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1

Pugh, Jamie A. "Prediction of optimal rumen degradable protein levels in no-roughage, corn-based feedlot diets." Diss., Columbia, Mo. : University of Missouri-Columbia, 2007. http://hdl.handle.net/10355/6277.

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Thesis (M.S.)--University of Missouri-Columbia, 2007.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on January 16, 2008) Includes bibliographical references.
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2

Leung, Stanley. "The effect of clinoptilolite properties and supplementation levels on swine performance /." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=82276.

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Clinoptilolite is a zeolite and an aluminosilicate that can be fed to swine in order to reduce nutrients being excreted because of their molecular sieving properties, high cation exchange capacities, and a high affinity for the ammonium ion (NH4+). Preliminary research has been carried out on utilizing zeolite's unique characteristics for dietary supplementation for livestock, however much of this research is limited and is still in its infancy.
The results from this study show that the zeolite with a particle size distribution either >250 mum or mixed (50% particles greater and smaller than 250 mum) adsorbed the most NH4+. Macro mineral and heavy metal release was similar among all particle size distributions tested, but varied between sources of zeolite. Handling properties of zeolite were not affected by moisture content or particle size. The feed trial indicated that zeolite supplementation, combined with a low crude protein and energy diet and at an inclusion level of 4%, showed potential as a feed additive in swine diets for the purposes of nutrient reduction. Nevertheless, zeolite seemed to have a greater impact on energy ingestion, as compared to crude protein. Even at 6% zeolite inclusion in the feed, hog muscle, kidney and liver tissues showed no significant increase in heavy metal contents, as compared to those fed any zeolite.
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3

Mullins, Chad Ryan. "Feeding high levels of wet corn gluten feed to dairy cattle." Thesis, Manhattan, Kan. : Kansas State University, 2009. http://hdl.handle.net/2097/1640.

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4

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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5

Harmon, Deidre Danielle. "Phosphorus excretion in beef steers as impacted by increasing levels of corn gluten feed." Thesis, Virginia Tech, 2014. http://hdl.handle.net/10919/50510.

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Overfeeding of phosphorus (P) is a contributing factor to P levels in surface waters. The objective of this study was to determine the impact of increasing levels of corn gluten feed (CGF) as a supplemental source of P on fecal P excretions. Eight Hereford steers (427±79 kg) were randomly assigned to one of four dietary treatments in a 4 x 4 replicated Latin square design. Steers were fed chopped grass hay ad libitum (0.13% P) and 0, 0.5, 1.0 or 1.5 kg/d of dried CGF pellets. All steers were supplemented with 0.91 kg/d beet pulp, 0.34 kg/d rumen-inert fat supplement and 18.14 g/d trace mineral salt. Urea was added to the respective diets at levels of 95.25, 72.57, 49.90, and 31.75 g/d to ensure equal dietary protein across treatments. Steers were housed individually and fitted with total fecal collection bags. Steers were adjusted to each diet for 9-d followed by a 5-d collection period. Following the final collection of each period, a 10 ml jugular blood sample was collected and analyzed to determine serum inorganic P. Dietary total P increased (P < 0.05) as CGF level increased: 8.72, 12.59, 16.75 and 20.88 g/d. Dry matter digestibility increased linearly (P < 0.05) as dietary P increased: 50.35, 53.66, 54.25 and 55.42%. Total P excretion increased linearly (P < 0.05) with increasing CGF level: 9.66, 11.71, 14.29, 16.96 g/day. Inorganic P excretion increased linearly (P < 0.05) with increasing CGF level: 4.11, 5.93, 8.36 and 9.92 g/day. Total P excretion was highly related (P < 0.05; r2 = 0.79) to inorganic P excretion. Serum inorganic P increased linearly (P < 0.05) with increasing dietary P content: 5.61, 5.87, 6.64 and 6.80 mg/dL. Fecal P increased as CGF level increased in steers fed varying dietary levels of P from plant sources. Management of P intake can be a strategic practice to reduce P fecal excretions in beef cattle.
Master of Science
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6

Forster, Lance Allen. "Nutritional value of flat pea hay fed to sheep at different levels." Thesis, Virginia Tech, 1988. http://hdl.handle.net/10919/43855.

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Two experiments were conducted with sheep to determine the nutritional value of 'Lathco' flatpea (Lathyrus sylvestris) hay. In experiment 1, a finishing trial was conducted with 50 group fed crossbred lambs (25 ewes and 25 wethers) fed diets consisting of 70% chopped forage and 30% ground corn grain for 70 d. Five pens of five wethers and five pens of five ewes were selffed diets in which the forage consisted of 100:0, 75:25, 50:50, 25:75, and 0:100 proportions of alfalfa (Medicago sativa L.) and flatpea hay. Feed efficiencies decreased linearly (P<.05) as flatpea increased in the diet. Linear decreases (P<.05) were obtained in kidney and pelvic fat, backfat, leg conformation, and yield grade with increased flatpea in the diet. Blood urea-N (BUN), ruminal pH and NH3-N increased (P<.005) as proportion of flatpea increased. Total volatile fatty acid (VFA) and acetate concentration decreased linearly (P<.005) and propionate, isovalerate, and valerate levels increased linearly (P<.01) with increased proportions of flatpea hay. In experiment 2, 30 wether lambs were fed diets consisting of 100:0, 75:25, 50:50, 25:75 and 0:100 proportions of chopped alfalfa and flatpea hays in a digestion trial. Neutral detergent fiber (NOE), acid detergent fiber (ADE), cellulose, hemicellulose and energy digestibilities decreased linearly (P<.Ol) with increased levels of flatpea hay. Nitrogen retention was not different between sheep fed the different diets. Apparent absorbtion and retention of Ca decreased linearly (P<.05) with increased level of flatpea hay Ruminal pH and NHa-N, and BUN increased linearly (P<.OOl) as flatpea was increased in the diet. Ruminal total VEA, acetate and acetate to propionate ratio decreased linearly (P<.001) and propionate, isobutyrate, isovalerate, and valerate levels increased linearly (P<.001) as level of flatpea increased.


Master of Science
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7

Alvarado, Mario D. "Fishmeal substituted for soybean meal fed at two TDN levels for lactating dairy cows." Thesis, Virginia Tech, 1986. http://hdl.handle.net/10919/45742.

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Thirty multiparous Holstein and twelve multiparous Jersey cows were used to determine the effect of diets (3x2 factorial) containing 0,1,2 kg of fish meal (FM) and energy levels of 70 and 75% TDN on milk production and composition. Basal diets contained 83% corn silage and 10.3% concentrate for the 70% TDN ration and 60% corn silage, 10.3% concentrate and 24.5% high moisture corn for the 75% rations. High moisture corn in the higher TDN diets decreased both acid and neutral detergent fiber, and increased dry matter content. Nitrogen degradability was lower in the higher TDN rations and decreased with increasing fishmeal levels. Dry matter degradability tended to be similar for all diets. Milk and FCM production was similar for all diets. Milk fat percentage was similar for TDN levels but decreased as fishmeal level increased. Milk protein percentage increased with 75% TDN but was not affected by fishmeal. Kilograms of milk protein produced followed a trend similar to milk protein percentage. Dry matter intake was higher with higher TDN diets, but tended to be lower during the first 4 weeks of the study with increasing levels of fishmeal. Bodyweight fluctuated during the experiment and followed a pattern similar to dry matter intake. Blood plasma urea concentration was similar for all diets.
Master of Science
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8

Saavedra, Aracelli Pinelli. "Vitamin E and vitamin C supplementation of sows in a hot environment : effects on reproductive performance, piglet tissue levels and aspects of immune status." Thesis, University of Aberdeen, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369542.

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Summer and winter experiments were carried out to investigate the effects of dietary supplementation with vitamin E and vitamin C of sows in hot environments on reproductive performance, placenta transfer, piglet tissue vitamin E content and some indicators of immune status of sows and their litters. In summer, sows were given the following treatment diets: control, vitamin C 1g/day, vitamin C 10g/day, vitamin E 200 mg/kg feed, vitamin E 400 mg/kg fed, and combined vitamins (vitamin E 200 mg/kg feed + vitamin C 1 g/day). In winter, sows were given the following treatment diets: control, vitamin C 10g/day, vitamin E 500 mg/kg feed, combined vitamins (vitamin E 500 mg/kg/feed + vitamin C 10g/day). Data show that vitamin E had an effect on growth, but not on reproductive performance. Placental vitamin E concentrations were low but increased with dietary vitamin E supplementation. Vitamin E supplementation resulted in an increase in vitamin E content of sow plasma, piglet serum, colostrum and milk and piglet tissues. Supplementation with vitamin E and vitamin C had no consistent effect on parvovirus titer in sows. The relationship between sow plasma vitamin C and vitamin E concentrations and lymphocyte proliferation was not clear. Total Igs and IgG concentrations in piglet serum at weaning were significantly increased by the combined vitamin treatments. However, vitamins supplementation did not appear to have any effect in IgG colostrum. IgA concentration in milk was increased by the high level of vitamin E supplemented in the summer but not in the winter experiment.
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9

Du, Plessis J. J. P. (Johannes Jacobus Pieter). "The effect of different dietary levels of energy and protein on the production and body composition of broiler breeders." Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/51966.

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Thesis (MScAgric)--University of Stellenbosch, 2000
ENGLISH ABSTRACT: A flock of 500 Hybro broiler breeders were employed to study the effect of different levels of protein and energy on production and body composition. The daily lysine intake of the birds were 900, 1050, 1200 and 1350 mg respectively, each fed in diets with a daily energy intake of 1800 and 2000 kJ ME to provide a 4 x 2 factorial design. Lysine was used as the reference amino acid in the experiment and all other amino acids were kept in a constant ratio in every experimental diet. The total production was divided into 3 periods of 13 weeks each (week 23 - 35; week 36 - 48 and week 49 - 61) to determine the effect of the treatments over time. Production was evaluated by hen day production; egg weight (g/egg); egg mass (g/day); fertility; hatchability; chicks/hen/week; feed conversion and day old chick weight. Hen day production was significantly (P < 0,05) lower at the high energy intake for period week 49 to 61. Energy and protein levels significantly increased egg weight. Effect of protein was consistent during all three periods of production. Egg mass output had a significant (P < 0,05) response to increasing levels of protein for the total period of production. The birds on the high energy diet produced a significant higher egg mass per hen during the first period of production (week 23 - 35). Hatchability was reduced (P < 0,05) by the higher energy intake for the total period of production and this effect was very significant (P < 0,01) during the final period of production. Similar to hen day production, the higher energy had a significant (P < 0,05) negative effect on the amount of chicks produced. The well-known correlation between egg weight and chick weight was confirmed with the regression equation: Chick weight = 10,5 + 1,22 x Egg weight. Both energy and protein had a significant (P < 0,01) positive effect on chick weight. The feed conversion was lower at increasing levels of amino acid intake (P < 0,01). Higher energy intake significantly (P < 0,05) increased hen weight and protein had a very significant effect during the first period of production (P < 0,01). The isotope dilution technique (tritiated water) was used to estimate the body composition of the breeders. This was done at 5 different periods (week 27, 35, 43, 52 and 61) of the production period to establish changes in requirements over time. Significant correlation were found between carcass moisture and waterspace (R2 = 0,76); fat % and carcass moisture (R2 = 0,78); protein % and waterspace (R2 = 0,35) and fat % and waterspace (R2 = 0,46). The regression equations obtained from these correlation were employed to determine excess energy and lysine consumed at different ages. Energy requirements were calculated according to the effective energy (EE) system and the conventional ME system. According to effective energy the lower energy intake was not sufficient and the maximum requirement was calculated to be 1942 kj EE/day. The metabolizable energy calculations indicated sufficient intakes at every treatment with the maximum requirement 1746 kj ME/day. The lysine requirement was found to be in excess of 1050 mg lysine per day. The recommendation for daily lysine intake is 1200 mg/day and the energy intake of breeders should be 1900 to 2000 kj ME/day from week 23 to 35 and can be reduced to 1800 kj ME/day in the final period of production.
AFRIKAANSE OPSOMMING: Om die effek van verskillende vlakke energie en proteïen op produksie en liggaamsamestelling te ondersoek is 'n trop van 500 Hybro braaikuiken teelouers gebruik. Die daaglikse lisien inname van die henne was onderskeidelik 900, 1050, 1200 en 1350 mg, wat elk by 'n daaglikse energie inname van 1800 en 2000 kJ ME verskaf is, in 'n 4 x 2 faktoriale ontwerp. Alle aminosure is in 'n konstante verhouding met die verwysings aminosuur lisien in die rantsoen ingesluit. Om te evalueer of daar veranderinge oor 'n tydperk plaasvind weens die verskillende behandelings is die produksie periode in drie periodes van 13 weke elk verdeel (week 23 - 35; week 36 - 48 en week 49 - 61). Die produksie standaarde wat gemeet is, is hen dag produksie, eiergewig (g/eier), eiermassa (g/dag), vrugbaarheid, uitbroeibaarheid, kuikens/hen/week, voeromset en dagoud kuikenmassa. Hen dag produksie was betekenisvol (P < 0,05) laer by die hoër energie innames in die laaste periode van 49 tot 61 weke. Energie en proteïen het eiergewig betekenisvol (P < 0,01) verhoog. Die effek van hoër vlakke proteïen was konstant in alle produksie periodes. Die daaglikse eiermassa (g/dag) het ook saam met stygende vlakke proteïen verhoog en hierdie effek was vir die totale periode van produksie. Energie het die eiermassa in die eerste periode van produksie (week 23 - 35) verhoog. Uitbroeibaarheid is verlaag (P < 0,05) vir die totale periode van produksie deur die hoër energie inname en die effek was selfs groter (P < 0,01) in die finale periode van produksie. In ooreenstemming met die hen dag produksie is die aantal kuikens geproduseer negatief beïnvloed deur die hoër energie inname (P < 0,05). Die korrelasie wat bestaan tussen eiermassa en kuikenmassa is bevestig deur die regressie: Kuikenmassa = 10,5 + 1,22 x Eiermassa. Energie en proteïen het kuikenmassa betekenisvol (P < 0,01) verhoog. Voeromset was laer by stygende vlakke van proteïen inname (P < 0,01). Die hoër energie inname het henmassa ook betekenisvol (P < 0,05) verhoog en proteïen het dieselfde effek slegs in die eerste periode van produksie gehad (P < 0,01). Die liggaamsamestelling van teelhenne is bepaal met behulp van die isotoop verdunnings tegniek (tritium water). Dit is bepaal op 5 verskillende stadiums in die produksie periode (week 27, 35, 43, 52 en 61) om die moontlike verandering in behoeftes oor tyd vas te stel. Betekenisvolle korrelasies is gevind tussen karkasvog en die waterspasie (RZ= 0,76); vet % en karkasvog (R2 = 0,78); proteïen % en waterspasie (R2 = 0,35) en vet % en waterspasie (R2 = 0,46). Die regressie vergelykings van hierdie korrelasies is gebruik om die hoevelheid surplus energie en lisien ingeneem te bepaal. Die" effective energy" sisteem en die konvensionele ME sisteem is gebruik in die bepaling van energie behoeftes. Volgens die " effective energy" was die energie inname nie voldoende by die laer energie innames nie en die maksimum behoefte is bereken as 1942 kJ EE/dag. Die maksimum energie behoefte volgens metaboliseerbare energie is bereken as 1746 kj ME/dag. Die lisien behoefte moet hoër as 1050 mg/dag wees. Die aanbeveling van die daaglikse lisien inname is 1200 mg/dag en die energie inname moet 1900 tot 2000 kj/dag wees tot 35 weke produksie en kan daarna verlaag word na 1800 kJ ME/dag.
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10

Van, der Westhuizen Liana. "The effects of fumonisins on sphinganine and sphingosine levels in hepataocyte cultures, experimental animals and humans." Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/51973.

