush, which showed low degradability coefficients for all the fractions DM, CP and NDF
Com objetivo de avaliar a composição químico – bromatológica e a degradabilidade ruminal da matéria seca (MS), da proteína bruta (PB) e fibra em detergente neutro (FDN) dos fenos das leguminosas Catingueira (Caesalpinia pyramidalis, Tul.), Sabiá (Mimosa caesalpiniifolia Benth), Jucá (Caesalpinia ferrea Mart. ex Tul), Canafístula (Senna spectabilis var. excelsa) e Feijão de rola (Macroptilium lathiroydes), foram utilizados três ovinos (SPRD) fistulados no rúmen, mantidos em baias coletivas, recebendo diariamente as plantas estudados mais a dieta composta de capim canarana (Echinochloa pyramidalis). Os animais passaram por período de adaptação de sete dias. As plantas foram secas ao sol e trituradas em peneira de 4,0 mm, sendo as amostras das mesmas incubadas nos tempos de 2, 6, 12, 24, 48, 72 e 96 horas, utilizando sacos de TNT gramatura 60, nas dimensões de 10 x 10 cm. Foram realizadas as análises químico-bromatologicas das leguminosas. O delineamento experimental utilizado foi em blocos ao acaso com parcelas subdivididas. As leguminosas sabiá e jucá apresentaram as maiores concentrações de proteína bruta (24,00 e 12,92%) e também os maiores teores de lignina, (8,28 e 7,8%). A Degradabilidade efetiva da matéria seca da catingueira foi a maior observada entre as leguminosas estudadas com valores de 52,93; 45,27 e 41,55%/h (2, 5 e 8 horas), respectivamente. A leguminosa jucá, apresentou maiores valores para Degradabilidade Potencial (72,47%) e Degradabilidade Efetiva da Proteína Bruta (50,13; 39,86 e 35,62%/h) para 2, 5 e 8 horas, respectivamente. O feijão-de-rola apresentou maior valor da degradabilidade efetiva da fibra em detergente neutro 42,56; 35,51 e 31,68%/h., para taxa de passagem de 2%/h; 5%/h e 8%/h, respectivamente. Todas as leguminosas avaliadas apresentam bom potencial para utilização na alimentação animal em função da composição químico- bromatológica e taxas de degradabilidades, com exceção da sabiá, que apresentou baixos coeficientes de degradabilidade para todas as frações MS, PB e FDN
2017-01-11

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Campbell, Mackenzie Andrew. « Interaction Of Stocking Density And The Feeding Environment In Lactating Holstein Dairy Cows ». ScholarWorks @ UVM, 2017. http://scholarworks.uvm.edu/graddis/776.

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Stocking density serves as a sub-clinical stressor impacting natural behavior and affective state of dairy cows. However, cows rarely experience stocking density as an isolated stressor. Understanding the effects of stocking density with additional management stressors such as low-fiber diets or feed restriction is the next step in alleviating stress and improving the well-being of lactating dairy cows housed in freestall barns. The overall goal of this dissertation was to evaluate the interaction of stocking density and the feeding environment on short-term production, behavioral, ruminal fermentation, and stress responses of lactating dairy cattle. The first two studies (Chapter 2 and 3) served as preliminary research for the main studies of this dissertation. The first study objective was to evaluate the effectiveness of using chopped wheat straw to reduce sub-acute ruminal acidosis (SARA) in order to formulate diets for the first main study. Treatments were low straw (0 kg dry matter (DM)/d; LS) and high straw (1.36 kg DM/d; HS). High straw appeared to effectively reduce SARA by lowering time below pH 5.8 with minimal impact on feed intake and rumination. The second study objective was to evaluate the effect of type of blood collection tube on haptoglobin concentration across two commercially-available haptoglobin assays and evaluate assay agreement in order to determine haptoglobin concentrations for the main studies. Lithium heparinized, sodium heparinized, and K2-EDTA plasma resulted in increased haptoglobin concentrations compared to serum using the Tri-Delta colorimetric assay, but no differences were observed using the Life Diagnostics ELISA assay. However, there was a lack of agreement between assays and further identification of a gold-standard assay is needed before analyzing haptoglobin for the main studies. The third study (Chapter 4) investigated the interaction of stocking density (100% and 142% of freestalls and headlocks) and source of forage fiber (no added straw and added straw at 3.5% ration DM). Treatments did not impact feed intake, but straw diets tended to reduce milk production. Increasing stocking density reduced lying time but increased efficiency of stall use. Though feeding and rumination times were unaffected, overstocking shifted the location of rumination away from the freestall. Increased stocking density tended to increase stress responses. Both greater stocking density and no straw diets increased SARA, and the combination of these stressors tended to exacerbate this pH response. Adding straw to the diet reduced the negative impacts of overstocking on ruminal pH. The fourth study (Chapter 5) evaluated the interaction of stocking density (100% and 142%) and feed access (5-h reduced feed access and no reduced feed access). Treatments had minimal impact on short-term feed intake and production. Overstocking affected behavior similar to responses observed in Chapter 4. Reducing feed access decreased feeding time, though cows altered feeding and rumination responses to maintain daily rumination. Both treatments shifted priorities for feeding and lying behavior, though increased stocking density had the larger impact. Though reduced feed access did not impact ruminal pH, an exacerbated response was observed when combined with increased stocking density. The combination of stocking density and feeding environment stressors exacerbate negative effects on biological function and should be avoided.

