Literatura académica sobre el tema "Sheep – Feeds"
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Artículos de revistas sobre el tema "Sheep – Feeds"
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Smolders, E. A. A., A. Steg y V. A. Hindle. "Organic matter digestibility in horses and its prediction." Netherlands Journal of Agricultural Science 38, n.º 3B (1 de septiembre de 1990): 435–47. http://dx.doi.org/10.18174/njas.v38i3b.16569.
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Organic matter (OM) digestibility of 53 feeds was estimated in horses, sheep and in vitro using rumen fluid. Feeds tested were: roughages (grass hay, fresh grass, wilted grass silage, forage maize and artificially dried roughage), compound feeds and compound feed ingredients including cereals. Technical merits of the chosen procedure for digestibility trials with horses are discussed. Horse digestibility data for forages were consistently lower than sheep data, with a variable fibre level effect. For compound feeds and compound feed ingredients horse digestibility was about comparable to sheep digestibility allowing for considerable differences between feeds. In vitro digestibility gave a reliable estimation of OM digestibility in horses for the different group of feeds. (Abstract retrieved from CAB Abstracts by CABI’s permission)
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Cooper, S. D. B., I. Kyrizakis y J. V. Nolan. "Diet selection in sheep: The role of the rumen environment in the selection of a diet from two feeds that differ in their energy density". British Journal of Nutrition 74, n.º 1 (julio de 1995): 39–54. http://dx.doi.org/10.1079/bjn19950105.
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The effect of the energy density (ED) of feeds offered as a choice on the diet selection of sheep, and the relationship between the rumen environment and the diet selected from feeds of different ED were investigated in two experiments. In the first experiment two feeds, L and H, and their mixture M (3:1 w/w) were formulated. All feeds had similar calculated metabolizable protein: metabolizable energy (ME) ratios, but differed in ED (7·4, 8·1 and 10·1 MJ ME$sol;kg fresh feed for L, M and H respectively). The feeds were offered ad lib. either singly or in paired choices (L/M, L/H and M/H; n6 per treatment) to growing sheep. Although the rate of live-weight (Lwt) gain on feed H was higher than on feeds L or M, and the daily rate of feed intake lower, the sheep on feed choices did not consume only feed H. Instead they selected a mixture of both feeds offered, such that the total amount of H consumed per kg fresh feed was similar on choices L/H and M/H. The rate of Lwt gain of sheep on choices L/H and M/H was not different from that achieved on feed H alone. In the second experiment the choice L/H was offered to fistulated sheep (10 months of age, mean Lwt 57·5 kg) in an 8×8 Latin square, with 7 d periods. Treatments were infusions into the rumen (total volume 1 litre) over 4 h on days 1–4 of each period of acid (HC1; Acid 1, 400; Acid 2, 300 and Acid 3, 200 mmol/l), alkali (NaOH; Alk 1, 316; Alk 2, 212 and Alk 3, 109 mmol/l) and control (NaCl; Con 1, 315 and Con 2, 209 mmol/l). Infusate osmolalities (mOs/kg) were 795 (Acid 1), 585 (Acid 2, Alk 1 and Con 1), 390 (Acid 3, Alk 2 and Con 2) and 200 (Alk 3). Infusion treatment significantly affected the diet selection of the sheep (P < 0·05) according to the osmolality of infusate, but not according to rumen pH. During infusions intake of feed H tended to decline with increasing treatment osmolality, whereas intake of L remained constant. The effects on diet selection and feed intake were of a short duration with no carry-over effects. These results show that sheep given a choice between two feeds of different ED select a substantial quantity of the low-ED feed; this diet selection is affected by short-term manipulations of their rumen environment, in a manner that is consistent with the maintenance of effective rumen conditions.
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Chaudhry, Abdul Shakoor y Ruba A. I. Mohamed. "Using fistulated sheep to compare in sacco and in vitro rumen degradation of selected feeds". Animal Production Science 51, n.º 11 (2011): 1015. http://dx.doi.org/10.1071/an10273.
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Despite its beneficial role in almost all feed evaluation systems, the in sacco method is inconsistent and labour intensive in estimating the degradation of ruminant feeds. This study compared a rumen fluid-based in vitro method with the in sacco method to estimate degradation of 12 feeds comprising six concentrates and six grasses representing three fields during two seasons of winter and spring. Three feed groups (n = 4) were formed by using two grasses (one per season) and two concentrates. These feeds were incubated alongside blanks, in duplicate, for various hours either in sacco in three fistulated sheep or in vitro by using rumen fluid from the same sheep over three periods using two separate 3 × 3 Latin square designs. The in sacco and in vitro data were statistically compared for the effects of sheep, feed group and period on degradation at each incubation time within each method. The degradation data were fitted exponentially to derive water soluble (a), insoluble (b) and degradation rate (c) constants to estimate effective degradability at rumen outflow rate of 0.02 (P0.02) for each feed in each method. These values were statistically compared for variations within and between feed types for each method. The sheep, group and period did not differ significantly (P > 0.05) for feed degradation at most incubation times within any of these two methods. The in vitro method was able to mimic the in sacco degradation of feeds, although the absolute in vitro values were always lower than the in sacco values. The higher in sacco degradation for almost all feeds were partly attributed to the much greater losses of these feeds during their washing with water at 0 h. The in vitro method did identify significant differences (P < 0.05) in dry matter or crude protein degradations between and within different concentrates and grasses in parallel to the in sacco method. The ranking of feeds was comparable for these methods. The in vitro method can be used in parallel to the in sacco method to estimate degradation of various feeds. However, there is a need for coordinated studies to improve the prediction ability of the in vitro method for its adoption to routinely estimate the degradation of ruminant feeds.