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11

Kennel, Phyllis D. "The effect of exercise and fish oil supplements on the blood lipid levels of the hamster." Thesis, Virginia Tech, 1989. http://hdl.handle.net/10919/46044.

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The effect of aerobic exercise and fish oil supplements on plasma lipid parameters was investigated in the hamster. The hamsters were fed a basal hypercholesterolemic purified diet (0.1% cholesterol, 15% fat) to elicit an elevated lipid response. Fifty-six hypercholesterolemic hamsters were divided into four groups: control, swimming (trained up to one hour every other day), daily fish oil supplementation (.35g/kg/day omega-3), and a swimming/fish oil combination. The effect of these treatments on plasma TC, TG and pooled samples of plasma HDL-C, HDL2â C, LDL-C and VLDL-C was studied over 12 weeks. All hamsters had a significant increase in body weight. Feed intakes increased at 6 weeks and then declined over the second 6 weeks, but remained above the beginning levels.


Master of Science
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12

Hannon, Robert Logan, of Western Sydney Hawkesbury University, Faculty of Agriculture and Horticulture, and School of Agriculture and Rural Development. "An evaluation of bentonite feed additives in horses and dogs and a reflection on the research process." THESIS_FAH_ARD_Hannon_R.xml, 1996. http://handle.uws.edu.au:8081/1959.7/738.

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This thesis reports on investigations into the influence of diet and a bentonite feed additive on blood parameters in the horse, and the effect of a bentonite feed additive on the process of digestion in the dog. In addition, the methodology of scientific research is examined, and reflections of learning experiences arising from contact with the Hawkesbury approach described. A high-concentrate low-roughage diet, consisting by weight of 70% oats and 30% lucerne chaff, when fed to horses was shown to influence blood red cell levels and blood L-lactate levels compared to three diets of equivalent energy content but reduced proportion of concentrate. Other blood parameters measured included pack cell volume, total plasma protein, total and differential white blood cell count. These demonstrated no significant alteration with diet. The inclusion of bentonite feed additive in a kibble and mince diet fed to dogs was demonstrated to improve the digestion of dry matter and organic matter components of the diet compared to the unmedicated control diet. Inclusion of bentonite food additive in the diet was also associated with an improvement in degree of stool formation and reduction in faecal odour. Part B of the thesis documents the learning experience developed from involvement in the Masters program and reflection on the research studies undertaken. A model for improved reductionist research is described.
Master of Science (Hons) (Systems Agriculture)
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13

Strydom, Marline. "The effect of different levels of supplementary feed on the production of finisher ostriches (Struthio camelus) grazing irrigated lucerne (Medicago sativa) pastures." Thesis, Stellenbosch : University of Stellenbosch, 2010. http://hdl.handle.net/10019.1/5234.

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Thesis (MScAgric (Animal Sciences))--University of Stellenbosch, 2010.
ENGLISH ABSTRACT: The purpose of this study was to evaluate the production of slaughter ostriches in a grazing environment at different levels of supplementary feed. Two grazing trials were conducted. In the first trial, one group of finisher ostriches (six months old) was put into a feedlot and received a complete finisher diet. The other four groups were allowed to graze lucerne pasture (stocking rate of 15 birds/ha) with 1500, 1000, 500, and 0g supplementary feed/bird/day. Pasture production and intake were measured. There was no difference (P >0.05) between the end mean live weights of the feedlot ostriches and those two grazing groups receiving 1500 or 1000g supplementation. The average daily gain (ADG) of the group receiving 1000g supplementation was lower (P <0.05) than the ADG of the group receiving 1500g supplementation, but all three groups reached a mean target slaughter weight of 95kg within the 154 days of the study. Therefore, pastures together with the correct supplementation (at least 1000g/bird/day) can replace complete feeds in the finishing phase of slaughter ostriches and can play an important role in the production of these birds. For lucerne intake, a quadratic relationship (P <0.01) was found between pasture dry matter (DM) intake (g/bird/day) and supplementary feed intake (g/bird/day). The maximum lucerne intake level (1692.8g/bird/day) was achieved at 619.6g supplementary feed/bird/day. In the second grazing trial, finisher ostriches were allowed to graze lucerne pastures at two different stocking rates (10 and 15 birds/ha) while receiving either 0 or 800g supplementary feed/bird/day. Ostriches receiving supplementation had higher (P <0.05) mean end live weights than ostriches receiving no supplementation. Ostriches receiving supplementation reached a mean target slaughter weight of 95kg within the timespan of the trial, but ostriches receiving no supplementation did not. Stocking rate had no influence on mean end live weight of the birds. An interaction (P <0.05) was found between the level of supplementation and stocking rate for ADG of the birds. Stocking rate influenced ADG only for birds receiving no supplementation. As stocking rate increased, ADG of birds receiving no supplementation declined. Results of the pasture data indicated an increasing level of replacement of grazed lucerne DM by supplementary feed as the trial progressed and this was more pronounced at the higher stocking rate of 15 birds per hectare. A high stocking rate seems to have had a gradual depressing effect on lucerne DM production, while the less severe levels of defoliation at a lower stocking rate promoted lucerne DM production. A digestibility trial was conducted with mature ostriches (12 months old) to investigate the effect of supplementation on intake and digestibility of nutrients, as well as to investigate the substitution effect that ostriches may display when they receive supplementary feed in addition to grazing. The same dietary treatments as in the first grazing study were given to ostriches while they were kept in metabolism crates. These diets were also fed to 20-week old roosters to obtain energy values for these diets for roosters. These energy values would be used to predict ostrich energy values for the same diets by means of a regression equation. For the roosters, each diet treatment was mixed with 50% maize to prevent digestive disorders and ensure maximum feed intake. Ostriches started to substitute supplementary feed for pasture when supplementation was supplied at levels higher than 62% (i.e. 1000g supplementary feed/bird/day) of total feed intake. For each increase of 100g in supplementary feed intake, pasture was replaced at a rate of 4.9%. Higher (P <0.05) total feed intakes were reached by ostriches if they grazed lucerne pastures and received supplementation than if they grazed pasture alone. Pasture grazing alone had lower (P <0.05) dry matter digestibility (DMD) and apparent metabolizable energy (AME) values for both ostriches and roosters than if pastures were supplied with a supplement. A significant stepwise regression could not be computed for the prediction of ostrich AME values from rooster AME values. The economics of different feeding systems (extensive versus intensive) were evaluated with an economic analysis, which was based on the same materials and methods and results of the first grazing trial. A margin above feed cost (MAFC) analysis was performed to evaluate the economic viability of the different feeding systems. The present value (PV) of the MAFC for the pasture-based system with 1000g/bird/day supplementation was only 8.3% lower than that of the feedlot system over a period of six years, while the PV of the cost of the same pasture-based system was 78.4% lower than that of the feedlot system. Birds finished on lucerne pasture with 1000g supplementation led to a saving of 57% in feeding costs if compared to a feedlot system. A sensitivity analysis of the MAFC revealed that the pasture-based system was less sensitive to changes in feeding costs than the feedlot system. Therefore, the unique circumstances of each ostrich producer will play a role in the decision whether to raise ostriches in a feedlot or on pastures.
AFRIKAANSE OPSOMMING: Die produksie van slagvolstruise in ‘n ekstensiewe weidingsstelsel met verskillende vlakke van aanvullende voeding is gedurende hierdie studie ge-evalueer. Twee weidingsstudies is uitgevoer. In die eerste studie is een groep afrondingsvolstruise (ses maande oud) in ‘n voerkraal geplaas en ‘n volledige afrondingsdieet gevoer. Die ander vier groepe is op besproeide lusernweiding geplaas (teen ‘n weidigtheid van 15 voëls/ha) en het onderskeidelik 1500, 1000, 500 en 0g aanvullende voeding/voël/dag ontvang. Weidingproduksie en -inname is gemeet. Daar was geen verskil (P >0.05) tussen die eindgewigte van die voerkraal volstruise en dié van die weidende voëls wat onderskeidelik 1500 en 1000g aanvullende voeding ontvang het nie. Die gemiddelde daaglikse toename (GDT) van die groep weidende voëls wat 1000g aanvullende voeding ontvang het was laer (P <0.05) as die GDT van die groep weidende voëls wat 1500g aanvullende voeding ontvang het, maar al drie hierdie groepe het ‘n gemiddelde teiken slaggewig van 95kg bereik binne die 154 dae van die studie. Weiding, tesame met die korrekte aanvullende voeding (van ten minste 1000g/voël/dag) kan volvoer rantsoene in die afrondingsfase van slagvolstruise vervang en kan dus ‘n belangrike rol speel ten opsigte van die produksie van hierdie voëls. Vir lusern inname is ‘n kwadratiese passing (P <0.01) tussen weiding droë materiaal (DM) inname (g/voël/dag) en aanvullende voeding inname (g/voël/dag) gevind. Die maksimum lusern inname (1692.8g/voël/dag) is bereik wanneer voëls 619.6g aanvullende voeding/voël/dag ingeneem het. In die tweede weidingsstudie, is afrondingsvolstruise (6 maande oud) toegelaat om lusern te bewei teen twee verskillende weidigthede (10 en 15 voëls/ha) en het ook 0 of 800g aanvullende voeding/voël/dag ontvang. Volstruise wat aanvullende voeding ontvang het, het hoër (P <0.05) gemiddelde eindgewigte bereik as volstruise wat geen aanvullende voeding ontvang het nie. Volstruise wat aanvullende voeding ontvang het, het ook die teiken slaggewig van 95kg bereik binne die tydsduur van die studie, terwyl die volstruise wat geen aanvullende voeding ontvang het nie, nie daarin kon slag nie. Weidigtheid het nie ‘n invloed (P >0.05) gehad op die eindgewigte van die voëls nie, maar ‘n interaksie (P <0.05) is gevind tussen vlak van aanvullende voeding en weidigtheid wat GDT van die voëls betref. Weidigtheid het GDT beïnvloed slegs vir volstruise wat geen aanvullende voeding ontvang het nie. Soos die weidigtheid van die voëls wat geen aanvullende voeding ontvang het nie, toegeneem het, het die GDT van hierdie voëls afgeneem. Ontleding van die weidingsdata het ‘n toenemende vlak van verplasing van die weiding met aanvullende voeding getoon soos die studie gevorder het en dit was meer merkbaar by die hoër weidigtheid. Die hoër weidighteid het ook gelei tot ‘n geleidelike afname in lusern DM produksie, terwyl die minder aggressiewe vlakke van ontblaring by die laer weidigtheid lusern DM produksie bevorder het. ‘n Verteringsstudie is gedoen met volwasse volstruise (12 maande oud) om die invloed van aanvullende voeding op inname en verteerbaarheid van nutriente te toets, asook om die substitusie effek wat volstruise mag toon wanneer hulle aanvullende voeding ontvang op weiding, te ondersoek. Dieselfde dieet behandelings as in die eerste weidingsstudie is vir die volstruise gegee terwyl hulle in metabolisme kratte aangehou is. Hierdie diëte is ook aan 20-week oue hane gevoer om die energie waardes van die diete vir hane te verkry. Hierdie energiewaardes sal dan gebruik word om volstruis energiewaardes te voorspel vir dieselfde diëte met behulp van ‘n regressie vergelyking. Vir die hane is elke dieet gemeng met 50% mielies om inname te handhaaf en spysverteringsstoornisse te voorkom. Volstruise het weiding begin verplaas met aanvullende voeding sodra die vlak van aanvullende voeding hoër as 62% (d.i. meer as 1000g aanvullende voeding/voël/dag) van die totale inname van die voëls was. Vir elke 100g toename in aanvullende voeding, word weiding verplaas teen ‘n tempo van 4.9%. Weiding, tesame met aanvullende voeding, het gelei tot hoër totale droë material (DM) voerinnames by volstruise as wanneer weiding alleen beskikbaar was. Wanneer weiding alleen voorsien was, was daar laer (P <0.05) verteerbaarhede van DM en waarskynlike metaboliseerbare energie (WME) waardes vir beide volstruise en hane as wanneer die weiding voorsien word met aanvullende voeding. Geen betekenisvolle stapsgewyse regressie kon gevind word om volstruis energie waardes uit hoender energie waardes te voorspel nie. Die ekonomie van verskillende sisteme (ekstensief versus intensief) is in hierdie studie vergelyk en is gebaseer op dieselfde materiaal en metodes en resultate van die eerste weidingsstudie. ‘n Marge bo voerkoste analise is gebruik om die ekonomiese lewensvatbaarheid van die sisteme met mekaar te vergelyk. Die huidige waarde van die marge bo voerkoste van die weidingssisteem waar 1000g aanvullende voeding gevoer word was 8.3% laer as dié van die voerkraal sisteem oor ‘n periode van ses jaar. Daarteenoor was die huidige waarde van die koste van dieselfde weidingssisteem 78.4% laer as dié van die voerkraal sisteem. Die weidingssisteem waar volstruise 1000g aanvullende voeding ontvang het, het ‘n besparing van 57% in voerkoste getoon wanneer dit met die voerkraal volstruise vergelyk is. ‘n Sensitiwiteitsanalise van die marge bo voerkoste het getoon dat die weidingssisteem minder sensitief is vir wisselende voerkoste as die voerkraal sisteem. Die unieke omstandighede van elke produsent sal ‘n rol speel in sy keuse om volstruise op weiding of in ‘n voerkraal af te rond.
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14

Archibeque, Shawn Louis. "Finishing diets with elevated levels of alpha-linolenic acid increase feed efficiency and adipose lipogenesis but do not alter beef carcass quality." Diss., Texas A&M University, 2003. http://hdl.handle.net/1969/154.