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Bouattour, M. Amine. « Effects of feeding different vegetal fat sources to increase conjugated linoleic acid in milk of small ruminants and interaction with fibrolytic enzymes ». Doctoral thesis, Universitat Autònoma de Barcelona, 2007. http://hdl.handle.net/10803/5681.

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El objetivo principal de la presente tesis doctoral fue estudiar la posibilidad de mejorar la calidad nutritiva de la leche de oveja y de cabra, y en particular la concentración de ácido linoleico conjugado (CLA) mediante la incorporación de diferentes fuentes de lípidos vegetales a la ración.
El primer capitulo fue realizado para investigar los efectos de la suplementación con Semillas Enteras de Lino (WLS) o de Aceite de Lino (LSO) sobre la producción y composición de leche, así como el perfil de ácidos grasos (AG) de leche y queso. Las concentraciones de AG de cadena media y de AG saturados fueron más bajas, y las de AG insaturados y de cadena larga más altas en la leche de los tratamientos con lino. El ácido alfa-linolénico aumentó más con la semilla que con el aceite, mientras que el CLA (ácido ruménico, RA) aumentó más con el aceite que con la semilla. En paralelo, el ácido trans-11 vaccénico (TVA) aumentó únicamente con el aceite. De manera general, la composición en AG de quesos curados (60 días de maduración) fue similar a la de la leche del correspondiente tratamiento experimental.
En el segundo capítulo se utilizaron 24 ovejas de raza Lacaune para estudiar los efectos de las semillas enteras de cártamo (WSF) sobre la producción y composición de leche, así como sobre su perfil de AG, en particular CLA. En la leche producida por el grupo WSF, las concentraciones de AG de cadena larga y de AG insaturados fueron más altas, mientras que las de AG de cadena corta y de AG saturados fueron más bajas. Las concentraciones de CLA (RA) y de TVA en leche fueron mayores en el grupo WSF.
En el tercer capítulo, se realizaron dos ensayos experimentales con el objetivo de estudiar los efectos de la inclusión del aceite de soja (SBO) y de un complejo de enzimas fibrolíticas (E) sobre la digestibilidad de los nutrientes de la ración y la producción y composición de leche. Cuando SBO se utilizó solo, no tuvo consecuencias sobre las digestibilidades de MS, MO y FND. El tratamiento E incrementó las digestibilidades de MS, MO y FND. Sin embargo, cuando fueron utilizados conjuntamente (SBO+E) el aceite de soja anuló las mejoras ofrecidas por E. En el experimento de ordeño, las concentraciones de ácido oleico, TVA, linoleico y CLA fueron más altas por efecto del aceite, con respuestas más evidentes en raza Lacaune que en Manchega. La adición de enzimas incrementó la producción de leche.
El cuarto capítulo consistió en un experimento llevado a cabo con 24 cabras Murciano-Granadinas con el objeto de estudiar los efectos de la suplementación con SBO sobre la producción y composición de leche, y su perfil de AG, especialmente de CLA y de TVA. La concentración de AG de cadena corta y media en leche se redujo, mientras que la de AG de cadena larga aumentó. SBO redujo el ratio de AG saturados/insaturados así como el índice de aterogenicidad. Comparado con el control, las concentraciones de CLA y TVA en la leche fueron triplicadas por efecto del aceite de soja.
En conclusión, los lípidos de origen vegetal incrementaron el CLA (RA) y el ácido trans-11 vaccénico, obteniéndose los incrementos más altos con la utilización de aceites vegetales, especialmente con aceite de soja en ovejas de raza Lacaune o en cabras Murciano-Granadinas. Por el contrario, las semillas enteras de lino permitieron un mayor aumento del ácido alfa-linolénico, de tipo n-3. A la dosis utilizada, el aceite de soja no afectó la digestibilidad de la fibra, pero anuló el efecto positivo de las enzimas observado sobre la digestibilidad.
The present Doctoral Thesis was carried out to study the possibility of enhance the nutritive quality of sheep and goat milk using the incorporation of different sources of vegetal fat to the diet.
The first experiment was performed to investigate the effects of feeding whole linseed (WLS) or linseed oil (LSO) to dairy ewes on lactational performance, milk and cheese fatty acids profile and CLA content. Short chain fatty acids (FA) remained unchanged while medium chain and saturated FA were decreased and large chain and unsaturated FA (including mono and poly-unsaturated FA) were increased by WLS and LSO. Feeding WLS was more useful on increasing milk alpha-linolenic acid content, while feeding LSO allowed a higher increase of rumenic acid. Similarly, trans-11 C18:1 (trans vaccenic acid or TVA), precursor of CLA, was only increased by LSO. Except for short chain FA, the FA profile of 60-d-old cheeses made from milk of the ewes receiving the experimental treatments was similar to the FA profile of the milk.
In the second study, a total of 24 Lacaune dairy ewes at 49±7 DIM were used to study the effects of adding whole safflower seeds (WSF) to the concentrate on dairy performance and Conjugated Linoleic Acid (CLA) in milk. Feeding WSF increased concentrations of long chain and unsaturated FA, and decreased short chain and saturated FA. Concentrations of rumenic (cis-9, trans-11 CLA) and TVA acids in milk were increased in animals fed WSF. In addition, WSF reduced the saturated/unsaturated FA ratio and the atherogenicity index of the milk fat, but increased the ratio n-6/n-3 FA.
In the third chapter, two experiments were performed to study the effects of feeding soybean oil (SBO) and a fibrolytic enzyme complex (E) on nutrients digestibility (trial 1) and lactational performance of dairy ewes (trial 2). When used alone, feeding SBO increased ether extract digestibility without varying the DM, OM and NDF digestibilities, while the E treatment increased DM, OM and NDF digestibilities. In contrast, when fed together with the enzyme complex, SBO reduced digestibilities of DM, OM and NDF, being the enzyme supplement unable to reincrease nutrients digestibility. In a milking trial, milk FA variations were higher in Lacaune than in Manchega ewes. Oleic acid, TVA, linoleic acid and CLA were increased.
The fourth chapter consisted in an experiment where a total of 24 Murciano-Granadina dairy goats were used to study the effects of feeding soybean oil (SBO) on lactational performance and milk fatty acids (FA), particularly CLA and TVA. Feeding SBO increased milk concentrations of linoleic, oleic and stearic FA. As a consequence, feeding SBO reduced the saturated to unsaturated FA ratio and the atherogenicity index, but increased the n-6/n-3 FA ratio. Compared with the control, milk contents of cis-9, trans-11 CLA and TVA in the SBO treatment were almost triplicated.
In conclusion, vegetal fat increased CLA (rumenic acid) and TVA, being the highest increases obtained in the case of feeding vegetal oils, particularly when using soybean oil in Lacaune ewes or Murciano-Granadina goats. In contrast, whole linseed grains enhance better the alpha-linolenic acid (n-3). Under the circumstances of our experiment, soybean oil did not affect fiber digestibility except when used together with the fibrolytic enzyme complex, in which case reduced DM, OM and fiber digestibilities.