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Kyriazakis, I. y J. D. Oldham. "Diet selection in sheep: the ability of growing lambs to select a diet that meets their crude protein (nitrogen × 6.25) requirements". British Journal of Nutrition 69, n.º 3 (mayo de 1993): 617–29. http://dx.doi.org/10.1079/bjn19930064.
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To test the proposition that sheep are able to select a diet that meets their crude protein (N × 6.25; CP) requirements, feeds L, A, B, C and H with the same energy content (11 MJ metabolizable energy/kg feed) but different CP contents (78, 109, 141, 172 and 235 g CP/kg fresh feed respectively) were formulated. In addition, feed U, which was feed L plus 21.4 g urea/kg (CP content 132 g/kg), was also made. The feeds were offered ad lib. either singly (n 4 per treatment) or as a choice between feed H and another feed (pairs LH, AH, BH, CH and UH; n 9 per feed pair) to individually penned Suffolk × Scottish mule wether lambs, over the live-weight range 25–45 kg. On the single feeds the rates of live-weight gain were 273, 326, 412, 418, 396 and 407 g/day (SE of difference (SED) 34; P < 0.01) and protein (excluding wool) gain were 27, 32, 44, 45, 41 and 39 g/d (SED 4; P < 0.001) for feeds L, A, B, C, H and U respectively. When sheep were given a choice between a feed below (L or A) and a feed above their CP requirements (H; as judged by the single-feeding treatments) the CP concentration selected was not different between the two pairs: 131 (SE 4) v. 133 (SE 4) g CP/kg feed for pairs LH and AH respectively. On the choices BH and CH (a choice between two feeds above requirements) the feed lower in CP was constantly preferred (874 (SE 33) and 910 (SE 33) g feed B and C respectively per kg total feed intake; CP selected was 157 and 178 g CP/kg respectively). However, this was not the case with the UH choice on which sheep consumed only 599 (SE 61) g feed U/kg total feed intake, resulting in a selection of a higher CP in their diet (173 g CP/kg). The live-weight gains of the animals given a choice between two feeds were 416, 387, 415, 410 and 383 g/d (SED 37) and protein gains were 45, 40, 46, 50 and 43 (SE 7) for pairs LH, AH, BH, CH and UH respectively, which were comparable with the best performance achieved on a single feed. The results suggest that sheep were able to select a diet that meets their CP requirements and avoid, at least to a certain extent, excess of protein intake. It is also possible that sheep discriminate against a property of feed U, such as an excess of urea, when this feed is paired with a feed high in CP.
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Pedernera, Mariana, Alejandra Vulliez y Juan J. Villalba. "PSV-23 The influence of prior experience on dietary diversity in sheep". Journal of Animal Science 98, Supplement_4 (3 de noviembre de 2020): 217–18. http://dx.doi.org/10.1093/jas/skaa278.401.
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Abstract The objective of this study was to explore the influence of prior dietary experiences on intake and selection of novel feeds by lambs. Twenty lambs housed in individual pens were assigned to two groups (10lambs/group): Negative (NE) and Positive (PE) Experiences, in a split-plot design. Lambs were offered a nutritive novel feed followed by intra-ruminal infusions of lithium chloride-LiCl (150 mg/kg BW), a toxicant that causes food aversions (NE), or vehicle (water; PE). The feed was offered daily and infusions were delivered only when intake was ≥50g, when the protocol was repeated with another novel feed until 4 feeds (oats, wheat bran, corn, beep pulp) were offered. After exposure, all lambs were tested for their acceptance of single novel feeds, each offered during 2 consecutive days: sorghum grain, rice bran, Calfmanna® pellets and soybean meal. Subsequently, all lambs were offered a 5-way choice among these feeds and alfalfa (familiar feed). Intake data, preference and Shannon’s diversity index (5-way choices) were analyzed with a Mann-Whiney U test. During exposure, the NE group ate less of the 4 feeds than the PE group (P < 0.05). Moreover, as exposure progressed, it took more days for NE lambs to reach the 50 g intake threshold, suggesting that neophobia in this group increased with negative experiences. During testing, NE lambs ate less (P < 0.05) of the novel feeds, except soybean meal, than the PE lambs. During the 5-way-choice test, preference for alfalfa was 63.6±3.5% for NE and 45.2±2.6% for PE (P < 0.001). The Shannon’s index was 0.85±0.05 for NE and 1.24±0.03 for PE (P < 0.001), suggesting that lambs in NE selected a less diverse diet. Thus, prior experience influenced neophobia and dietary diversity, an outcome that could impact the nutrition and welfare of grazing animals introduced to novel environments and the diversity of plant communities.