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15

Goodarzi, Boroojeni Farshad [Verfasser]. "The Effects of Different Thermal Treatments and Organic Acids Levels in Feed on Nutrient Digestibility and Gut Microbiota in Broilers / Farshad Goodarzi Boroojeni." Berlin : Freie Universität Berlin, 2014. http://d-nb.info/1058858343/34.

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16

Teague, Paul David. "The effect of two levels of dietary ractopamine hydrochloride (Paylean®) supplementation on growth performance, feed efficiency and quantitative carcass traits in finisher gilts." Diss., University of Pretoria, 2016. http://hdl.handle.net/2263/60863.

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Ractopamine hydrochloride (RAC) has been used in the pig production industry for over 30 years. RAC is a beta-adrenergic agonist which is supplemented in the feed during the last 28 days prior to harvesting in finisher pigs to modify the pig's metabolism such that nutrients are redirected to favour muscle accretion rather than adipose deposition, and hence improve growth efficiencies, feed utilisation and carcass revenues. The objective of this study was to investigate the effect of dietary ractopamine (Paylean®) supplementation at levels of 0, 5, and 10 mg.kg-1 (hereafter referred to as 0-RAC, 5-RAC, and 10-RAC respectively) on animal growth performance, efficiency and carcass characteristics including daily voluntary feed intake, feed efficiency, absolute daily growth rate (ADG) and daily live weight gain, and backfat thickness for the last 27 days in finishing gilts. In this 27-day study, a homogenous group of 71 grower gilts (LW = 43 ± 1 kg) were pre-selected at a source farm. The gilts were then housed in similar and equally sized group pens at the Hatfield experimental facility of the University of Pretoria and fed a standard maize-soya oilcake based grower ration formulated to contain 0.94% standardised ileal digestible Lys (1.05% total Lys) and 14.01 MJ ME kg-1 during the 28 day pre-adaptation phase. From these gilts, individuals were weighed and 58 gilts selected (average LW = 68.7 ± 4.3 kg), and placed into individual pens and the same diet for 7 days (adaptation phase), afterwhich they were assigned to 1 of 3 treatments in a completely randomized block design with 19, 19, and 20 replicate pens per treatment. The pigs were then fed a standard maize-soya oilcake finisher (treatment) diet containing either 0-RAC, 5-RAC or 10-RAC for 27 d before harvesting. All treatment diets were formulated to contain 1.02% standardised ileal digestible Lys (1.13% total Lys) and 13.96 MJ ME kg-1. Individual pig LW, P2 thickness and pen feed disappearance were recorded weekly to determine LW changes, ADG, ADFI, and G:F. After 27 d on trial, gilts were slaughtered and carcass measurements were recorded at 24 h post-mortem. Overall, RAC supplementation did not affect ADFI or P2 (P > 0.05) but did influence LW (P = 0.049) and overall G:F (P = 0.012) after d27. At d15-d21 and d22-27, only a tendency (P = 0.169, 0.104 respectively) for a linear decrease in G:F with RAC supplementation was found. RAC also affected HCY (P= 0.045) and CCY (P = 0.045) but not fat depth, meat depth or fat % (P > 0.05). These results indicate that RAC may have small but beneficial effects in modern pig production, but further research is required to optimize concentrations and duration of supplementation in modern lean pig genotypes.
Dissertation (MSc (Agric))--University of Pretoria, 2016.
Animal and Wildlife Sciences
MSc (Agric)
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17

Flohr, Joshua Richard. "The effects of various sources and levels of supplemental vitamin D3 on growth performance and serum 25(OH)D3 of young pigs." Thesis, Kansas State University, 2013. http://hdl.handle.net/2097/15196.

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Master of Science
Department of Animal Sciences and Industry
Jim Nelssen
Seven experiments using a total of 3,251 preweaned pigs, nursery pigs, and sows were used to determine the effects of: 1) supplemental vitamin D[subscript]3 on suckling and nursery pig growth, and maternal performance, and 2) high sulfate water, dietary zeolite and humic substance on nursery pig performance. Also, a web-based survey was developed to question pork producers and advisors of the swine industry on their knowledge of feed efficiency. Experiment 1 tested an oral dose of either; none, 40,000 or 80,000 IU vitamin D[subscript]3 given to pigs 24 to 48 h after farrowing. No differences in growth performance or bone mineralization were observed, but vitamin D[subscript]3 supplementation increased serum 25(OH)D[subscript]3 on d 10, 20, and 30, but returned to control values by d 52. Experiments 2 and 3 evaluated an oral dose of vitamin D[subscript]3 to pigs just before weaning, as well as added D[subscript]3 in nursery diets and in drinking water. There were no effects on growth performance; however, serum 25(OH)D[subscript]3 increased with all sources of vitamin D[subscript]3 supplementation. Experiment 4 evaluated if pigs had a preference to 1 of 3 dietary concentrations of vitamin D[subscript]3. Pigs ate less feed from diets containing very high levels of vitamin D[subscript]3 compared to commonly supplemented levels. Experiment 5 evaluated 3 levels of vitamin D[subscript]3 in sow diets. There were no effects on sow productivity, subsequent pig performance, or piglet bone ash content. However, increasing vitamin D[subscript]3 increased sow serum 25(OH)D[subscript]3, milk vitamin D, and pig serum 25(OH)D[subscript]3. Experiment 6 and 7 evaluated the effects of dietary zeolite and humic substances in nursery pigs drinking high sulfate water. Ultimately, pigs drinking high sulfate water had increased fecal moisture content and decreased growth performance, and feed additives evaluated were ineffective in ameliorating these negative effects. Finally, data collected from the feed efficiency survey suggest that there are knowledge gaps about practices that effect feed efficiency. Results from this survey will help extension educators better target specific industry segments with current information and provide more specific areas of future research where lack of information has been identified.
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18

Kunii, Eduardo Miyamoto Fukanoki [UNESP]. "Frequência alimentar e taxa de alimentação para Kinguio criado em hapa: desempenho produtivo e avaliação econômica." Universidade Estadual Paulista (UNESP), 2010. http://hdl.handle.net/11449/96503.

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Made available in DSpace on 2014-06-11T19:28:21Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-07-08Bitstream added on 2014-06-13T18:57:25Z : No. of bitstreams: 1 kunii_emf_me_botfmvz.pdf: 301873 bytes, checksum: 4b8b58dc7e25c2545e98d937d27b4c8b (MD5)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Universidade Estadual Paulista (UNESP)
Com o trabalho, objetivou-se avaliar o desempenho do kinguio (Carassius auratus) em hapas providas com dispensadores automáticos de ração utilizando frequências alimentares de seis, 12 e 24 vezes ao dia e duas taxas de alimentação, 5% e 10% do peso vivo da biomassa, durante 75 dias. As hapas foram instaladas em tanques-rede submersos a um metro de profundidade em um viveiro escavado de 2.000m2. O delineamento experimental foi inteiramente casualizado em esquema fatorial com três frequências alimentares e duas taxas de alimentação. Cada tratamento teve três repetições e os peixes foram alimentados com ração comercial. Foram utilizadas 18 hapas de 0,42m³ onde foram distribuídos 75 peixes com peso médio inicial de 5,26± 1,52 gramas em cada unidade experimental. As frequências alimentares de seis, 12 e 24 vezes ao dia foram semelhantes com a taxa alimentar de 10% (P>0.05). Já com a taxa de 5% o desempenho produtivo foi superior naqueles alimentados de hora em hora em relação aos demais – P<0.05. Como esperado, observou-se maior ganho de peso nos kinguios submetidos à maior taxa de alimentação, apresentando o valor médio de 40,01 gramas, enquanto que na menor taxa o valor foi 32,07g. Em relação à frequência alimentar, os melhores resultados foram obtidos com maior parcelamento da ração. Com o fornecimento de ração de hora em hora o peso médio foi de 38,59g, quando os animais foram alimentados a cada duas horas apresentaram peso médio de 36,89g e quando receberam ração a cada quatro horas o peso médio de 33,75g. A conversão alimentar dos peixes que receberam 5% de seu peso em ração foi de 1,66, sendo que para os peixes que receberam 10% foi de 2,85. As conversões para os animais que foram alimentados a cada quatro horas, a cada duas horas e a cada hora foram 2,01; 2,32 e 2,44, respectivamente...
In the present work the performance of kinguio (Carassius auratus) in hapas with automatic feeder, fed with 5% and 10% level of body weight in frequencies of six, 12 and 24 times a day was studied during 75 days. The hapas of 0.42 m³ was distributed in 18 cages submerged one meter depth in a water reservoir of 2.000m². There were used kinguio with 5.26 ± 1.52g in each experimental unit in a density of 75 fishes/m³. The experimental design used was a completely randomized whit three replicates in outline factorial three frequencies and two level, a commercial ration used. In 10% level the times frequency of six, 12 and 24 times a day were similar (P> 0.05). However the performance was higher with 5% level in those fed hourly over the other - P <0.05. As expected, the higher level of body weight provided greater weight gain in kinguios with the average value of 40.01g, whereas the lowest level the value was 32.07g. The best results were obtained with greater fragmentation of the ration in relation of food frequency. The supply of food in each hour, the average weight was 38.59g, when the animals were fed every two hours the mean weight 36.89g and when fed every four hours the average weight of 33.75g. Fishes that received 5% level of body weight the feed conversion were 1.66, while for the fishes receiving 10% were 2.85. For animals that were fed every four hours every two hours and each hour the feed conversions were 2.01, 2.32 and 2.44, respectively. The increase of frequency of food associated a lower level of body weight improved utilization of the ration resulting in better performance
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19

Morejon, Jacome Aida Esperanza. "Determination of the primary levels of the residues of the seeds of wheat, maize, and barley for the elaboration of the food mixture for rabbits." BYU ScholarsArchive, 2006. https://scholarsarchive.byu.edu/etd/5404.

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The present investigation was done in the parish of Chaltura, Granja "La Pradera" which belongs to the University Técnica del Norte. The main objective of this investigation was to determine the primary levels of the residues of the seeds of wheat, maize, barley for the elaboration of the food mixture for rabbits. The evaluated variables, food consumed, weight gain, food value, protein percentage, production cost per treatment. Previously to the initiation of the field phase bromatological analysis were done on the three food mixtures in the National Institute of Farming Investigation, Quality and Nutrition Area. The treatments were four: TI 13.84% of protein, T2 15.87% of protein, T3 19.57% of protein, T4 (Testigo) 18% of protein The field phase lasted 90 days and 48 rabbits of the New Zealand race were used, 50% males, 50% females each of 45 days old. A randomly design was used with four treatments and six repetitions, also in the different determined significant cases between the used treatments in the Tukey 5% test From the analysis obtained the results were to administer food with a low level of protein, animal consume a major quantity like we can observe in the results of the TI which has 13.84% of protein raising the production costs, while in the major treatment the T2, which has 15.87% of protein, because of its composition it was good tasting for the animals, making the consumption of the food will increase the normal weight, and the cost of production per Kg. Of food is $0.28. The T3 has 19.57% of protein the same which is in excess since the animals only assimilate what they need and the rest is the cost of production per Kg. Of food is $0.28. The T3 has 19.57% of protein the same which is in excess since the animals only assimilate what they need and the rest is waste, besides raising the protein level, this raises the cost of the food mixture. And the commercial food the T4 (Testigo) had reasonable results, in the food consumption of the pellet food mixture like the weight increase, but it is not recommended for farming families for the cost of Kg. $0.40, giving also another alternative like the T2(15.87% of protein) with a cost of Kg. Of $0.28. Besides the experimental mixtures to the animals water was supplied and 150 gr. Of alfalfa in the afternoon on a daily basis. An enabling study was done about the raising of rabbits, and the elaboration of the food mixtures in the various families of the Agualongo, Chimbaloma, Pucará, Peguche, Imbaya, Iluman, Compania, Agato, Calpaqui, Punyaro, Quinchuqui, communities, all belonging to Antonio Ante and Otavalo.
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20

Gutierrez, Jenny Lourdes Mamani. "Evaluation of diets with different levels of barley sprouts (Hordeum vulgare) in the basic feed of guinea pigs (Cavia aperea porcellus) in the phases of growth." BYU ScholarsArchive, 2001. https://scholarsarchive.byu.edu/etd/5375.