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Upton, Erlanda. « Development and evaluation of polymer coated urea as a potential slow-release urea supplement for ruminants ». Thesis, Stellenbosch : Stellenbosch University, 1999. http://hdl.handle.net/10019.1/51199.

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Thesis (MScAgric)--Stellenbosch University, 1999.
ENGLISH ABSTRACT: The rate of hydrolysis of urea in the rumen of animals is a major limitation when considering the substitution of natural protein with urea in the formulation of rations. The aim of this study was to evaluate polymer coated urea prills with variable coating thickness and evaluate its potential as a slow-release NPN compound. A new slowrelease urea compound, made by coating prilled feedgrade urea with a co-polymer of urea-formaldehyde resin and a castor-coconut alkyd was initially evaluated for urea-nitrogen concentration in distilled water in order to evaluate its potential as a slow-release urea product for ruminants. Amino/alkyd or polyester blends are among the cheapest of the modern synthetic systems and are considered because it is non-toxic, low-cost, biodegradable and easy to manufacture. A 2 x 2 x 2 x 2 factorial design was used and 16 individual products were made and evaluated. The Wurster method was used to encapsulate urea prills. The slopes of the urea release curves represented the release rate of the encapsulated products and were compared to identify the process variables, which had an effect on release rate. Two of the coating variables, coating weight and alkyd: resin ratio, had a major effect (P = 0.0001) on the release rate of urea. The crushing strength of encapsulated products was significantly (P = 0.0001) higher than that of untreated urea. Results motivated the evaluation of the products in the rumen of sheep in terms of rumen ammonia and blood urea N concentrations. Four slow-release products were made after interpreting results from the first study, and differed on account of the coating weight and the composition of the co-polymer. Fifteen fistulated wethers were randomly allotted into 5 groups and intraruminally received an equivalent of 15g urea. Rumen ammonia and blood ammonia were taken at 0, 1, 2, 4, 6, 8, 12, 16, 20, 24, 36 and 48 h after administration of the various treatments. Slow release urea (SRU) resulted in significantly lower rumen ammonia peaks (P = 0.0001) than untreated urea, while the peaks were also significantly delayed. Untreated urea resulted in the maximum concentration at two hours after administration of the urea (P = 0.0685) while the SRU's reached a maximum at six hours after administration in the rumen. No significant differences between the four different SRU types were found. Responses in blood urea-N was similar to that observed for rumen ammonia nitrogen. The encapsulation was effective in decreasing the rate of ammonia release from the urea for up to six hours after administration. In a third trial four Dehne Merino wethers were used in a 2 x 2 Latin square design. They received a SRU product equivalent to 0.4 g urea per kg body weight orally. Rumen liquor and blood samples were taken at 0, 1, 2, 4, 6, 8, 12, 16, 20, 24, 36 and 48 h after intake. Difficulty was initially experienced with ingestion and palatability of the SRU products due to the strong formaldehyde and butanone odour present in the coating. The maximum rumen ammonia (NH3) concentration for the SRU were lower than that of untreated urea (17.5 mg N/dl vs. 66.9 mg N/dl). The time to reach blood urea levels also differed considerably (6 h vs. 24 h for blood urea nitrogen) between treatments. The encapsulation of urea prills shows potential solutions to reduce the solubility of urea and also reduce the hygroscopic nature of urea and improve the palatability and storage characteristics thereof. Keywords: Slow-release urea, encapsulate, copolymer, urea formaldehyde rumen ammonia, blood urea nitrogen, solubility, palatability, storage characteristics.