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Lawrence, K. "Use of monensin sodium in sheep feeds". Veterinary Record 133, n.º 20 (13 de noviembre de 1993): 508. http://dx.doi.org/10.1136/vr.133.20.508.
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Odoi, F. N. A. y E. Owen. "Offering barley straw to lambs near weaning as a means of increasing their subsequent readiness to eat straw". Proceedings of the British Society of Animal Production (1972) 1992 (marzo de 1992): 169. http://dx.doi.org/10.1017/s0308229600022790.
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Sheep housed after grazing and offered straw as a feed show reluctance to eat for several days. Evidence exists to indicate that eating habits can be manipulated through a learning process, especially if manipulation occurs pre-weaning. Australian research by Arnold and Mailer (1977) with unpalatable pastures, and Green, Elwin, Mottershead, Keogh and Lynch (1984) with whole cereal grain, showed that sheep exposed to these feeds early in life were more willing to accept the feeds later in life than others not exposed.The present experiment investigated whether this observation was applicable to lambs exposed to a poor quality roughage like barley straw.
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Kyriazakis, I., J. D. Oldham, R. L. Coop y F. Jackson. "The effect of subclinical intestinal nematode infection on the diet seletion of growing sheep". British Journal of Nutrition 72, n.º 5 (noviembre de 1994): 665–77. http://dx.doi.org/10.1079/bjn19940070.
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To test the hypothesis that subclinical gastrointestinal parasitism, associated with an impairment in N digestion and metabolism and a reduction in the voluntary feed intake (VFI), could affect the diet selection of sheep given a choice between two feeds that differed in their crude protein (CP) content, twenty-four Texel ×Scottish Blackface ewe lambs growing from 28 to 48 kg live weight (LWT) were given a daily dose of 2500 larvae of the intestinal nematode Trichostrongylus colubriformis; twenty-four similar lambs were used as uninfected controls. Six infected and six control lambs were given a free choice between two pelleted feeds (10·4 MJ metabolizable energy/kg), wilh different CP contents (90 (L) and 214 (H) g CP/kg fresh feed respectively). In addition, eighteen parasitized and eighteen control sheep were given access ad lib. to either feed L, or feed H, or their mixture M (164 g CP/kg; twelve per feed), in order to quantify the effects of the feeds when offered alone, and to test for any interactions between feed CP content and parasitism on the performance of the lambs. Intestinal parasitism reduced significantly (P < 0·001) both the rates of LWT gain (by 30%) and VFI (by 10%). The adult and developing parasitic forms took 4 weeks to establish and develop to a significant adult worm population (as judged by the faecal egg counts and blood variables) and until then there was no effect of parasitism on the performance of the lambs. The diet selection of the lambs given a choice between two feeds was similar between the two groups in the first 4 weeks of the experiment, but differed significantly (P < 0·05) in the second part of the experiment (4th week to the end). Thus, while parasitized lambs had a reduced rate of feed intake, by changing their diet selection they achieved a daily rate of CP intake similar to the control ones. However, since the parasitized lambs had a reduced rate of LWT gain, they also consumed a higher total amount of CP to reach the same LWT. It is concluded that sheep infected daily with a small number of larvae of T. colubriformis and given a choice between two feeds that differ in their protein contents are able to modify their diet selection in order to meet the increased protein requirements resulting from such an infection.
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Hou, X. Z., D. H. Anderson, A. W. Illius, G. C. Emmans y J. D. Oldham. "Long-term patterns of food selection in sheep growing towards maturity". Proceedings of the British Society of Animal Production (1972) 1989 (marzo de 1989): 107. http://dx.doi.org/10.1017/s0308229600010989.
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Previous work at the Edinburgh School of Agriculture has suggested that sheep, like pigs, can select amongst foods which differ in protein:energy content according to their protein needs. The proportion of high protein feed which was selected by young sheep gradually diminished as the animals grew towards maturity over a period of measurement of 10 weeks (Cropper, 1988). The experiment reported here was designed to test this idea further by allowing sheep, initially differing in age and weight, to select between a high and low protein food (both available ad libitum) throughout their growth to a stable mature weight and body composition.Two pelletted feeds were formulated and prepared which differed in protein concentration but with similar calculated energy (metabolisable energy, ME) (Table 1) concentration and abundant in minerals and vitamins. Seven sheep (Suffolk x Greyface wethers) aged 3 months (n = 3), 18 months (n = 2), and 30 months (n = 2) at the start of the experiment were individually penned and given experience of each of the two feeds individually before having ad libitum access to both. Tap water was freely available from a bucket. Voluntary consumption of each feed was recorded daily by weighing and drying refusals. The sheep were weighed weekly and scanned using a Vetscan ultrasonic scanner to estimate fat and muscle depths at the 13th rib on days 126, 225, 336, 436 and 539.