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The study was done in the department of La Paz, providence of Ingavi in the community of Letanias (16° 39’ 15” S; 69° 60’ 18” W), in the Benson Institute building, located 3 kilometers from Viacha. The objectives were: to evaluate the growth and increase in weight and consumption of food in Guinea pig male and females under the effect of diets with different levels of barley sprout in the phases of growth; to determine the nutritional conversion; to determine the optimal level of use of the barley sprouts in the basic feeding of Guinea pigs; and to evaluate the results of the diets from the point of view of its economic efficiency. The diets utilized were isoprotein and isoenergetic and consisted of the following: D l (34% H. alfalfa + 33% P. barley + 33% bran), D-2 (45%H. alfalfa + 25% sprout + 14% P. barley + 16% bran), D-3 (35% H. alfalfa + 50% sprout + 12% P. barley + 3% bran), D-4 (22% H. alfalfa + 75% sprout + 2% P. barley + 1% bran). The design that I used was completely random with factorial arrangement, with four repetitions, taking into account 64 animals 32 male and 32 females. I analyzed the variables with the statistical package MSTATC obtaining the following results.- The analysis of variance obtained for the gaining and increasing of weight, I present differences in the phases of evaluation (sixth and eleventh week). Being D-2 the diet that presents greater weight with referring to the diets D l, D-2 and D-3. The consumption of food was greater in the diet D-2, showing greater flexibility than the diets D-2, D-3 and D-l. Analyzing the nutritional conversion index, weight, and economic relation it is concluded that the diet D-2 with 25% of barley sprout is the one that achieves the best behavior, achieving a good use of the goods that farmers have and the cost of feed is attainable for the producer. Barley sprouts can be an alternative feed for the guinea pig always as long as administered in low levels.
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21

Camilo, Danilo de AraÃjo. "Ingestive behavior, performance, carcass characteristics and non-carcass components of Morada Nova lambs fed different levels of metabolizable energy." Universidade Federal do CearÃ, 2011. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=7070.

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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico
The objective of this study was to evaluate the ingestive behavior, average daily weight gain (ADG), feed conversion (FC), feed efficiency (FE), carcass characteristics, commercial cuts weights and yield, weight of gastrointestinal content and compartments, weight and yield of internal organs of Morada Nova growing lambs fed different levels of metabolizable energy (ME). 32 lambs, non-castrated, with average initial body weight of 12.12 Â 1.69 kg and approximately 60 days of age were used. Animals were distributed into four experimental treatments determined by different levels of metabolizable energy (1.28, 1.72, 2.18 and 2.62 Mcal/kg DM), in a randomized block design with eight replicates per treatment. Tifton 85 hay was used as roughage. Lambs were slaughtered sequentially as the group of animals of each treatment reached an average of 25 kg of body weight. Increasing linear effect was observed of metabolizable energy levels (P<0.05) over dry matter (DM) intake and decreasing linear effect for neutral detergent fiber (NDF) intake, both expressed in g/day, %BW e g/kg0,75. Eating, ruminating and total chewing times, expressed in h/day, decreased linearly (P<0.05) with increasing levels of energy in the rations. Idle time, in turn, increased linearly (P<0.05). Eating and rumination efficiencies were influenced by the energy levels (P<0.05) expressed in g DM/h. The number of ruminal boluses, number of chews and chews per ruminal bolus were not affected by the levels of ME. However, time spent chewing per ruminal bolus was influenced (P<0.05). Increased linear effect (P<0.05) was observed for ADG, without affecting, however FC and FE. Carcass traits such as: empty body weight, hot carcass weight and yield, cold carcass weight and yield, loss by cooling and biological yield were not affected (P>0.05) by the increasing levels of dietary energy. Increased linear effect (P<0.05) was also observed for ribeye area and decreased linear effect (P<0.05) for loss by fasting with the increasing of ME levels. The levels of energy also decreased (P<0.05) the weight of the cuts shoulder and leg (%), and increased linearly the neck (kg), rib, breast and flank expressed in kg and%. There was no effect of energy levels (P>0.05) on weight of gastrointestinal content. Increased linear effect (P<0.05) was observed for the weights of heart, the group of organs lungs, trachea, esophagus and tongue (PTEL), liver and spleen, expressed in kg. Regarding the compartments of the gastrointestinal tract, it was observed increased linear effect (P<0.05) only for rumen-reticulum, in %, and small intestine, in kg. The perirenal, omental and mesenteric fats were also influenced by the energy levels (P<0.05) with linear increase when expressed in kg and %. It was concluded that the increase of ME levels of diets influences the ingestive behavior, promote increases in ADG and ribeye area, and reduction in loss by fasting. Regarding the weights of cuts, levels of ME reduce shoulder and leg and increase neck, rib, chest and flank. Levels of ME also influence positively weight and yield of internal organs, viscera and fats of Morada Nova lambs during the growing period.
Objetivou-se com o presente estudo avaliar o comportamento ingestivo de ovinos, ganho de peso mÃdio diÃrio (GMD), conversÃo alimentar (CA), eficiÃncia alimentar (EA), caracterÃsticas de carcaÃa, pesos e rendimento dos cortes comerciais, peso do conteÃdo e dos compartimentos gastrointestinais, peso e rendimento dos ÃrgÃos internos de ovinos Morada Nova em crescimento alimentados com diferentes nÃveis de energia metabolizÃvel (EM). Foram utilizados 32 animais, nÃo-castrados, peso corporal mÃdio de 12,12 Â 1,69 kg e aproximadamente 60 dias de idade. Os animais foram distribuÃdos em quatro tratamentos experimentais determinados por diferentes nÃveis de EM (1,28; 1,72; 2,18 e 2,62 Mcal/kg de MS), em delineamento em blocos casualizados, com oito repetiÃÃes por tratamento. O feno de Tifton 85 foi utilizado como volumoso. Os cordeiros foram abatidos seqÃencialmente, Ã medida que o grupo de animais de cada tratamento atingia a mÃdia de 25 kg de peso vivo. Foi observado efeito linear (P<0,05) crescente dos nÃveis de energia metabolizÃvel sobre consumo de matÃria seca (MS) e decrescente para o consumo de fibra em detergente neutro (FDN), ambos expressos em g/dia, %PV e g/kg0,75. Os tempos de alimentaÃÃo, ruminaÃÃo e mastigaÃÃo total, expressos em h/dia, diminuÃram linearmente (P<0,05) com o aumento dos nÃveis energÃticos das raÃÃes. O tempo de Ãcio, por sua vez, aumentou linearmente (P<0,05). As eficiÃncias de alimentaÃÃo e ruminaÃÃo foram influenciadas pelos nÃveis de energia (P<0,05) expressas em g MS/h. O nÃmero de bolos ruminais, nÃmero de mastigaÃÃes merÃcicas por dia e nÃmero de mastigaÃÃes merÃcicas por bolo ruminal nÃo foram influenciados (P>0,05) pelos nÃveis de EM das raÃÃes. Para o tempo de mastigaÃÃes merÃcicas por bolo ruminal houve efeito significativo (P<0,05). Verificou-se efeito linear crescente (P<0,05) dos nÃveis de EM sobre o GMD sem afetar, no entanto a CA e EA. As caracterÃsticas de carcaÃa: peso de corpo vazio, peso e rendimento de carcaÃa quente, peso e rendimento de carcaÃa fria, perda por resfriamento e rendimento biolÃgico nÃo foram influenciados (P>0,05) pelos aumentos nos nÃveis de energia da dieta. Houve efeito linear crescente dos nÃveis de energia sobre a Ãrea de olho de lombo e perda por jejum (P<0,05). Observou-se ainda efeito linear decrescente dos nÃveis de EM (P<0,05) sobre o peso dos cortes paleta e perna em %, e crescente sobre os pesos de pescoÃo em kg e costela, peito e fraldinha expressos em kg e %. NÃo foi observado efeito (P>0,05) dos nÃveis de energia sobre o peso do conteÃdo gastrointestinal. Verificou-se efeito linear crescente (P<0,05) dos nÃveis de EM sobre os pesos do coraÃÃo, do conjunto de ÃrgÃos: pulmÃes, traquÃia, esÃfago e lÃngua (PTEL), do fÃgado e baÃo, expressos em kg. Em relaÃÃo aos compartimentos do trato gastrointestinal foi observado efeito linear crescente (P<0,05) dos nÃveis de EM somente sobre o rÃmen-retÃculo em %, e intestino delgado em kg. As gorduras perirenal, omental e mesentÃrica tambÃm foram influenciados pelos nÃveis de energia (P<0,05) com incremento linear para os pesos em kg e %. Conclui-se que o aumento dos nÃveis de energia metabolizÃvel da raÃÃo influencia o comportamento ingestivo de ovinos e proporciona aumentos no GMD, Ãrea de olho de lombo, e reduÃÃo na perda por jejum. Em relaÃÃo aos pesos dos cortes comerciais o aumento nos nÃveis de EM reduz o peso de paleta e perna e aumenta os pesos do pescoÃo, costela, peito e fraldinha. O nÃvel de EM das raÃÃes influencia positivamente no peso e rendimento dos ÃrgÃos internos, vÃsceras e gorduras de ovinos Morada Nova em crescimento.
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22

Kunii, Eduardo Miyamoto Fukanoki 1983. "Frequência alimentar e taxa de alimentação para Kinguio criado em hapa : desempenho produtivo e avaliação econômica /." Botucatu : [s.n.], 2010. http://hdl.handle.net/11449/96503.

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Orientador: Claudio Angelo Agostinho
Banca: Margarida Maria Barros
Banca: Luiz Edivaldo Pezzato
Banca: João Batista Kochenborger Fernandes
Resumo: Com o trabalho, objetivou-se avaliar o desempenho do kinguio (Carassius auratus) em hapas providas com dispensadores automáticos de ração utilizando frequências alimentares de seis, 12 e 24 vezes ao dia e duas taxas de alimentação, 5% e 10% do peso vivo da biomassa, durante 75 dias. As hapas foram instaladas em tanques-rede submersos a um metro de profundidade em um viveiro escavado de 2.000m2. O delineamento experimental foi inteiramente casualizado em esquema fatorial com três frequências alimentares e duas taxas de alimentação. Cada tratamento teve três repetições e os peixes foram alimentados com ração comercial. Foram utilizadas 18 hapas de 0,42m³ onde foram distribuídos 75 peixes com peso médio inicial de 5,26± 1,52 gramas em cada unidade experimental. As frequências alimentares de seis, 12 e 24 vezes ao dia foram semelhantes com a taxa alimentar de 10% (P>0.05). Já com a taxa de 5% o desempenho produtivo foi superior naqueles alimentados de hora em hora em relação aos demais - P<0.05. Como esperado, observou-se maior ganho de peso nos kinguios submetidos à maior taxa de alimentação, apresentando o valor médio de 40,01 gramas, enquanto que na menor taxa o valor foi 32,07g. Em relação à frequência alimentar, os melhores resultados foram obtidos com maior parcelamento da ração. Com o fornecimento de ração de hora em hora o peso médio foi de 38,59g, quando os animais foram alimentados a cada duas horas apresentaram peso médio de 36,89g e quando receberam ração a cada quatro horas o peso médio de 33,75g. A conversão alimentar dos peixes que receberam 5% de seu peso em ração foi de 1,66, sendo que para os peixes que receberam 10% foi de 2,85. As conversões para os animais que foram alimentados a cada quatro horas, a cada duas horas e a cada hora foram 2,01; 2,32 e 2,44, respectivamente... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: In the present work the performance of kinguio (Carassius auratus) in hapas with automatic feeder, fed with 5% and 10% level of body weight in frequencies of six, 12 and 24 times a day was studied during 75 days. The hapas of 0.42 m³ was distributed in 18 cages submerged one meter depth in a water reservoir of 2.000m². There were used kinguio with 5.26 ± 1.52g in each experimental unit in a density of 75 fishes/m³. The experimental design used was a completely randomized whit three replicates in outline factorial three frequencies and two level, a commercial ration used. In 10% level the times frequency of six, 12 and 24 times a day were similar (P> 0.05). However the performance was higher with 5% level in those fed hourly over the other - P <0.05. As expected, the higher level of body weight provided greater weight gain in kinguios with the average value of 40.01g, whereas the lowest level the value was 32.07g. The best results were obtained with greater fragmentation of the ration in relation of food frequency. The supply of food in each hour, the average weight was 38.59g, when the animals were fed every two hours the mean weight 36.89g and when fed every four hours the average weight of 33.75g. Fishes that received 5% level of body weight the feed conversion were 1.66, while for the fishes receiving 10% were 2.85. For animals that were fed every four hours every two hours and each hour the feed conversions were 2.01, 2.32 and 2.44, respectively. The increase of frequency of food associated a lower level of body weight improved utilization of the ration resulting in better performance
Mestre
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23

Friggens, Nicolas. "The effects of feed composition and level on lactational performance in rats and dairy cows : a basic approach to feed description." Thesis, University of Edinburgh, 1991. http://hdl.handle.net/1842/32230.

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An investigation into the effects of feed composition on lactational performance was carried out using rats and cows. A graphical representation of the feed as a triangle was used to aid the interpretation of results. The first rat experiment showed that, on high protein feeds, the lactational performance of rats is not depressed when offered feeds of very low carbohydrate content. This was substantiated by the other rat experiments. When carbohydrate in the feed was replaced by fat at low protein content (rat experiment 2) there was a large depression in lactational performance, effectively a cessation of mild production. The interaction between the three feed components protein, carbohydrate and fat was highly significant. The hypothesis that maternal heat production was limiting food intake was advanced. The third rat experiment used feeds whose composition was marginal in relation to lactational success. The feeds also allowed comparison between feeds of constant nutrient:energy ratio. The results of this experiment indicated that there is an extremely abrupt threshold in feed composition for adequate lactation. This effect could not be attributed to any one nutrient:energy ratio. This experiment also showed the importance of maternal body reserves in support of lactation. A model was developed to explore the hypothesis that maternal heat production was limiting performance, however this model failed. An experiment using sheep was conducted in order to permit prediction of the volatile fatty acid proportions arising from a range of feeds. This experiment was designed to allow application of the rat work to dairy cows. A dairy cow trial was conducted to compare different feed types and feeding levels. The results of this trial showed no effect of feed type on lactational performance. A linear relationship between food intake and level of milk production was found. This included an effect of feeding level on rate of decline in milk yield. All these findings are discussed in detail.
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24

Rustas, Bengt-Ove. "Whole-crop cereals for growing cattle effects of maturity stage and chopping on intake and utilisation /." Skara : Dept. of Animal Environment and Health, Swedish University of Agricultural Sciences, 2009. http://epsilon.slu.se/200974.pdf.