AFRIKAANSE OPSOMMING: Die vinnige tempo waarteen ureum in die rumen na ammoniak omgesit word, is die grootste beperking in die optimale benutting van ureum, as vervanging van natuurlike protein in herkouerrantsoene. Die doel van hierdie studie was om 'n stadig vrystellende ureumproduk te ontwikkel wat die rumenammoniakvlak gedurende 'n aansienlike periode van die dag bokant 'n sekere vlak kan hou. 'n Nuwe stadig vrystellende ureumproduk, vervaardig deur ureumkorrels met 'n kopolimeer van ureum-formaldehiedhars en 'n kastor-en klapperalkied te bedek, is geevalueer om die potentiaal as stadig vrystellende nie-protein stikstof (NPN)-produk vir herkouers te ondersoek. Die veiligheid, biodegradeerbaarheid, lae koste en maklike vervaardiging van amino/alkied-kopolimere maak dit een van die goedkoopste sintetiese sisteme om vir stadig vrystellende sisteme te oorweeg. 'n 2 x 2 x 2 x 2 Faktoriale antwerp is gebruik om 16 individuele produkte te vervaardig. Die Wurster-metode is gebruik om individuele korrels te enkapsuleer met die polimeer en die potentiaal van die produkte is aanvanklik geevalueer deur die ureumstikstofvrystelling in gedistilleerde water te meet. Die hellings van die vrystellingsgrafieke is vergelyk om die veranderlikes te bepaal wat die grootste invloed op die vrystellingstempo van ureum uit die ge·inkapsuleerde produkte het. Resultate dui dat twee verandelikes 'n betekenisvolle effek het op die vrystellingstempo, nl. dikte van die omhulsel, en die samestelling van die kopolimeer (P = 0.0001 en P = 0.0135, onderskeidelik) het. Die samedrukbaarheid van die ge ·lnkapsuleerde produkte was ook betekenisvol hoer (P = 0.0001) as die van onbehandelde ureumkorrels, wat lei tot verbeterde bergings- en hanteringseienskappe. lnterpetering van resultate lei tot die vorming van vier stadig vrystellende produkte. Vyf groepe van 3 volwasse rumengefistuleerde Dohnemerinohamels is in 'n proef gebruik om die potentiaal van die produkte verder te ondersoek. 'n Ekwivalent van 15 g ureum is direk in die rumen van elke dier geplaas en ammoniak-en bloed monsters is 0, 1, 2, 4, 6, 8, 12, 16, 20, 24, 36 & 48 ure na dosering geneem. Die stadig vrystellende ureumprodukte het 'n betekenisvol laer maksimum waardes vir beide ammoniak-en bloedstikstofureum getoon (P = 0.0001 ). Onbehandelde ureum het 'n maksimum rumenammoniakstikstof konsentrasie reeds twee ure na toediening bereik in vergelyking met ses ure vir die stadig vrysellende produkte. Geen betekenisvolle verskille in hierdie parameters is tussen die ge·lnkapsuleerde produkte gevind nie, terwyl geen interaksie is tussen hoofeffekte voorgekom het nie. In 'n derde proef is vier Dohnemerinohamels gebruik om die vrystellingstempos, in terme van rumenammoniak-en bloedureumstikstof te bepaal waar die stadig vrystellende produk en onbehandelde ureum direk aan die diere gevoer is . 'n Ekwivalent van 0.4 g ureum/kg liggaamsmassa is gevoer. Aanvanklik is inname- en smaakliksheidprobleme ondervind, moontlik as gevolg van die sterk butanoon-en formaldehiedreuk van die omhulsel. Die rumenammoniakstikstof het 'n laer maksimum (17.5 vs. 66.9 mg N/1 00 ml) as die van onbehandelde ureum gehad terwyl die tyd wanneer maksimum konsentrasie bereik word ook aansienlik later was. Die polimeer inkapsulering van ureumkorrels toon potensiaal as 'n stadig vrystellende ureumproduk deurdat dit die oplosbaarheid van ureum in die rumen verlaag. Bykomende voordele is dat die omhulsel die higroskopisiteit verlaag en die samedrukbaarheid verhoog, beide eienskappe wat die hantering-en bergingseienskappe bevorder. Sleutelwoorde: Stadig vrystellende ureum, enkapsulering, kopolimeer, ureumformaldehied, rumenammoniak, bloed ureum stikstof, oplosbaarheid, smaaklikheid, bergingseienskappe.