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McDonald, CL, JB Rowe y SP Gittins. "Feeds and feeding methods for assembly of sheep before export". Australian Journal of Experimental Agriculture 34, n.º 5 (1994): 589. http://dx.doi.org/10.1071/ea9940589.
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Sheep are assembled in Australian feedlots before export and given time to adapt to the pelleted diet they will receive on board ship. In Western Australia, lupins are normally included in the diet at levels up to 30% as a source of digestible energy which is low in starch. It is also common to feed hay during assembly. We examine the use of pellets based on barley and containing either lupins or virginiamycin to overcome problems of acidosis, and the importance of hay during assembly. There were 9 dietary treatments each with 3 pens of 30 sheep. The study was conducted over 8 days simulating assembly feedlot conditions. Measurements were made of numbers of sheep visiting troughs (paint-marking technique) and accumulation of lactic acid in the rumen. 'Barley' pellets were formulated with 33% barley, 18% oats, 47% hay/straw and 2% minerals and vitamins. Replacing about half of the barley with lupins resulted in more sheep paint-marked on days 3-6 (P<0.05) and higher levels of feed intake on days 4-8 (P<0.001) than feeding pellets without lupins. The inclusion of lupins was also associated with a less pronounced drop in feed intake on day 4 than measured in sheep fed barley pellets alone. Adding virginiamycin at 40 g/t to the basal barley-based pellet also significantly increased the numbers of sheep paintmarked. Virginiamycin appeared to have a similar effect to the inclusion of lupins in terms of reducing the number of sheep which were not paint-marked. Sprinkling a small quantity of lucerne chaff onto the pellets had no effect on feeding behaviour. The use of hay in racks resulted in fewer sheep (3 v. 12%, P<0.05) not eating during the first 3 days but there was no significant effect thereafter. We concluded that the inclusion of either lupins or virginiamycin is effective in improving the adaptation to cereal-based pellets in export feedlots. The use of hay either in racks or sprinkled over the pellets appears to be of limited value.
Tesis sobre el tema "Sheep – Feeds"
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Hosking, Brenton John. "Evaluation of nutrient intake and digestion in grazing sheep receiving supplements : thesis submitted for the degree of Doctor of Philosophy". Title page, summary and contents only, 1987. http://web4.library.adelaide.edu.au/theses/09PH/09phh826.pdf.
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Includes bibliographical references (leaves 290-309) Investigates aspects of the intake and utilization of barley grain and grain legume supplements by sheep fed low quality pasture hay and when grazing mature summer pastures.
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Nolte, Joubert van Eeden. "An evaluation of degradable protein and nonprotein nitrogen on intake and digestion by Dohne merino sheep fed wheat straw". Thesis, Stellenbosch : Stellenbosch University, 2000. http://hdl.handle.net/10019.1/51597.
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Thesis (MSc)--Stellenbosch University, 2000.ENGLISH ABSTRACT: South Africa, like many other developing countries throughout the world, has a rapidly growing human population, resulting in a consequent increased demand for food. Ironically, this increased food supply has to be produced on a smaller area of available agricultural land, which means that agricultural production processes have to become more efficient. Furthermore, the majority of the people in these countries are unschooled and poverty is a common phenomenon. Therefore, animal scientists are faced with the challenge and the responsibility to provide affordable, high quality food to these people. One way of reaching this objective is to improve the utilisation of low-quality, high roughage feedstuffs like crop residues and dry natural grass pastures. In the winter rainfall area of South Africa alone, about 460 000 ha of wheat straw are annually available. The ruminant animal has the ability to utilise the relatively unavailable energy (cellulose, hemi-cellulose and pectin) in the fibre component of these low-quality forages. Unfortunately, various factors, of which a N deficiency is the pre-dominant one, limit the utilisation of these feedstuffs. If the ability of the ruminant to utilise low-quality, fibrous energy sources is improved, these abundantly available and relatively inexpensive crop residues and natural pastures can be converted into high quality protein food for human