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25

Cheng, Zhang. "Use of food waste feeds for culturing low trophic level fish (grass carp, bighead carp and mud carp): persistent toxic substances." HKBU Institutional Repository, 2014. https://repository.hkbu.edu.hk/etd_oa/76.

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This study aimed at using different types of food wastes as major sources of protein to replace the fish meal used in fish feeds to produce quality fish. The major objectives were to (1) investigate the variations of metalloid/metals, polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) in the fish ponds (pond mud and water), and food wastes used as fish feeds; (2) analyze bioaccumulation and biomagnification of pollutants in the food chains; and (3) evaluate the potential health risks of exposure (to these pollutants) via dietary intake of fish fed with food waste feeds. The traditional fish farming model was used to culture low trophic level fish: a filter feeder (bighead, Aristichthys nobilis), a herbivore (grass carp, Ctenopharyngodon idellus) and a bottom feeder (mud carp, Cirrhina molitorella), which are more environmental friendly as they can utilize more solar energy. Furthermore, low-trophic level fish are less susceptible to the accumulation of toxic chemicals. Two types of food wastes (mainly containing cereal (Food Waste A) and meat waste meal (Food Waste B)) were used as the major source of protein to replace the fish meal in fish feed to culture fish. The concentrations of metalloid (arsenic (As)), metals (mercury (Hg), cadmium (Cd), chromium (Cr), lead (Pb), zinc (Zn), copper (Cu) and nickel (Ni)) in water, suspended particulate matter and sediment of the 3 experimental fish ponds located in Sha Tau Kok Organic Farm were monitored (bi-monthly during the first half year and tri-monthly during the second half year) and the results were similar to or lower than those in the commercial fish ponds around the Pearl River Delta (PRD) region. Results of the health risk assessments indicated that human consumption of grass carp (a herbivore) which fed food waste feed pellets would be safer than other fish species (mud carp, bighead carp and largemouth bass). There were no or lower magnifications, and low concentrations of metalloid/metals contained in the ponds indicated that the practice of traditional pond management by draining pond water regularly can provide a better fish pond habitat for birds and other wildlife. Furthermore, the use of food waste instead of fish meal (mainly consisted of contaminated trash fish) further reduced Hg accumulation in the cultured fish. During October 2011 - December 2012, the concentrations of PAHs and OCPs in three experimental fish ponds were monitored (bi-monthly during the first half year and tri-monthly during the second half year). The results were similar to or lower than those obtained in commercial fish ponds around the PRD region. The mean concentrations of .PAHs and .OCPs in sediment and fish collected from the experimental fish ponds during the 2nd half year (May 2012 to December 2012) were significantly higher (p<0.05) than those in the 1st half year (October 2011 to April, 2012). .PAHs and .DDTs in the two species of fish (grass carp and bighead carp) were significantly increased (p<0.05) with time, and PAHs and DDTs in grass carp and bighead carp fed with commercial fish feed pellets (control group) were significantly higher (p<0.05) than the fish fed with food waste pellets (Food Waste A and Food Waste B). Fruit, vegetables, bone meal and meat products were the major sources of PAHs and OCPs contamination for producing Food Waste A and Food Waste B. No significant increases in PAHs and DDTs concentrations with trophic levels were observed in the experimental ponds, showing that PAHs were not biomagnifed in the omnivorous food chains (plankton, grass carp, bighead carp and mud carp). DDTs were lower magnifications than those predatory food chains (plankton, trash fish, and largemouth bass) in farmed ponds. There was a very low cancer risk for PAHs and DDTs exerted on humans via consumption of bighead carp, grass carp and mud carp (fed with food waste and commercial pellets). Furthermore, the use of food waste instead of fish meal (mainly consisted of contaminated trash fish) further reduced accumulation of PAHs and DDTs in the cultured fish.PAHs and DDTs exerted on humans via consumption of bighead carp, grass carp and mud carp (fed with food waste and commercial pellets). Furthermore, the use of food waste instead of fish meal (mainly consisted of contaminated trash fish) further reduced accumulation of PAHs and DDTs in the cultured fish. The present results revealed that recycling of food waste for cultivating low trophic level fish (mainly bighead carp and grass carp) is feasible, which will also ease the disposal pressure of the large volume of food waste, a common problem encountered in densely populated cites such as Hong Kong.
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26

Prathalingam, N. S. "The effects of level of feed intake and diet composition during a winter store period on the subsequent performance and carcass characteristics of beef cattle fed grass." Thesis, University of Aberdeen, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.252130.

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This study investigated the hypothesis that cattle fed to produce a lean carcass during a winter restriction period will subsequently grow faster and remain leaner than fatter steers during the summer, exploiting cheap grazed grass. Three studies were carried out; in the first study steers were restricted at three levels of growth (300, 600 and 900 g/day) during winter and turned out to graze grass during summer. At each level of growth during winter steers were fed on one of two diets aimed at producing steers of either a lean or fat carcass composition. At the end of the winter restriction period differences in lean composition were observed at the 300 and 600 g/day growth rates. Steers were slaughtered when they attained the target slaughter weight at the end of summer; but there was no difference between treatments in meat quality characteristics or fat composition. Liveweight gain during the summer period was inversely correlated to winter liveweight gain. Two further studies were carried out to assess the effect of altering carcass composition during winter, fed to a predicted growth rate of 600g/day to investigate the underlying physiological and endocrinological mechanism regulating the growth characteristics. In the first study at the end of winter steers that were fatter had higher glucose and insulin concentrations. No differences between diet treatments were detected in muscle protein synthesis or breakdown. At the end of the winter in the second experiment there were no differences in carcass composition, metabolite or hormone profiles between treatments. For both studies, at the end of summer, steers on different dietary treatments had similar carcass compositions and metabolic parameters. It was concluded that by altering the diet of steers during a winter restriction period the composition of carcass gain can be manipulated. Since steers altered the deposition of carcass protein and fat during the subsequent summer period at grass resulting in similar body compositions at slaughter it was deduced the that composition of steers at the end of winter remains unimportant. Reductions in beef production costs may be attained by restricting the growth rates during winter when commercial feeds are expensive.
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27

Du, Toit C. J. L. "Effect of type and level of carbohydrate supplementation on intake and digestibility of Atriplex nummularia cv. De Kock by sheep." Pretoria : [s.n.], 2006. http://upetd.up.ac.za/thesis/available/etd-07032007-115048.

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28

Ngomani, Delisile. "Effect of dietary threonine level on productivity and carcass characteristics of Ross 308 broiler chickens." Thesis, University of Limpopo, 2019. http://hdl.handle.net/10386/3052.

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Thesis (M.Sc. (Animal Production)) --University of Limpopo, 2019
Two experiments were conducted to determine the effect of dietary threonine level on production performance and carcass characteristics of Ross 308 broiler chickens. In each experiment the diets were isocaloric and isonitrogenous but with different dietary threonine levels.The first part of the study determined the effect of dietary threonine level on feed intake, growth rate, mortality and carcass characteristics of Ross 308 broiler chickens aged between Day 1-21. A total of 150 unsexed day-old chicks were used in a complete randomized design having 5 treatments (6.4, 7.5, 8, 8.5 and 9g of threonine/kg DM feed), replicated three times and having ten chickens per replicate. The second part of the study determined the effect of dietary threonine level on feed intake, digestibility, growth rate, mortality and carcass characteristics of male Ross 308 broiler chickens aged between Day 22-42. Seventy-five male chickens were used in a complete randomized design having 5 treatments (6.4, 7.5, 8, 8.5 and 9g of threonine/kg DM feed), replicated three times and having five chickens per replicate. A quadratic regression model was used to determine the optimal productivity of the chickens while a General Linear Model (GLM) procedures for the statistical analysis of variance was used to detect dietary treatment effects. Where there were significant differences (P<0.05), Turkey’s honestly significant difference test (HSD) was used for mean separation. The chickens were slaughtered at the ages of 21 and 42 days for Experiments 1 and 2, respectively, following ethical standards as recommended by the University of Limpopo Animal Research Ethics Committee (AREC/12/2017: PG). Two chickens per replicate for both studies were slaughtered for the determination of carcass characteristics (carcass and organ weights, gut organ digesta pH and gastro-intestinal length measurements). Dietary threonine levels used in this experiment affected (P<0.05) feed intake, growth rate, live weight, metabolisable energy (ME) intake, nitrogen retention, feed conversion ratio and gut organ weights and lengths of unsexed Ross 308 broiler chickens aged 21 days. Dietary threonine level did not affect (P>0.05) diet digestibility. Feed conversion ratio, pH of the proventriculus digesta, gut intestine length and caecum length of unsexed broiler chickens were optimized at different dietary threonine levels of 9.6, 8.5, 6.6 and 8.4 g/kg DM, respectively. Dietary threonine levels had an effect (P<0.05) on feed intake, diet digestibility, metabolizable energy, live weight, proventriculus pH values, GIT length, gut organ and carcass organ weights of male Ross 308 broiler chickens between 22 to 42 days of age. Proventriculus and large intestine weights were optimized at different dietary threonine levels of 7.5 and 9.1 g/kg DM feed, respectively. Dietary threonine level did not affect (P>0.05) growth rate, feed conversion ratio of male Ross 308 broiler chickens between 22 to 42 days of age. It is concluded that dietary threonine levels used in this study affected production performance of younger broilers (Day 1-21) more than that of older birds (Day 22-42). However, production variables were optimized at different dietary threonine levels. This has implication on diet formulation for the chickens and no linear response could be established
National Research Foundation (NRF), and the Department of Agriculture, Forestry and Fisheries (DAFF)
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29

Simpson, Sarah Jordan. "Nitrogen Utilization and Performance in Ruminants Fed Oscillating Dietary Protein Levels." Thesis, Virginia Tech, 2000. http://hdl.handle.net/10919/34393.

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Nitrogen excreted by ruminants may negatively impact the environment, and N not retained is not utilized for growth and production. Experiments were conducted to examine the effect of 48 h oscillation of two levels of low ruminally degradable dietary CP on N metabolism in lambs and performance of steers. In Exp. 1, a metabolism trial was conducted with 28 lambs (31 kg), allotted to four different diets: 8% CP, 10% CP, 12% CP, and 8% and 12% CP diets oscillated every 48 h. After adaptation, transition, and preliminary periods, feces and urine were collected for 10 d. Ruminal fluid and blood samples were taken at the end of collection and again 2 d later. In Exp. 2, 24 crossbred steers (228 kg) were allotted to four diets: 1) 7.5% CP, 2) 9% CP, 3) 10.5% CP, and 4) 7.5% and 10.5% CP diets oscillated every 48 h. Feed intake was measured during the 112 d study, and ADG and gain to feed ratio were calculated. Cattle were weighed every 14 d and blood samples were taken every 28 d. In Exp. 1, N retention was lowest (P < 0.05) for the lambs fed the 8% CP diet, with no differences among lambs fed the other diets. Differences in urinary N excretion accounted for most of the differences in total N excretion. Ruminal NH3-N and BUN levels were greater in animals fed higher amounts of CP. Ruminal pH and VFA concentrations were not affected by diet. In Exp. 2, feed intake did not differ among steers fed different diets. Average daily gain was lowest for cattle fed the 7.5% CP diet. No significant difference was evident for ADG between steers fed the 7.5/10.5% CP oscillating diet and those fed the 9% or the 10.5% CP diet. Gain to feed ratio was lower (P < 0.05) for steers fed the 7.5% CP diet compared to steers fed all other diets. Blood urea N level was higher for cattle fed the 10.5% CP diet than those fed the two lower CP levels, and differences were usually significant (P < 0.05). No consistent significant difference in BUN levels existed between steers fed the 7.5/10.5% CP oscillating diet and those fed the 9% and 10.5% CP diets continuously. Oscillating two levels of low ruminally degradable dietary CP every 48 h had no significant effect on N retention in lambs nor on the performance of steers compared to animals fed the same level of CP daily in these experiments.
Master of Science
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30

Gerretsen, Jan Hendrik. "Flood level prediction for regulated rain-fed rivers." Enschede : University of Twente [Host], 2008. http://doc.utwente.nl/60319.

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31

Tomlinson, Dana J. "Effect of varying levels of neutral detergent fiber and total digestible nutrients on dry matter intake of dairy heifers." Thesis, Virginia Tech, 1988. http://hdl.handle.net/10919/43297.