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Cuthbertson, Abla Zehour. « Effect of animal type or treatment on the efficiency of lean meat production and the fatty acid composition of meat : thesis submitted for the degree of Master of Agricultural Science ». Title page, summary and contents only, 1988. http://web4.library.adelaide.edu.au/theses/09A/09ac988.pdf.

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Includes bibliographical references (leaves 196-220) Studies the growth, body composition, feed intake of grazing animals, the use of anabolic agents, fatty acid composition of ruminants fats; and, the effect of saturated fat on human health.

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Uwituze, Solange. « The effects of feeding dry distiller’s grains with solubles on ruminal metabolism, growth performance, and carcass traits of feedlot cattle ». Thesis, Kansas State University, 2008. http://hdl.handle.net/2097/801.

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Master of Science
Department of Animal Sciences and Industry
James S. Drouillard
Three trials were conducted using dried distiller's grains with solubles (DDGS) to evaluate effects on feedlot performance, carcass characteristics, ruminal fermentation, and diet digestibility in cattle fed steam-flaked corn-based diets. In trial 1, crossbred yearling heifers were used in a finishing trial to evaluate interactions between corn-DDGS feeding levels and roughage source (alfalfa hay vs corn silage) in terms of impact on feedlot performance and carcass characteristics. Experimental diets were based on steam-flaked corn and contained 0% DDGS with 6% alfalfa hay (AH), 0% DDGS with 10% corn silage (CS), 25% DDGS with 6% AH, or 25% DDGS with 10% CS (DM basis). Results indicated no interaction between levels of DDGS and roughage source. Heifers fed DDGS as a partial replacement for steam-flaked corn had similar growth performance and carcass merit compared to heifers fed diets without DDGS. Corn silage and alfalfa hay were comparable roughages when a portion of steam-flaked corn was replaced with DDGS. The second trial was a companion metabolism study in which ruminal fermentation characteristics and diet digestibility were examined in 12 cannulated Holstein steers fed steam-flaked corn finishing diets with or without DDGS, using alfalfa hay or corn silage as roughage sources. Diets were similar to those fed in the performance study and consisted of steam-flaked corn with 0 or 25% DDGS (DM basis) and 6% AH or 10% CS (DM basis). Feeding DDGS decreased ruminal pH and ruminal ammonia concentrations, and digestion of DM and OM were less compared to diets without DDGS. The decrease in digestibility was largely attributable to poorer digestion of CP and, to a lesser extent, a reduction in starch digestion. The third study was designed to investigate effects of pH (5.0, 5.5, and 6.0) on in vitro fermentative activity by ruminal microorganisms from cattle adapted to a finishing diet containing 25% DDGS (DM basis). Higher pH led to greater dry matter disappearance in vitro (P < 0.01). DDGS can be an effective substitute for steam-flaked corn. Efforts to address low ruminal pH and low ruminal ammonia may prove beneficial for improving value of DDGS as cattle feed.

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Christensen, Rachael G. « Improvement of Nutrient Utilization Efficiency, Ruminal Fermentation and Lactational Performance of Dairy Cows by Feeding Birdsfoot Trefoil ». DigitalCommons@USU, 2015. https://digitalcommons.usu.edu/etd/4286.