consumption. Therefore, in order to rectify the N deficiency caused by these low-quality forages, the supplemental N requirement to optimise the fermentation and digestive processes of the ruminant animal has to be determined. The first study was conducted to determine the supplemental rumen degradable protein (RDP) requirement, to maximise the digestible organic matter intake (DOMI) of Dohne Merino sheep fed wheat straw. Keeping the high cost of natural protein supplementation in mind, the purpose of the second study was to determine the amount of true protein that can be replaced by nonprotein nitrogen (NPN) in RDP supplements fed to Dohne Merino sheep consuming wheat straw. In both trials animals had ad libitum access to low-quality wheat straw (3.2% CP; 74.2% NDF) and water. In the first trial, RDP (calsium caseinate: 90% CP; 100% rumen degradable) was intraruminally administered at 07hOOand 19hOO,at the following levels: 0, 40,80, 120 and 160 gld. Intake, fermentation and digestion were monitored to determine the RDP requirement to maximise DOM!. Digestible organic matter (OM) intake displayed a quadratic increase with elevated amounts of RDP (P < .01), and was maximised at an estimated 3.15 g RDPlkg BW·75 or 11.6% of DOM. Forage OM intake tended to increase quadratically (P = .15) with higher RDP levels. Microbial nitrogen (MN) flow to the duodenum and microbial efficiency increased quadratically (P ~ .04) and fluid dilution rate tended to increase in a quadratic manner (P = .15) with increased RDP supplementation levels. Rumina! ammonia nitrogen (NH3-N) and total volatile fatty acid (VFA) concentrations increased linearly (P ~ .07), while rumen pH exhibited a variable response to increased RDP levels (cubic; P = .08). Increasing RDP supplementation to Dohne Merino wethers consuming wheat straw, generally enhanced forage utilisation and DOM!. In the second trial, urea replaced different levels of casein N on an isonitrogenous basis, ranging from 0 - 100%. Since true protein is much more expensive than urea, the purpose of this study was to determine the maximum natural protein level that can be replaced by urea in RDP supplements, without adversely affecting intake and/or fermentation and digestive processes. The control treatment provided all of the RDP in the form of calcium caseinate (90% CP; 100% rumen degradable). The percentages of supplemental RDP from urea in the other treatments were 25, 50, 75 and 100%. The 100% urea treatment was balanced with maize starch to contain 40% CP and all other treatments received the same amount (150 gld) of starch. Intake of forage OM showed a weak decreasing trend (linear; P = .16) with increasing urea levels. Ruminal digestibilities of OM and NDF were not affected (P ;;::.:18) by urea level. Increasing urea levels resulted in linearly reduced total tract OM and NDF digestibilities (P ~ .10). As a result, DOMI declined (linear; P < .01) with increasing proportions of urea. Effects of increasing urea proportions on duodenal N flow, microbial efficiency and fluid dilution rate were minimal. Ruminal NH3-N tended to increase quadratically with increasing urea levels (P = .l4). Total VFA concentration decreased linearly (P = .03), while rumen pH increased in a linear manner (P = .08) with increasing urea proportions. Branched-chain volatile fatty acids (BCVFA's) and valerate decreased linearly (P ~ .05) with increasing urea levels, while other VFA's and the acetate:propionate ratio were generally not affected by treatment (P ;;:::.16). It appears as though ruminal and total tract OM and NDF digestibility criteria, as well as DOMI reached maximum values at substituting 25% of casein for urea. It is therefore concluded that replacing 25% of casein with urea in RDP supplements, will maintain effective utilisation of low-quality forages by sheep.
AFRIKAANSE OPSOMMING: Ontwikkelende lande, insluitend Suid-Afrika, word gekenmerk deur 'n vmmge bevolkingsaanwas. Dit lei tot 'n verhoogde vraag na voedsel, wat op 'n gevolglik kleinerwordende beskikbare kommersiële lanbbou-area geproduseer moet word. Die doeltreffendheid van produksieprosesse in die landbousektor moet dus noodgedwonge verbeter word. Die oorgrootte meerderheid van die bevolkings in ontwikkelende lande is ongeletterd en armoede en hongersnood is soms 'n algemene verskynsel. Veekundiges word dus gekonfronteer met die uitdaging en verantwoordelikheid om bekostigbare, hoë kwaliteit voedsel aan hierdie mense te voorsien. Een van die mees doeltreffende metodes om hierdie probleem aan te spreek, is om die benutting van lae kwaliteit, hoë-vesel voerbronne, bv. oesreste en droë grasweidings te verhoog. In die winterreënstreek van Suid-Afrika alleen, is 460 000 ha koringstrooi jaarliks