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One hundred and eight Holstein dairy heifers were divided into two weight blocks based on beginning body weight (E = < 182 kg, light, > 270 kg, heavy). Heifers within weight blocks were randomly assigned to one of five treatments. Treatments consisted of three levels of NDF (35%, 45%, 55%) at 100% ofNRC TDN recommendation, and three levels of TDN (85%, 100%, 115 of NRC) at 45% NDF for light heifers. For heavy heifers, treatments consisted of three levels of NDF (40%, 50%, 60%) at 100% NRC TDN, and three treatments with similar levels of TDN at 50% NDF. Heifers were fed total mixed rations of corn silage, alfalfa haylage, ground orchardgrass hay, soybean meal, high moisture corn and a mineral mix formulated for 0.68 kg ADG. Mean gains (kg/d) were 1.07 and .96 for the light and heavy blocks, respectively. DMI as a percent of BWT differed across NDF levels for light heifers (3r'= 2.96, 2.56, 2.57, 2.57, and 2.87 % of BWT for the low, med., high NDF, and low, high TDN treatments, respectively). Heavy heifer DMI% did not differ (.Â¥= 2.45, 2.40, 2.24, 2.15, and 2.42 % ofBWT for low, med., and high NDF, and low, high TDN treatments, respectively). Equations to predict DMI were developed using intake information from this and a previous study. Backward stepwise regression was utilized to generate a simplified model. Model selected was: DMI (kg/d) = -5.9781 + (2.2120E-05 * BWTSQ) - (5.5527 * GAIN) + (2.7837 * GAINSQ) + (0.4668 * NDF) + (5.3930 * NDFSQ) + (0.03285 * DM) + 1 (7.7859E-03 * BWT * GAIN);11 = 514, rz = .67.
Master of Science
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32

Chester-Jones, Hugh. "Physiological effects of feeding high magnesium levels to steers." Diss., Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/54264.

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A 130-d study was conducted with 24 363kg steers allotted to four diets containing .3 (basal), 1.4, 2.5 and 3.7% Mg, dry basis. An attempt was made to feed cattle on all treatments equal amounts of the basal diet, but steers fed the two high levels refused some feed. Grab fecal samples were collected during nine 10-d periods. Chromic oxide was used as a digesta marker. Jugular blood samples were taken on d 1, 5, 10, 20 and every 10 d thereafter. Steers were sacrificed at the end of the study for gross pathological and histological observations and tissue samples were taken for mineral analysis. Severe diarrhea was observed in steers fed the two higher Mg levels. Tubular strands of mucosal tissue were consistently voided in the feces of cattle fed these levels of Mg. Steers fed the two higher Mg levels became more lethargic as the study progressed. Fecal dry matter content and apparent dry matter digestibility decreased linearly (P<.01) with increasing dietary Mg. Weight losses for steers fed 1.4, 2.5, or 4.7% Mg were 5, 27 and 29 kg, respectively, during the study, compared to a weight gain of 9 kg for cattle fed .3% Mg (quadratic effect, P<.01). Apparent absorption of Mg generally increased with dietary Mg (P<.01), except between d 20 and 70 when it decreased (P<.01). Apparent absorption of Ca and P generally decreased with dietary Mg but effects on P absorption were not always significant. Increasing dietary Mg resulted in a linear elevation of serum and erythrocyte Mg (P<.01) and inorganic P (P<.05) and a linear decrease in serum Ca (P<.01). Plasma osmolality tended to be lowest in steers fed the highest dietary Mg. Serum parathyroid hormone was suppressed at the higher Mg intakes at 3 h but not at 9 h after feeding. Ruminal fluid pH increased as dietary Mg increased from .3 to 2.5%, then decreased (quadratic effect, P<.05). A linear increase in pH (P<.05) was recorded with increasing dietary Mg in digesta samples taken at slaughter from the lower ileum and large intestine. The Mg concentration in the liver, kidney, skeletal muscle and rib-bone and the P concentration in the skeletal muscle increased linearly (P<.05) with dietary Mg. Histologically, amorphous crystals were seen in the kidney tubules of all animals. Increasing dietary Mg in the steers caused a progressive degeneration of the rumen papillae epithelium.
Ph. D.
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33

Kohlen, Corinne Rose. "The Effects of Aging on Muscle Loss and Nuclear Factor Kappa-B Levels in Rats Fed a Diet Containing Suboptimal Leucine Levels." DigitalCommons@CalPoly, 2009. https://digitalcommons.calpoly.edu/theses/32.

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Loss of muscle due to aging is often associated with significant detrimental effects. Therefore, it is crucial to understand signaling molecules that may trigger the muscle loss or prevent the process. The transcription factor, Nuclear Factor Kappa-B (NF-κB), is associated with both catabolic and anabolic pathways of muscle metabolism and may be involved in age-related muscle loss. Leucine is an essential amino acid that is required for both protein synthesis and intracellular signaling pathways that regulate protein synthesis and degradation. The current study examined muscle NF-kB levels in male Sprague-Dawley rats, aged 6 (adult) and 21 months (old) fed a diet containing suboptimal leucine levels for 10-17 days. We found that old rats consumed less grams of food per body weight (BW) each day than adult rats (1.45% g diet/g BW vs. 2.4% g diet/g BW). Weight loss during the study was not significantly different between age groups. However the average mass of gastrocnemius and soleus muscles (g muscle/g BW) was significantly lower in old rats. Reduction in gastrocnemius (g muscle/g BW*10²) was associated with 1.8 fold higher muscle cell NF-κB in old vs. adult rats (p = 0.0443). There was also a higher level of ubiquitinated proteins in old gastrocnemius muscle cells relative to the adult gastrocnemius, however differences did not reach statistical significance. For tibialis anterior muscle, the average mass (g muscle/g BW*10²), NF-κB levels and ubiquitinated proteins were not significantly different between adult and old rats. Our findings suggest that aging affects muscle loss and NF-kB in a tissue-specific manner in rats fed a diet with suboptimal leucine levels.
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34

Staniar, William Burton. "Growth of Thoroughbreds fed Different Levels of Protein and Supplemented with Lysine and Threonine." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/35599.

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Currently accepted optimum protein levels for growth in the horse may be reduced with amino acid supplementation. This study investigated the effects on growth and protein status of Thoroughbred foals offered a supplement with a typical CP level to a supplement that had a lower CP level fortified with limiting amino acids. The control supplement (CS) contained 14% CP, 3.0 Mcal/kg DM, 10% corn oil, 22% soybean meal, 1.4% calcium, and three sources of fiber. The experimental supplement (LTS) contained 9% CP, 3.0 Mcal/kg DM, 10% corn oil, 3% soybean meal, 1.4% calcium, three sources of fiber, and was fortified with .6% lysine and .4% threonine. Lysine and threonine are the first two limiting amino acids in common diets of the horse. Mares and foals were fed twice daily (0700 and 1400) and kept on 30-acre pastures (mixed grass/white clover) until weaning (7 months). Weanlings continued on specified supplements and pastures for seven additional months. Physical measurements and blood samples were taken monthly. Measurements included weight, average daily gain (ADG), body condition (BC), wither height, hip height, length, girth, forearm length, front and hind cannon length, physis and fetlock circumference. Blood analysis included total protein (TP), albumin (ALB), creatinine (CREA), and plasma urea nitrogen (PUN). Effect of diet and time were evaluated by analysis of variance with repeated measures. No differences were found in physical measurements between the CS and LTS groups (ADG 0.8(0.4 kg/day, BC 4.9(0.05) for the observational period. Blood data also showed no difference for the period (ALB 2.9 ( 0.03 g/dl, TP 5.7 ( 0.10 g/dl, CREA 1.1 ( 0.02 mg/dl). These results suggest that the foals offered the LTS faired as well or better than foals on the CS. Lower levels of crude protein (CP) in the diet will result in less nitrogen pollution of pasture lands due to better utilization in the horse. By fortifying a low protein diet with the first two limiting amino acids, the protein is used more efficiently for growth and development, thereby benefiting both the horse and the land.
Master of Science
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35

Azevedo, Paula Alexandra Gil. "Effects of feeding level, water temperature and diet composition on growth and efficiency of feed utilization in two salmonids." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ33201.pdf.

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36

Holtshausen, Lucia. "The effect of different levels of protein degradability in starter- and finishing diets on veal calf performance." Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/51967.

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Thesis (MScAgric)--University of Stellenbosch, 2000.
ENGLISH ABSTRACT: Veal production is a specialised form of calf rearing in which calves were traditionally raised on all-liquid diets. The early weaning of calves onto concentrated diets provides an economically viable alternative rearing method with comparable calf performance. The emphasis in meat production has shifted to the production of lean meat, therefore the deposition of protein instead of fat has become a priority. The optimum level of dietary crude protein for growing calves is well established. Very little, however, is known about the influence of protein degradability in the diet of young ruminants. Recommendations by the NRC are derived from data obtained using lactating dairy cows. The aim was to obtain data on which recommendations for the level of degradable protein in starter and finisher diets for calves could be based. Two experiments were conducted to examine the effect of different levels of dietary crude protein degradability in starter and finisher calf diets on veal calf performance. In both experiments Holstein bull calves were 3 - 10 days of age at the onset, weaned at 4 weeks of age and slaughtered at 20 weeks of age for veal. In Experiment 1 calves were randomly assigned to one of three treatments: low (LO), medium (MD) and high (HO) rumen degradable protein. Calves received a starter diet up to 11 weeks of age and finisher diets from week 12 - 20. In Experiment 2 calves received a starter diet either high or low in rumen degradable protein up to 10 weeks of age. In the finishing period (week 11 - 20) both the low and high groups were again divided into a low and high group, resulting effectively in 4 treatments, viz. LL, LH, HL and HH. The diets in both experiments were formulated to be iso-nitrogenous and iso-caloric, differing only in rumen undegradable protein content within periods and. respective experiments. Body weight gain, feed intake and feed conversion efficiency data for the preweaning, starter, finishing and total experimental period was compared between treatments. There were no significant differences for feed intake, body weight gain or feed efficiency in the starter period of both experiments between treatments. In the finishing period of Experiment 1 the average daily gain for the LO treatment was significantly higher than for the HO treatment, with the MD treatment having an intermediate value. The feed conversion ratio (FCR) for the LO treatment was also significantly better than for the other two treatments. In Experiment 2 the FCR tended (P = 0.0984) to differ between treatments in the finishing period. Calves from the LL and HL treatments had a more favourable FCR than calves from the LH treatment. The HH treatment had an intermediate FCR. According to these results crude protein degradability appears to have an effect on the FCR in the finishing period. The lack of response to higher levels of undegradable dietary protein in calves younger than 10 weeks may be due to underdeveloped rumen functions and it seems possible for high degradable protein to escape degradation to a higher extent than at a later age. In a third experiment, Holstein bull calves and Holstein cows were used to determine and compare the dry matter and crude protein degradability of the four calf diets used in Experiment 2. Rumen VFA concentrations, pH level and NH3-N concentrations were measured for the cannulated Holstein calves to evaluate the level of rumen metabolic maturity of growing calves. Five Holstein bull calves were ruminally cannulated at 6 weeks of age. Dry matter and crude protein degradability were determined once weekly from week 8 - 20 by means of 24 h in sacco incubations. Three ruminally cannulated Holstein cows were used to determine the comparable values for mature ruminants. Dry matter and crude protein degradability differed significantly between the low and high degradable diets for both calves and cows. Dry matter and crude protein degradability in calves increased up to 11 and 12 weeks of age respectively, and then appeared to remain constant to week 20. Dry matter and crude protein degradability values of the starter diets were lower for the calves than for the cows, but values were similar for the finisher diets. Rumen VFA concentrations, pH level and NH3-N concentration showed some fluctuation between weeks, but were similar to literature values for mature animals.
AFRIKAANSE OPSOMMING: Titel: Die invloed van verskillende vlakke van proteïendegradeerbaarheid in aanvangs- en afrondingsdiëte op kalfprestasie in 'n kalfsvleisproduksiestelsel. Kalfsvleisproduksie is 'n gespesialiseerde grootmaakstelsel wat tradisioneel alleenlik op vloeistofdiëte gebaseer was. 'n Stelsel waar kalwers vroeg gespeen word en 'n volledige aanvangs- en afrondingsrantsoen ontvang, bied 'n alternatiewe metode wat ekonomies lewensvatbaar is en vergelykbare kalfprestasie tot gevolg het. Die klem in vleisproduksie het verskuif na die produksie van maervleis. Die neerlegging van proteïen in plaas van vet het dus 'n prioriteit geword. Die optimale vlak van dieetproteïen vir groeiende kalwers is deeglik nagevors. Baie min is egter bekend oor die invloed van proteïendegradeerbaarheid in die dieet van jong herkouende diere. Aanbevelings deur die NRC is afkomstig van data verkry van studies met melkproduserende koeie. Die doel was om data te bekom waarop aanbevelings vir die vlak van degradeerbare proteïen in aanvangs- en afrondingsdiëte vir kalwers gegrond kan word. Twee eksperimente is uitgevoer om die invloed van verskillende vlakke van proteïendegradeerbaarheid in aanvangs- en afrondingsdiëte op kalfprestasie in 'n kalfsvleisproduksiestelsel te ondersoek. Holstein bulkalwers was 3 - 10 dae oud met die aanvang van beide eksperimente, is gespeen op 4 weke ouderdom en op 20 weke ouderdom vir kalfsvleis geslag. In Eksperiment 1 is kalwers ewekansig aan een van drie behandelings toegewys: lae (LO), medium (MD) en hoë (HO) rumen degradeerbare proteïen. Kalwers het tot op 11 weke ouderdom aanvangsdiëte ontvang, terwyl afrondingsdiëte vanaf 12 - 20 weke ouderdom aangebied is. In Eksperiment 2 het kalwers tot op 10 weke ouderdom "n dieet wat óf hoog óf laag in rumen degradeerbare proteïen was, ontvang. In die afrondingsperiode (week 11 - 20) is die lae en hoë groepe elk vervolgens in "n lae en hoë groep verdeel wat effektief tot 4 behandelings gelei het, nl. LL, LH, HL en HH. Die diëte in albei eksperimente was geformuleer om iso-nitrogenies en iso-kalories te wees. Slegs die rumen degradeerbare proteïeninhoud het tussen die onderskeie diëte binne "n bepaalde periode en eksperiment verskil. Gewigstoename, voerinname en voeromsettingsdoeltreffendheid vir die voorspeense-, aanvangs-, afrondings- en totale eksperimentele periode is tussen behandelings vergelyk. In beide eksperimente is geen betekenisvolle verskille gedurende die aanvangsperiode waargeneem t.o.v. voerinname, massatoename en voeromsettingsdoeltreffendheid (VOD) nie. In die afrondingsperiode van Eksperiment 1 was die gemiddelde daaglikse massatoename van die LO behandeling betekenisvol hoër as dié van die HO behandeling, terwyl die MD behandeling "n intermediêre waarde gehad het. Die VOD vir die LO behandeling was ook betekenisvol beter as vir die ander twee behandelings. Die VOD in die afrondingsperiode van Eksperiment 2 het geneig (P = 0.0984) om te verskil tussen behandelings en kalwers van die LL en HL behandelings het "n meer gunstige VOD as kalwers van die LH behandeling gehad. Die HH behandeling het "n intermediêre VOD gehad. Volgens die resultate van hierdie eksperimente het proteïendegradeerbaarheid in kalfrantsoene waarskynlik "n invloed op VOD in die afrondingsperiode. Die gebrek aan respons as gevolg van hoër insluitingsvlakke van nie-degradeerbare proteïen in die rantsoen by kalwers jonger as 10 weke kan moontlik toegeskryf word aan onderontwikkelde rumenfunksies. Dit blyk moontlik te wees dat die hoë degradeerbare proteïenfraksie by jonger kalwers rumendegradering in "n hoër mate as op "n latere ouderdom vrygespring het. In "n derde eksperiment is Holstein bulkalwers en Holstein koeie gebruik om die droëmateriaal- en proteïendegradeerbaarheid van die vier diëte wat in Eksperiment 2 gebruik is, te bepaal en te vergelyk. Rumen WS-konsentrasies, pH-vlak en NH3-Nkonsentrasies is vir die kalwers gemeet om die vlak van metaboliese rumen volwassenheid van groeiende kalwers te evalueer. Vyf Holstein kalwers is op 6 weke ouderdom ruminaal gekannuleer. Droëmateriaal- en proteïen-degradeerbaarheid is een maal per week vanaf week 8 - 20 deur middel van 24 h in sacco inkubasies bepaal. Drie rumen-gekannuleerde Holstein koeie is gebruik om die vergelykbare waardes van volwasse herkouers te bepaal. Droëmateriaal- en proteïendegradeerbaarheid het betekenisvol tussen die lae en hoë degradeerbare diëte vir beide die kalwers en koeie verskil. Droëmateriaal- en proteïendegradeerbaarheid by die kalwers het tot op 11 en 12 weke ouderdom, onderskeidelik, verhoog en daarna tot week 20 relatief konstant gebly. Die droëmateriaal- en proteïendegradeerbaarheidswaardes van die aanvangsdiëte was laer vir die kalwers as vir die koeie, maar die waardes vir die afrondingsdiëte was eenders. Rumen WS-konsentrasies, pH-vlak en NH3-N-konsentrasies het In mate van fluktuasie tussen weke getoon, maar was soortgelyk aan literatuurwaardes vir volwasse diere.
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37