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Forages containing condensed tannins (CT) have potential to reduce the environmental impact of dairy farming. In 3 studies, I hypothesized that feeding CTcontaining birdsfoot trefoil (Lotus corniculatus, BFT) would result in improved nutrient utilization and lactational performance of dairy cows compared with control forages of the respective experiments. Improved milk components, reduction in waste N, and overall improved N efficiency were hypothesized for BFT-fed cows compared to those cows fed alfalfa hay (Study 1) or grass-based diets (Study 2). In addition, a decrease in in vitro methane production and improved rumen fermentation due to diets based on BFT pasture and concentrate supplementation compared with grass pasture-based diets was the hypothesis of the third study. Study 1 showed BFT-hay diets improved lactational performance through increased energy-corrected milk yield and increased milk protein yield, resulting in improved N utilization efficiency compared with the alfalfa hay diet. Total volatile fatty acids concentration tended to increase, and greater microbial protein yield was exhibited by cows fed BFT compared to other diets tested. Therefore, BFT can replace alfalfa hay in dairy diets and showed improved feed and N utilization efficiencies and lactational performance. Study 2 determined that pasture nutrient content increased for BFT pasture compared to the mixed grass control, contributing to increases in milk yield most weeks during the 2-year study. Energy-corrected milk yield increased most weeks by BFT-grazed cows due to increased milk yield, although milk protein concentration was similar between treatments. Cows grazing BFT pasture increased N efficiency coupled with decreased milk urea N secretion in the first, but not the second year, suggesting an environmental advantage over traditional grass-based pastures depending on the effect of growing conditions on pasture quality at time of grazing. Study 3 showed that offering BFT pasture to continuous cultures without or with barley grain or total mixed ration supplements reduced methane production and altered rumen microbial populations. The reduced methane production on the continuous cultures was likely due to direct and/or indirect effects of CT on rumen microbiota. Overall, diets including BFT showed improved nutritive, lactational, and environmental benefits by decreasing N waste and methane production over typical alfalfa hay-based dairy diets and grass pastures.

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Kirk, David J. « Effects of feeding lasalocid and monensin upon mineral status of steers, and partial absorption and renal handling of minerals in sheep ». Diss., Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/54218.

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Studies were conducted to determine the effects of feeding lasalocid and monensin upon mineral status of ruminants, changes in digestive and renal physiology which bring about altered mineral status, and the effects of dietary K upon the actions of ionophores. Two 84-d grazing trials were conducted with steers fed no ionophore, 200 mg lasalocid, or 150 mg monensin. Monensin tended to increase gain of steers, but lasalocid had no effect. Feeding supplemental lasalocid and monensin altered Ca, P, Mg, Na, K, Cu, Fe and Zn status of grazing steers, but effects were not consistent. Twenty-four crossbred steers were individually fed in a 147-d finishing trial to study a possible K x monensin interaction. Steers were fed diets ad libitum containing .4% or 2.3% K, with or without 23 ppm monensin, dry basis. Feeding monensin with low K increased serum Na, Mg, inorganic P, Cu and Zn, but monensin fed with high K had no effect or decreased these serum minerals. Fifteen wethers, fitted with abomasal and ileal cannulae, were fed a basal diet alone or supplemented with 23 ppm lasalocid or monensin; Apparent absorption of Mg, K and Fe increased when ionophores were fed. Magnesium flow through the small and large intestines was decreased by lasalocid and monensin. Effects of lasalocid and monensin differed for metabolism, digestive tract flow and (or) partial absorption of Ca, P, Cu, Fe and Zn. Twelve ewe lambs were used in a renal clearance experiment. Lambs were fed a basal diet with no ionophore, 23 ppm lasalocid, or 23 ppm monensin, dry basis. Ionophores were fed starting on d 1 of the experimental period. Serial collections of blood and urine were made during d 1 and d 5 of the experimental period. Monensin reduced urine flow rate at d 1 and d 5. Feeding monensin lowered serum clearance and urinary excretion rates of Na and K at d 5. Serum clearance and urinary excretion rates of Ca were lower in sheep fed ionophores at d 1. Feeding monensin decreased serum clearance and urinary excretion rates of Cu at d 1. At d 5, urinary excretion rates of Zn were greater when lasalocid was fed, and lower when monensin was fed, compared to feeding no ionophore. These studies indicate that dietary lasalocid and monensin can alter mineral status of ruminants, although their effects may differ. The effects of ionophores may be dependent upon dietary K levels.
Ph. D.

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Lourençon, Raquel Vasconcelos [UNESP]. « Parâmetros ruminais e produtivos de cabras alimentadas com raspa de mandioca em substituição ao milho ». Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/126639.