beskikbaar. Herkouers beskik oor die besondere vermoë om die relatief onbeskikbare energie (sellulose, hemi-sellulose en pektien) in die veselkomponent van hierdie lae kwaliteit voere te benut. Verskeie faktore, waarvan 'n N-tekort die mees prominente is, beperk egter die benutting van hierdie voerbronne. Die uitdaging is dus om die herkouer se vermoë om hierdie voere te benut, te optimaliseer. Sodoende word 'n geredelik beskikbare, onderbenutte en relatief goedkoop voerbron omgeskakel in hoë kwaliteit proteïen vir menslike gebruik. Die N-aanvullingsbehoefte om die fermentasie- en verteringsprosesse van die herkouerdier te optimaliseer moet dus bepaal word, sodat die N-tekort in herkouers, wat soortgelyke weidings benut, reggestel kan word. Gevolglik was die doel met die eerste proef om die behoefte aan rumen degradeerbare proteïen-(RDP)-aanvulling, vir die maksimum inname van verteerbare organiese materiaal (VOM) van Dohne Merino skape wat koringstrooi ontvang, te bepaal. Weens die hoë koste van natuurlike proteïenaanvulling, was die doel met die tweede proef om die hoeveelheid ware proteïen in RDP-aanvullings, vir Dohne Merino skape wat koringstrooi ontvang, wat met nie-proteïen stikstof (NPN) vervang kan word, te bepaal. In beide eksperimente het die diere ad libitum toegang tot koringstrooi (3.2% RP; 74.2% NBV) en water gehad. In die eerste proefis RDP (kalsiumkaseïnaat; 90% RP; 100% rumen degradeerbaar) teen 07hOOen 19hOOintraruminaal toegedien, teen die volgende peile: 0, 40, 80, 120 en 160 gld. Inname, fermentasie en vertering is gemonitor om die RDP behoefte vir die maksimum inname van VOM te bepaal. Verteerbare OM-inname het 'n stygende kwadratiese tendens (P < .01) getoon met verhoogde RDP-peile en het 'n maksimum bereik by 'n aanvullingspeil van 3.15 g RDPlkg metaboliese liggaamsmassa (LM·75 ) of 11.6% van VOM. Organiese materiaalinname vanaf koringstrooi het geneig om kwadraties toe te neem (P = .15) met verhoogde RDP-peile. Mikrobiese stikstof-(MN)-vloei na die duodenum en mikrobiese effektiwiteit het kwadraties toegeneem (P :::;.;04) en vloeistof deurvloeitempo het 'n neiging vir 'n kwadratiese toename (P = .15) met verhoogde RDPpeile getoon. Rumen-ammoniakstikstof (NH3-N) en vlugtige vetsuur-(VVS)-konsentrasies het lineêr toegeneem (P :::;.;07), terwyl rumen pH 'n wisselende reaksie (kubies; P = .08) met stygende RDP-peile getoon het. Verteerbare OM-inname en benutting van koringstrooi is verbeter deur stygende peile van RDP aanvulling by Dohne Merino hamels. In die tweede proef is kaseïen op 'n iso-stikstof basis met verskillende ureumpeile, vanaf o - 100%, vervang. Omdat ureum baie goedkoper is as natuurlike proteïen, was die doel van die tweede proef om die hoeveelheid natuurlike proteïen in RDP-aanvullings te bepaal wat met ureum vervang kan word, sonder om inname, fermentasie en vertering te benadeel. Die kontrolebehandeling het 100% van die RDP in die vorm van kalsiumkaseïnaat (90% RP; 100% rumen degradeerbaar) voorsien, terwyl ureum in die ander behandelings onderskeidelik 25, 50, 75 en 100% van die kaseïen-N vervang het. Die 100% ureumbehandeling is met mieliestysel tot 40% RP gebalanseer en dieselfde hoeveelheid stysel (150 gld) is by al die ander behandelings ingesluit, om moontlike effekte van stysel op rumenfermentasie te elimineer. Organiese materiaalinname vanafkoringstrooi het 'n swak dalende tendens getoon met stygende ureum insluitingsvlakke (lineêr; P = .16). Rumenverteerbaarheid van OM en neutraal bestande vesel (NBV) is nie deur die ureumpeil beïnvloed nie (P ;;:: .18). Toenemende ureumpeile het gelei tot 'n lineêre afname in totale kanaal OM en NBVverteerbaarheid (P ~ .10). Gevolglik het VOM inname lineêr afgeneem (P < .01) met stygende ureum insluitingspeile. Die effek van behandeling op duodenale N-vloei, mikrobiese effektiwiteit en vloeistof deurvloeitempo was minimaal. Rumenammoniakstikstof-( NH3-N)-konsentrasie het 'n stygende kwadratiese tendens getoon (P = .14) met toenemende ureum peile. Totale vlugtige vetsuur-(VVS)-konsentrasies het lineêr gedaal (P = .03), terwyl rumen pH lineêr toegeneem het (P = .08) met stygende ureum insluitingsvlakke. Vertakte ketting VVS' e en valeriaansuurkonsentrasies het lineêr gedaal (P ~ .05) met stygende ureumpeile, terwyl die ander VVS' e en die asynsuur:propioonsuurverhouding oor die algemeen nie deur behandeling beïnvloed N; nie (P ;;:: .16). Dit blyk asof VOM inname, sowel as rumen- en totale kanaal verteerbaarheidsmaatstawwe, by 25% vervanging van kaseïen-N met ureum-N 'n maksimum bereik het. Die gevolgtrekking is gemaak dat die doeltreffende benutting van lae kwaliteit ruvoere deur skape, gehandhaaf sal word deur 25% van die ware proteïen in RDP-aanvullings met ureum te vervang.