Abdukalykova, Saule. "Cellular and humoral immune responses in birds fed different levels of Arginine and vitamin E." Thesis, McGill University, 2007. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=100753.

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The effects of vitamin E (VE) and Arginine (ARG) on humoral and cellular immunity in chickens were investigated in two experiments. The humoral immunity was measured by antibody responses to sheep red blood cells (SRBC) and maternal antibody titers to the infectious bursal disease virus (IBDV), while the cellular immunity was studied using the cutaneous basophil hypersensitivity test to phytogemagglutinin (PHA) and by counting subpopulations of T-lymphocytes. We used two levels of ARG: normal (NARG, 1.2% in feed) and high ARG (HARG, additional 0.3% in drinking water or 1% in feed in experiments 1 and 2, respectively); and three levels of VE were given: 40, 80, and 400 IU/kg feed in experiment 1, and 40, 80, and 200 in experiment 2.
HARG improved the antibody response to SRBC compared with NARG ( P<0.01 for experiment 1 and P<0.013 for experiment 2) 4 days after injection in both experiments. In experiment 1, the VE80 birds maintained higher antibody titers to SRBC (P<0.001) than the VE40 and VE400 birds 4, 8 and 16 d after inoculation. In experiment 2, the antibody titers to SRBC were higher in the VE80 birds compared with the VE200 birds at days 5, 8, and 12 after inoculation (P<0.001). Maternal antibody titers (log10) to the IBDV were higher in the HARG than in the NARG diet in 17-day-old birds (P<0.001) and higher in the VE80 than in the VE40 birds (P<0.001), yet similar to those of the VE200 birds. No interactions were found between ARG and VE.
Naive birds fed HARG exhibited a higher response than NARG birds (P<0.05) to PHA-P at d 17 and to PHA-M at d 41, but, after a second exposure, high ARG levels did not have an effect. Also, in naive birds, the effects of VE were not significant at d 17, but showed an influence after a second exposure in 41-d-old birds.
The percentage of T-helper (Th) and T-cytotoxic (Tc) cells in the blood of 29-d-old birds were not different between ARG levels (P=0.07 and P=0.06, respectively), but Th cells were higher in the VE80 and VE200 birds than in the VE40 birds, and Tc was higher in the VE80 than in the VE40 birds (P=0.02). The B-cell:T-cell ratio was higher in the HARG than the NARG birds (P=0.01) and in the VE40 compared with the VE80 and VE200 birds (P<0.001). Neither ARG nor VE had an effect on the ratio of Th:Tc cells, nor on the percentage of immature T-lymphocytes.
A combination of high levels of ARG and high levels of VE (80 IU/kg of BW) has an important immunomodulation effect on the cellular and humoral immune responses in broiler chickens, improving both maternal antibody titers against the IBDV and antibody titers against SRBC. A combination of ARG and VE increases the proportions of Th and Tc cells, the B-cell:T-cell ratio, and growth performance. The evidence suggests that ARG and VE play complementary and regulatory role on immune response and may enhance the resistance of broilers to infectious diseases.
Key words. Arginine, vitamin E, humoral immunity, cell-mediated immunity, lymphocyte, ELISA.
L'effet de la vitamine E (VE) et l'arginine (ARG) sur les systèmes hummoraireet cellulaire de l'immunité a était évalué chez la volaille dans deux recherches. Lesystème hummoraire de l'immunité a était évalué en utilisant les paramètres tels que laproduction d'anticorps après une injection des globules rouge provenant des moutons(SRBC) et le niveau d'anticorps maternelle après une infection avec les virus causantla maladie 'infectious bursal disease' (lBDV), tandis que les effets sur le systemcellulaire de l'immunité avaient aussi été évalués en utilisant les paramètres comme'cutaneous basophil hypersensitivity test to phytogemagglutinin (PHA)' et endéterminant la concentration des lymphocytes T. Deux concentrations de ARG avaientété utilisées: normale (NARG, 1.2 % de la diète) et une concentration élevée (HARG,additionel 0.3 % dans l'eau ou 1 % dans les diètes); et 3 concentrations de VE: 40, 80et 400 lU/kg dans les diètes dans la première recherche et 40, 80, et 200 lU/kg dans ladeuxième recherche.
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38

Bajracharya, Keshari. "Corn responses to high levels of copper application as copper rich pig manure." Thesis, Virginia Polytechnic Institute and State University, 1987. http://hdl.handle.net/10919/91157.

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The use of copper (Cu) in pig production to stimulate growth and improve feed efficiency is presently being questioned due to the potential environmental hazards associated with the repeated disposal of the resulting Cu rich manure in agricultural land. Results of field experiments conducted on three diverse Virginia soils indicated that the long-term application of Cu as either copper sulfate or Cu rich pig manure, even at high application rates (average application rate for 9 years was 108 metric tons of manure ha⁻¹ year⁻¹ or 32 kg Cu ha⁻¹ year⁻¹), had no adverse effects on corn yields. Copper levels in corn grain and leaf tissue were not increased by the nine annual applications of Cu rich manure or CuSO₄ , except for a slight increase in Cu concentration in corn grain from CuSO₄ application on only one soil. Copper concentrations in all plant tissues were well within normal ranges for all treatments at all sites. Corn grain yields were not decreased by Cu application on any of the three soils.
M.S.
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39

Zylka, Christine A. "Composition and nutrient utilization by sheep of ensiled tall fescue with different levels of endophyte infection." Thesis, Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/52098.

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Low and high endophyte infected stockpiled tall fescue was harvested, chopped and ensiled in 210 liter metal drums, double lined with polyethylene bags. Endophyte infection averaged 4 and 70%, respectively, for the low- and high-endophyte fescue. A metabolism trial was conducted with 24 wethers fed diets consisting of 100% low-endophyte fescue silage, 50% low-endophyte and 50% high-endophyte fescue silage, and 100% high-endophyte fescue silage. Chopped alfalfa hay was used as a control forage. Single samples were analyzed, so statistical treatment of chemical composition was not possible. However, certain numerical differences were recorded. Lignin was higher for the high-endophyte than the low-endophyte fescue. Dry matter, CP, and ash were similar for the fescue silages. The high-endophyte fescue silage was lower in P, Mg, S, K, Fe, Cu, Mn, Zn, and Al than the low-endophyte silage. Digestibilities of DM, NDF, and cellulose were higher (P<.01) for fescue silages than alfalfa hay. Level of endophyte infection did not affect digestibility of DM, NDF or cellulose. Among silage treatments, apparent absorption of N, expressed as g/d, showed a linear effect (P<.05), with the lowest value obtained for sheep fed 100% high-endophyte fescue silage. Apparent absorption and retention of Ca were higher for silages than alfalfa. Among the silage diets, apparent absorption of P decreased linearly (P<.01) with increased endophyte level. Apparent absorption of K decreased linearly (P<.01) with increased endophyte level, but the effect was related to intake. Serum prolactin concentrations of the wethers fed fescue silage showed a linear decrease (P<.05) with increased proportion of endophyte-infected fescue. Endophyte infection of fescue appears to affect N and mineral metabolism.
Master of Science
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40

Engku, Ariff E. A. R. B. "Space vector Pwm techniques for six-phase three-level inverter-fed drives." Thesis, Liverpool John Moores University, 2018. http://researchonline.ljmu.ac.uk/7982/.

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In recent years, research in the area of multiphase drives has increased significantly. Having higher number of machine phases allows the current to be shared between the phases, thus reducing the current rating of power semiconductors used in the power converter. Additionally, if a multilevel inverter is used to drive the machine, the output voltage waveforms are going to be approximated closer toward sinusoidal waveforms, thus resulting in lower total harmonic distortion. Therefore, the combination of multiphase and multilevel technologies gives considerable benefits compared to conventional two-level three-phase drives. Unlike a carrier-based approach, which can be easily expanded to any number of converter voltage levels and any number of machine phases, the development of space vector algorithms is also reliant on the machine’s configuration. In other words, different drive topologies require their own unique space vector algorithms. In fact, the complexity of developing a space vector algorithm will dramatically increase with the increase of number of levels and/or number of phases. This thesis presents pulse width modulation techniques for two- and three-level asymmetrical and symmetrical six-phase drives with a single or two isolated neutral points configuration. However, since the modulation techniques for the drives with two isolated neutral points are based on the well-established modulation techniques for three-phase drives, more emphasis is given towards the development of modulation techniques for single neutral point case, particularly those that are based on space vector algorithm principles. In order to realise sinusoidal output phase voltage waveforms, several requirements and conditions have to be met. The requirements revolve around ensuring that the low order harmonics, which contribute to the machine losses, will not exist. Meanwhile, the conditions are more towards minimising the switching losses. All modulation techniques are verified through simulation, while those for three-level case are validated experimentally as well. Comparison and discussion of obtained simulation and experimental results, performance and complexity in terms of execution time of the developed modulation techniques, are presented. The equivalence between corresponding modulation techniques, which are based on the space vector algorithm and carrier-based approach are also established.
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Ragnarsson, Sveinn. "Digestibility and metabolism in icelandic horses fed forage-only diets /." Uppsala : Department of Animal Nutrition and Management, Swedish University of Agricultural Sciences, 2009. http://epsilon.slu.se/200992.pdf.

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42

Konopinski, Ryan. "Voltage security assessment with high penetration levels of utility-scale doubly fed induction generator wind plants." [Ames, Iowa : Iowa State University], 2009.

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43

Lee, Hyung-Suk. "Physiological Effects of Chitosan and ChitoRichTM on Rats Fed at Two Levels of Lipid and Fiber." DigitalCommons@USU, 1997. https://digitalcommons.usu.edu/etd/5447.

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Chitin is a polysaccharide derived from the shell of crustaceans. Chitosan is a deacylated chitin derivative and ChitoRich™ is a chitosan-based formulation. Chitosan is known to inhibit dietary fat absorption. ChitoRich™ and chitosan were evaluated for their ability to control fat absorption in growing rats. Forty-eight rats (about 150 g) were fed for 4 weeks on 12 different diets containing two levels of vegetable shortening (15 and 5%) and fiber (5 and 2.5%) with cellulose, chitosan, or ChitoRich™ as the dietary fiber sources. Rats fed ChitoRich™ ate less and gained less body weight than rats fed the other fiber sources. Rats fed ChitoRich™ adapted over time; thus, the weight control effect was not significant during the third and fourth weeks. Feed efficiency of the rats fed ChitoRich™ was lower than that seen in rats fed the other fibers, indicating that calories from a higher percent of absorbed macronutrients were required to maintain their bodies. Apparent fat digest (AFD) was lower in rats fed the ChitoRich™ than in the rats fed cellulose. The reduction of AFD was not as great as that seen by other researchers, possibly due to the low solubility and high viscosity of shortening, compared to corn oil. AFD of the rats fed ChitoRich™ increased over time, suggesting an adaptation to ChitoRich&trad;. Apparent protein digestibility (APD), apparent Ca digestibility (ACaD), and weight gain per unit of protein intake were less in the rats fed ChitoRich™ than in the other fiber-fed groups. ChitoRich™-fed rats had retarded body weight gain, reduced levels of serum albumin, total liver lipids, and epididymal fat weight when compared to the other fiber groups, possibly due to the reduced caloric intake, FD, and APD. Serum cholesterol level was not affected by the fiber source. Liver iron and zinc concentrations were not different among fiber sources, indicating that chitosan and ChitoRich™ may not inhibit the absorption of trace minerals. Liver retinol concentration in the ChitoRich™-fed rats was higher than in the cellulose- or chitosan-fed groups, possibly due to the antioxidant effect of ascorbic acid. All rats were free of microscopic lesions, suggesting that chitosan and ChitoRich™ are safe sources of dietary fiber under these dietary conditions. ChitoRich™ is effective for reducing dietary fat absorption and body weight gain.
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Lyberg, Karin. "Phosphorus in pig diets : effect of liquid feeding, phosphorus levels and phytase supplementation on digestibility and performance /." Uppsala : Department of Animal Nutrition and Management, Swedish University of Agricultural Sciences, 2006. http://epsilon.slu.se/200613.pdf.