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Made available in DSpace on 2015-08-20T17:10:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-07-03. Added 1 bitstream(s) on 2015-08-20T17:25:35Z : No. of bitstreams: 1 000844813.pdf: 750137 bytes, checksum: 455e0184a4c4de470cab844b2d958c25 (MD5)
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
O experimento foi conduzido com o objetivo de avaliar a substituição do milho pela raspa de mandioca na dieta de cabras Alpinas sobre o consumo de massa seca (MS), proteína bruta (PB), fibra em detergente neutro (FDN), carboidratos não fibrosos (CNF), nutrientes digestíveis totais (NDT) e energia metabolizável (EM), sobre a produção e composição do leite, digestibilidade aparente da MS, PB e FDN e também sobre o comportamento ingestivo dos animais em pastagem de capim-tobiatã. O experimento teve duração de 72 dias, em que foram utilizadas oito cabras em lactação, distribuídas em dois quadrados latinos (4 x 4) balanceados. Os tratamentos consistiram em níveis de 0, 33, 67 e 100% de substituição do milho pela raspa de mandioca no concentrado. A inclusão da mandioca proporcionou aumento linear no consumo de CNF e na digestibilidade da MS. A substituição não influenciou a produção e composição do leite e no comportamento ingestivo dos animais, dessa maneira, a raspa de mandioca pode substituir totalmente o milho no concentrado fornecido às cabras sem trazer prejuízos à produção de leite.
This study was conducted to evaluate the substitution of corn by cassava in supplementation of Alpine does on dry matter intake (DM), crude protein (CP), neutral detergent fiber (NDF), non-fiber carbohydrates (NFC), total digestible nutrients (TDN) and metabolizable energy (ME), yield and milk composition, apparent digestibility of DM, CP and NDF and also on the grazing behavior in tobiatã grass. The experiment lasted 72 days, were used eight lactating does, distributed in two Latin squares (4 x 4) balanced. The treatments were as following: 0, 33, 67 and 100% replacement of corn by cassava. The inclusion of cassava caused a linear increase in the NFC consumption and DM digestibility. The substitution had no effect on milk yield and feeding behavior of the animals in this way, cassava can replace totally the corn in the supplement provided to does without harming the production of milk.

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Lourençon, Raquel Vasconcelos 1981. « Parâmetros ruminais e produtivos de cabras alimentadas com raspa de mandioca em substituição ao milho / ». Botucatu, 2015. http://hdl.handle.net/11449/126639.

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Orientador: Heraldo César Gonçalves
Banca: Paulo Roberto de Lima Meirelles
Banca: Marco Aurélio Factori
Banca: Otavio Rodrigues Machado Neto
Banca: Kleber Tomasde Resende
Banca: Carla Maris Machado Bittar
Resumo: O experimento foi conduzido com o objetivo de avaliar a substituição do milho pela raspa de mandioca na dieta de cabras Alpinas sobre o consumo de massa seca (MS), proteína bruta (PB), fibra em detergente neutro (FDN), carboidratos não fibrosos (CNF), nutrientes digestíveis totais (NDT) e energia metabolizável (EM), sobre a produção e composição do leite, digestibilidade aparente da MS, PB e FDN e também sobre o comportamento ingestivo dos animais em pastagem de capim-tobiatã. O experimento teve duração de 72 dias, em que foram utilizadas oito cabras em lactação, distribuídas em dois quadrados latinos (4 x 4) balanceados. Os tratamentos consistiram em níveis de 0, 33, 67 e 100% de substituição do milho pela raspa de mandioca no concentrado. A inclusão da mandioca proporcionou aumento linear no consumo de CNF e na digestibilidade da MS. A substituição não influenciou a produção e composição do leite e no comportamento ingestivo dos animais, dessa maneira, a raspa de mandioca pode substituir totalmente o milho no concentrado fornecido às cabras sem trazer prejuízos à produção de leite.
Abstract: This study was conducted to evaluate the substitution of corn by cassava in supplementation of Alpine does on dry matter intake (DM), crude protein (CP), neutral detergent fiber (NDF), non-fiber carbohydrates (NFC), total digestible nutrients (TDN) and metabolizable energy (ME), yield and milk composition, apparent digestibility of DM, CP and NDF and also on the grazing behavior in tobiatã grass. The experiment lasted 72 days, were used eight lactating does, distributed in two Latin squares (4 x 4) balanced. The treatments were as following: 0, 33, 67 and 100% replacement of corn by cassava. The inclusion of cassava caused a linear increase in the NFC consumption and DM digestibility. The substitution had no effect on milk yield and feeding behavior of the animals in this way, cassava can replace totally the corn in the supplement provided to does without harming the production of milk.
Doutor

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Van, Do Thi Thanh. « Some animal and feed factors affecting feed intake, behaviour and performance of small ruminants / ». Uppsala : Department of Animal Nutrition and Management, Swedish University of Agricultural Sciences, 2006. http://epsilon.slu.se/200632.pdf.