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Long, Amanda Marie. "Impacts of Flax on Female and Male Reproductive Traits When Supplemented Prior to Breeding in Sheep". Thesis, North Dakota State University, 2018. https://hdl.handle.net/10365/29877.
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Two experiments determined the effects of flaxseed supplementation on reproductive parameters in sheep. In experiment one, 240 multiparous Rambouillet ewes were assigned to one of two treatments: basal ration alone or basal ration with a Flaxlic® Sheep Tub offered over 35 days. Serum was collected weekly for progesterone (P4). Flaxseed supplementation did not improve progesterone concentration or reproductive parameters (P ≥ 0.26). In experiment two, 120 Rambouillet ram lambs were assigned to one of two treatments: basal ration alone or basal ration with a Flaxlic® Sheep Tub offered over 112 days. Scrotal circumference measurements, serum for testosterone, and semen were collected on day 84 and 112. Day effects were found for select semen measurements, testosterone, weight, and scrotal circumference (P ≤ 0.05). There was no effect of treatment on testosterone concentration (P = 0.99) or any semen quality characteristics (P ≥ 0.33). Overall, tub supplementation did not alter reproductive ability.
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Mey, Mahamat. "WEIGHT CHANGE, INTAKE AND DIGESTION OF ALFALFA HAY AND WHEAT STRAW BY KARAKUL, RAMBOUILLET AND ST. CROIX". Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/275269.
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Mavimbela, David Thele. "The nutritional value of broiler litter as a feed source for sheep during periods of feed shortage". Thesis, Pretoria : [s.n.], 1999. http://upetd.up.ac.za/thesis/available/etd-12152006-153846.
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Zhang, Runhou 1963. "Manipulating fatty acids in sheep milk". Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=102236.
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Four studies were conducted to investigate some factors affecting milk fatty acid composition of dairy ewes. The first study was performed to determine the influence of freezing temperatures and storage time on ovine milk composition and cheese making. The other three experiments were conducted to examine the effects of dietary added fats with different profiles of fatty acids from canola, sunflower and flaxseeds on animal performance, nutrient utilization, milk yield and cheese making. The main emphasis was on fatty acid composition, particularly CLA and Omega-3 fatty acids, in milk and cheese. Results showed that: (1) feeding up to 8% of canola, sunflower and flaxseed had no adverse effects on dry matter intake and total tract digestibilities of dry matter, neutral detergent fiber, acid detergent fiber and crude protein, while the digestibilities of fatty acids and gross energy were increased with oilseed supplementation; (2) feeding flaxseed to lactating ewes up to 260g/ewe/d increased milk yield by up to 8.4%, and fat content by up to 14.3% without adversely affecting other milk components or cheese yield and composition; (3) Oilseed supplementation increased milk concentrations of long-chain and unsaturated fatty acids in the expenses of short-chain, medium-chain and saturated fatty acids. The concentrations of CLA and Omega-3 fatty acids were also increased by oilseed supplementation; (4) the manipulated fatty acids profiles can be reflected in cheese; (5) good quality cheese can be produced from ovine milk frozen at -15°C and -25°C for up to 6 months without influencing cheese content of fat and protein and fatty acid composition.In conclusion, ovine milk with nutritionally healthy characteristics can be produced by feeding ewes diets with oilseeds, and freezing storage of milk for up to 6 months at -15°C or -25°C does not significantly affects milk composition including fatty acid composition. The characteristics of milk can be reflected in cheese.
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Baah, John. "Effect of particle size distribution in the reticulo-rumen, omasum and abomasum of sheep on voluntary intake and digestibility of forages". Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/28887.
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This study was designed to provide information on some of the factors affecting voluntary consumption and digestibility of forages by sheep. A wet sieving procedure was used to determine particle size distribution in the reticulo-rumen, omasum and abomasum of sheep fed 100 % prebloom alfalfa or 100 % second-cut Altai wild ryegrass hays or mixtures of these with tall wheatgrass or Altai wild ryegrass straws. The study also compared second-cut Altai wild ryegrass and prebloom alfalfa as components in an all forage diet for sheep. Each diet was fed ad libitum to eight Romanov x Western whiteface wether lambs weighing 22 to 25 kg during the intake and digestibility trials. For the determination of particle size distribution, the animals were slaughtered at 12, 24, 36, and 48 hours after feed removal and the contents of the reticulo-rumen, omasum and abomasum sampled.
Five different methods of describing digesta particle size distribution were compared as to their ability to predict voluntary intake and digestibility of the forages by sheep.