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45

Selaledi, Lesego Gaborone Amos. "The influence of different energy, lysine and methionine levels on layer performance." Thesis, Stellenbosch : Stellenbosch University, 2002. http://hdl.handle.net/10019.1/53128.

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Assignment (MPhil)--University of Stellenbosch, 2002.
ENGLISH ABSTRACT: The study conducted was aiming on evaluating the influence of different levels of energy and amino acids, mainly lysine and methionine, on production performance of the layer bird. There were three treatments, namely the Control diet, a high energy, lysine and methionine diet (High spec.) and a low energy, lysine and methionine diet (Low spec.). The energy levels were 11.2 MJ/kg, 11.5 MJ/kg and 10.9 MJ/kg respectively. Lysine levels were 0.67%, 0.73% and 0.63% whereas methionine levels were 0.36%, 0.38% and 0.34% respectively. The experimental design was 3 x 4 factorial, which is 3 treatments with 4 replicates each. Results showed no significant difference (P>0.05) between treatments in egg production, egg mass, egg output, bodyweight and mortality. Feed intakes of the High spec. diet were significantly lower (P<0.05) than that of the control diet and the Low spec. diet.
AFRIKAANSE OPSOMMING: Hierdie studiestuk handeloor die evaluering van die invloed wat die verskillende vlakke van die energie en aminosure, veraiiisien en methionine op die produksie van 'n lê hoender het. Daar was gebruik gemaak van drie behandelings, naamlik die kontrole dieet, 'n hoë energie, lisien en methionien dieet (Hoë spesifikasie), en 'n lae energie, lisien en methionien dieet (Lae spesifikasie). Die energievlakke was 11.2 MJ/kg, 11.5 MJ/kg en 10.9 MJ/kg onderskeidelik. Lisienvlakke was 0.67%, 0.73% en 0.63% waarby methionienvlakke was 0.36%, 0.38% and 0.34% onderskeidelik. Die eksperimentele ontwerp was 3 x 4 fakulteitsfunksies: 3 behandelings met 4 replikas elk. Die resultate het geen noemenswaardige verskille (P>0.05) tussen die behandelinge in eierproduksie, eiergewig, eier-uitset, liggaamsgewig en mortaliteite nie. Die voerinnames van die hoë spesifikasie dieet was aansienlik laer (P<0.05) as die van die kontrole en lae spesifikasie dieet.
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46

Len, Ninh Thi. "Evaluation of fibrous feeds for growing pigs in Vietnam : effects of fibre level and breed /." Uppsala : Dept. of Animal Nutrition and Management, Swedish University of Agricultural Sciences, 2008. http://epsilon.slu.se/200822.pdf.

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47

Chipa, MJ, FK Siebrits, MM Ratsaka, KJ Leeuw, and BD Nkosi. "Growth performance of feedlot weaners cattle fed diet containing different levels of cold press soya bean oilcake." South African Journal of Animal Science, 2010. http://encore.tut.ac.za/iii/cpro/DigitalItemViewPage.external?sp=1001200.

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Abstract The value of cold press soya bean oil cake (CPSBOC) as the source of protein in beef cattle was evaluated. CPSBOC was included in the diets of beef weaners at different levels i.e. 0%, 6%, 13% and 20%. The control diet contained cotton seed oil cake (CSOC) as a protein source. The diets were formulated to be isonitrogenous. A total of 40 weaners (20 heifers and 20 steers) at an average weight of 192.3 ± 20 kg were used. The experiment was a randomized block design with ten replicates per treatment and was conducted over 98 days. The group mass of the steers (700 ± 7.80 kg) was significantly heavier when compared with the heifers (6480 ± 7.80 kg). The average daily gain (ADG) (1.5 ± 2.72) and feed conversion ratio (FCR) (5.5 ± 0.051) of the steers was significantly better than the heifers (1.35 ± 2.72 and 5.7 ± 0.051, respectively) while the steers consume more feed (8.2 ± 14.4 kg) per day as compared to the 7.4 ± 14.4 kg consumed by heifers. The weaners that were fed the diet containing 6% and 13% inclusion of CPSBOC grew significantly better than the other treatments. According to this study, an inclusion level of CPSBOC of between 6 and 13% will yield suitable growth in feedlot cattle. More research is needed to determine the optimum inclusion level of CPSBOC.
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48

Souza, Vinícius Carneiro de. "Protein metabolism and urea kinetic in feedlot Nellore steers fed with different protein sources and inclusion levels /." Jaboticabal, 2020. http://hdl.handle.net/11449/192564.

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Orientador: Telma Teresinha Berchielli
Abstract: The use of rumen undegradable protein (RUP) sources in high-energy diets may be an alternative to increase the nitrogen use efficiency (NUE) in ruminants. In this study we had two main objectives: 1) to understand how the protein content of the diet and the rumen degradable protein (RDP) intake can affect urea recycling and its utilization. 2) how the protein content of the diet and the amino acid profile of the metabolizable protein (MP) can affect the efficiency of the use of amino acids (AA) in feedlot Nellore cattle receiving high-energy density diets. Thus, we evaluated the effects of different sources and protein levels in the diet of feedlot Nellore cattle receiving high-concentrate diets. We had two major hypotheses: 1) reducing dietary N associated with RUP sources can increase NUE by reducing ruminal NH3 concentration, urea production in the liver and urinary N excretion, while maintaining N available for microbial protein (MICP) synthesis through urea N recycling. 2) differences in AA use efficiency exists and the gross AA use efficiency is affected by dietary factors such as N sources and levels. These hypotheses were tested using six Nellore steers, cannulated in the rumen, duodenum and ileum with initial body weight (BW) of 354 ± 11.8 kg and 18 months of age. The animals were randomly assigned to receive each diet once over the 6 periods in a 6 × 6 Latin square design. Experimental diets consisted of 80% concentrate and 20% roughage (DM basis), where fresh chopp... (Complete abstract click electronic access below)
Resumo: O uso de fontes de proteína não degradável no rúmen (PNDR) em dietas de alta energia pode ser uma alternativa para aumentar a eficiência do uso de nitrogênio (ENU) em ruminantes. Neste estudo, tivemos dois objetivos principais: 1) compreender como o teor de proteína da dieta e a ingestão de proteína degradável no rúmen (PDR) podem afetar a reciclagem de uréia e sua utilização. 2) como o teor de proteína da dieta e o perfil de aminoácidos da proteína metabolizável (MP) podem afetar a eficiência do uso de aminoácidos (AA) em bovinos Nelore em confinamento recebendo dietas de alta densidade energética. Assim, avaliamos os efeitos de diferentes fontes e níveis proteína na dieta de bovinos Nelore confinados que recebendo dietas de alto concentrado. Tivemos duas hipóteses principais: 1) reduzir o teor de N na dieta associado às fontes de PNDR pode aumentar a ENU por uma redução na concentração de NH3 ruminal, produção de uréia no fígado e excreção urinária de N, enquanto mantém o N disponível para a síntese de proteína microbiana (MICP) através da reciclagem de ureia. 2) existem diferenças na eficiência do uso de AA e a eficiência bruta de uso de AA é afetada por fatores dietéticos, como fontes e níveis de N. Essas hipóteses foram testadas utilizando seis novilhos Nelore, canulados no rúmen, duodeno e íleo com peso corporal inicial (PC) de 354 ± 11,8 kg e 18 meses de idade. Os animais foram distribuídos aleatoriamente para receber cada dieta por uma vez ao longo dos 6 períodos, em ... (Resumo completo, clicar acesso eletrônico abaixo)
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49

McMeeking, Kevin Paul. "An empirical analysis of the level and changes of UK audit and non audit service fees." Thesis, Lancaster University, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.369492.

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50

Santarosa, Julieta. "Desempenho de pintos oriundos de ovos leves e pesados alimentados com diferentes tipos de ração pré-inicial." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/11/11139/tde-20042010-081258/.

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Dois experimentos foram conduzidos de forma semelhante, variando apenas a idade do lote de matrizes Ross que originou os ovos (42 e 60 semanas de idade, respectivamente, para os experimentos 1 e 2), com o objetivo de avaliar o desempenho de pintos oriundos de ovos leves e pesados, alimentados com dietas pré-iniciais de diferentes formas físicas e níveis nutricionais.. Foram incubados ovos apresentando peso médio de 59,0 e 70,8 g, respectivamente, para o experimento 1 (tendo originado pintos de 41,0 e 49,0g de peso médio) e 66,9 e 75,1g (tendo originado pintos de 46,2 e 52,1g de peso médio), respectivamente, para o experimento 2. Uma parte destes ovos teve o peso de seus componentes determinado. À eclosão, 288 pintos, metade de cada categoria de peso de ovo, foram distribuídos em um delineamento inteiramente casualizado, em 48 parcelas. Cada parcela alojou seis pintos, metade de cada sexo. Os tratamentos experimentais obedeceram a esquema fatorial 2x3 (2 pesos de ovos x 3 tipos de rações préiniciais). Utilizaram-se três dietas de formulação comercial na fase pré-inicial: ração peletizada, com menor nível energético (2.900 kcal/kg), protéico e de aminoácidos, considerada uma dieta de baixos níveis nutricionais (PBN); ração farelada, de mesma composição nutricional da ração peletizada (FBN); ração farelada, com maior nível energético (2.950 kcal/kg), protéico e de aminoácidos, considerada uma dieta de altos níveis nutricionais (FAN). Foram avaliados o tempo de consumo das dietas pré-iniciais e, aos sete e 14 dias, o ganho de peso, o peso vivo, o consumo de ração e a conversão alimentar. Do término das rações pré-iniciais até os 14 dias de idade, as aves receberam uma mesma ração farelada. Em ambos os experimentos o albúmen foi mais pesado nos ovos classificados como pesados (P<0,05). No experimento 1, a dieta PBN foi consumida mais rapidamente por pintos oriundos de ovos pesados. Aos sete dias, a dieta PBN melhorou o peso vivo, o ganho de peso e a conversão alimentar (P<0,05). Já o peso do ovo influenciou o peso vivo, que foi maior para os pintos oriundos de ovos pesados (P<0,05). O benefício da dieta PBN quanto à conversão alimentar, se manteve aos 14 dias, e o peso vivo dos pintos oriundos de ovos pesados que receberam a dieta PBN foi maior do que aqueles que receberam as dietas FBN e FAN (P<0,05). No experimento 2, não houve diferença significativa para o tempo de consumo das dietas pré-iniciais (P>0,05). Aos sete dias, as dietas PBN e FAN proporcionaram aos pintos melhor conversão alimentar (P<0,05). Porém, aos 14 dias, não houve diferença significativa entre as variáveis (P>0,05). Concluiu-se que, em ovos de matrizes de mesma idade, a diferença no peso dos ovos deve-se ao incremento de albúmen. Quanto ao desempenho, os pintos oriundos de matrizes de idade intermediária foram mais influenciados pelas diferenças de peso dos ovos e composições das dietas, sendo que a dieta peletizada beneficiou o desempenho dos mesmos, mesmo apresentando menor nível nutricional.
Two experiments were conducted to evaluate different pre-starter diets on performance of chickens from light and heavy eggs hatched from Ross breeders of different ages. In the experiment 1, these eggs, that showed weight of 59,0 and 70,8g, were hatched from breeders of 42 weeks of age. In the experiment 2, these eggs, that showed 66,9 and 75,1g, were hatched from breeders of 60 weeks of age. The eggs percentage composition was evaluated. After hatching, 288 day-old chicks, males and females, were weight and allocated in 48 cages. In the experiment 1, their live weight was 41,0 and 49,0g; in the experiment 2, 46,2 e 52,1g. The performance trials were conducted in a completely randomized design with 6 treatments and 8 replicates, and the treatments consisted of a 2 3 factorial arrangement of egg weight (light and heavy) and three types of the pre-starter feed. The pre-starter diets used were: micro-pelleted diet, with 2900 kcal/kg and low levels of protein and amino acids (P); mash diet, with the same composition (M1); and mash diet, with 2950 kcal/kg and high protein. This feed was provided at a fixed amount of 200 g per chick and, after that, the birds in all treatments were fed a common starter diet in mash form, until 14 days of age. Live weight, weight gain, feed intake and feed conversion were evaluated on a pen basis. The time required for total consumption of the pre-starter feeds was monitored. In both experiments, the albumen was heavier than the other components. In experiment 1, there was influence of the egg weight only in the first week (P<0,05). At seven days, P diet improved the live weight, weight gain and feed conversion (P<0,05). At 14 days, P diet also improved feed conversion, as well the live weight of chicks from heavy eggs. In the same experiment, heavy chicks consumed 200 g of P diet faster than light chicks. In the experiment 2, the time of intake was not different among treatments (P>0,05). There was not influence of egg weight, but there was influence of P and F2 diets in the first week, that improved the feed conversion. However, this influence did not remain to 14 days (P>0,05). It was concluded that albumen is the heaviest component of egg, inside the same age of breeders. It was also concluded that the chicks from breeders of 42 weeks of age were more influenced by different pre-starter diet composition and egg weight than the chicks from breeders of 60 weeks of age. Although P diet showed lower nutritional level, it improved the performance of chicks from breeders of 42 weeks of age.
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