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Battiston, Joziane. « Composição química e cinética de degradação ruminal determinada pela produção de gás in vitro da Aveia branca (Avena sativa L.) cultivar URS Guapa sob diferentes níveis de adubação nitrogenada ». Universidade Tecnológica Federal do Paraná, 2017. http://repositorio.utfpr.edu.br/jspui/handle/1/2511.

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CNPq; CAPES
Este trabalho consistiu em avaliar a composição química e a cinética de degradação ruminal da Aveia branca (Avena sativa L.) cv. URS Guapa submetida a diferentes níveis de adubação nitrogenada: 0, 60, 120 e 240 kg ha-1 de nitrogênio, em dois anos consecutivos, 2013 e 2014. Os dados obtidos das análises bromatológicas e os valores estimados para os parâmetros do modelo de cinética de degradação foram transformados pelo método de Box-Cox. O modelo estatístico foi ajustado por meio do PROC MIXED do SAS (versão 9.4) usando a máxima verossimilhança restrita (REML) e as variáveis com efeito significativo comparadas através do teste de Tukey-Kramer. Não houve efeito da adubação nitrogenada em nenhum dos anos de cultivo. Os valores observados para as variáveis bromatológicas da cultivar no ano de 2013 foram superiores (p<0,001) para Proteína Bruta (PB), Matéria Mineral (MM), Proteína Insolúvel em Detergente Ácido (PIDA), Carboidratos Solúveis (CHOs) e Carboidratos Não Fibrosos (CNF) em comparação com o ano de 2014. A composição da cultivar em 2014 tendeu a maiores teores de Fibra Insolúvel em Detergente Neutro (FDN), Lignina e Carboidratos Totais (CT). Não houve efeito significativo para os teores de Matéria Seca (MS) e Extrato Etéreo (EE) entre os anos de cultivo. Para os parâmetros da cinética de produção de gás in vitro, a cultivar no ano de 2013 apresentou os valores observados para o volume máximo de gás produzido pela degradação da fração solúvel de rápida digestão (Vf1) e para a taxa específica de produção de gás pela degradação da fração insolúvel potencialmente degradável de digestão lenta (k2) maiores (p<0,001) que 2014. Em 2014 foram observados valores superiores para o volume máximo de gás produzido pela degradação da fração insolúvel potencialmente degradável de digestão lenta (Vf2) e para a latência (L). O parâmetro k1, referente a taxa específica de produção de gás pela degradação da fração solúvel de rápida digestão não foi significativo em nenhum dos períodos experimentais avaliados. A cultivar, especialmente no ano de 2013, apresentou uma elevada qualidade nutricional evidenciada pelos teores de CNF e PB e pelos menores valores de FDN, o que torna o cultivo uma excelente opção para compor pastagens hibernais.
This work consisted in evaluating the chemical composition and kinetics of ruminal degradation of white oats (Avena sativa L.) cv. URS Guapa submitted to different levels of nitrogen fertilization: 0, 60, 120 and 240 kg ha-1 of nitrogen, in two consecutive years, 2013 and 2014. The data obtained from the bromatological analyzes and the estimated values for the parameters of the kinetic model of degradation were transformed by the Box-Cox method. The statistical model was adjusted using the PROC MIXED of the SAS (version 9.4) using the maximum restricted likelihood (REML) and the variables with significant effect compared through the Tukey-Kramer test. There was no effect of nitrogen fertilization in any of the growing years. The values observed for the bromatological variables of the cultivar in the year 2013 were higher (P <0.001) for Crude Protein (PB), Mineral Matter (MM), Insoluble Protein Acid Detergent (PIDA), Soluble Carbohydrates (CHOs) Fibrous (CNF) compared to the year 2014. The composition of the cultivar in 2014 tended to higher levels of Insoluble Fiber in Neutral Detergent (NDF), Lignin and Total Carbohydrate (CT). There was no significant effect on the contents of dry matter (DM) and ethereal extract (EE) between the years of cultivation. For the parameters of the in vitro gas production kinetics, the cultivar in the year 2013 presented the values observed for the maximum volume of gas produced by the degradation of the soluble fraction of fast digestion (Vf1) and for the specific rate of gas production by Degradability of the slow degradable fraction of slow digestion (k2) greater than that of 2014. In 2014 higher values were observed for the maximum volume of gas produced by the degradation of the insoluble fraction potentially degradable of slow digestion (Vf2) and for the Latency (L). The parameter k1, referring to the specific rate of gas production by the degradation of the soluble fraction of fast digestion was not significant in any of the evaluated experimental periods. The cultivar, especially in the year 2013, presented a high nutritional quality evidenced by the CNF and CP levels and the lower values of NDF, which makes the crop an excellent option to compose winter pastures.

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