The best method for expressing particle size distribution in the reticulo-rumen in terms of ability to predict dry matter digestibility (DMD) was the proportion of soluble dry matter in total dry matter (PSDM). A significant (P< 0.05) correlation (r = 0.84) between PSDM and dry matter digestibility, 12 hours after feed removal was obtained. PSDM in omasal digesta 24 hours after feed removal was also highly correlated with DMD and energy digestibility (r = 0.97, 0.91, respectively). Very high correlations were obtained between PSDM in abomasal digesta 24 hours after feed removal and digestibility of cellulose, NDF and ADF (r = 0.99, 0.97 and 0.97 respectively). The proportion of particles less than 1mm to the total particles (PIP) in the reticulo-rumen gave the most
consistent correlations with intake of dry matter and energy.
Voluntary intake of dry matter by the animals on the alfalfa-based diets were significantly
higher (P< 0.05) than those on the second-cut Altai wild ryegrass-based diets. However, the apparent digestibility coefficients of the proximate fractions in the Altai wild ryegrass diets were significantly higher (P< 0.05) than those of diets containing alfalfa.
Daily intake of digestible energy by animals on 100 % alfalfa was not significantly different from that of animals on 100 % second-cut Altai wild ryegrass. The difference between their respective combinations with tall wheatgrass and Altai wild ryegrass straws were also not significant.
It was concluded that PIP and PSDM are indeces based on biologically significant fractions and may therefore have greater relevance than purely mathematical or statistical
descriptions of particle size distribution in digesta. In this regard, the relationship between PSDM and digestibility and, PIP and intake are consistent with published theory and can be used in mathematical models to examine control processes in feed intake, rate of passage and digestion. The study also indicated that second-cut Altai wild ryegrass harvested at the prebloom stage can be used as a substitute for alfalfa in an all-forage diet for winter feeding of sheep.Land and Food Systems, Faculty of
Graduate
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Aucamp, Barend Bernadus. "Byvoeding van skape op aangeplante weiding in 'n mediterreense klimaat". Thesis, Port Elizabeth Technikon, 2001. http://hdl.handle.net/10948/44.
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Tydens embrio ontwikkeling groei weefsel deur selvermeedering, maar soos wat soogdiere volwassendheid nader vind groei net plaas deur sel vergroting. Volwassenheid word beskou as wanneer spiergroei ‘n maksimum bereik. Groei sluit die neerlegging van vet in, maar spiermassa is van primêre belang. Die groeikurwe (Fig 1) waarin massatoename teenoor ouderdom vergelyk word, volg ‘n sigmoidale kurwe (Owens et al, 1993). Onder ideale toestande is die groeitempo van lammers relatief konstant van kort na geboorte totdat die helfte van volwassemassa bereik word, waarna dit geleidelik afneem tot volwassenheid (Black, 1983). Die afname in groeitempo begin gewoonlik met die bereiking van puberteit (Owens et al, 1993).
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Wegeler, Claudia. "Transport von HCO₃⁻ am isolierten Psalterepithel des Schafes : Charakterisierung und Einfluss der Fütterung". Berlin mbv, 2007. http://d-nb.info/988716968/04.
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Zugl.: Berlin, Freie Univ., Diss., 2007"The aim of this work was to characterize the HCO₃⁻ Transport of the omasum and to look for possible alterations after the change from hay to concentrate feeding."
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Ilse, Breanne Rose. "Effects of Linseed Meal on Growth and Reproductive Performance in Ruminants". Thesis, North Dakota State University, 2011. https://hdl.handle.net/10365/28744.
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Linseed meal (LSM) was fed to ovariectomized ewes exposed to estradiol 17-? (E2)
implants over time, and LSM was supplemented to beef cows during late gestation and
early lactation to evaluate the estrogenic potential of the phytoestrogen secoisolariciresinol
diglycoside (SDG) found in LSM. Forty-eight ovariectomized ewes were fed a diet
containing 12.5% LSM for 0, 1, 7, or 14 d and implanted with estradiol-17? (E2) for 0, 6,
or 24 h before tissue collection. Uterine cellular proliferation, vascularity, and the
expression of the angiogenic factors and their receptors were recorded. There was an
interaction of LSM and E2 on uterine mass (P = 0.05). At 24 h of E2 exposure,
proliferation was reduced (P < 0.001) when ewes were fed for 14 d compared to being fed
0 or 1 days. There was a LSM x E2 interaction (P ? 0.03) on VEGF receptor-2 (KDR) and
hasicfihrohlast growth factor receptor (FGFR2) decreasing by 24 h E2 exposure.
Exposure of LSM and E2 may impact the estrogenic response of sensitive tissue.
Two studies were conducted to examine the effects of supplementing beef cows
with LSM during late gestation or early lactation on calf growth and development. In
Experiment 1, multiparous cows received either LSM or a control (CON) supplement
(approximately 10% diet dry matter) for the last 60 d of gestation. Offspring weights,
ADG, heifer age at puberty, conception percentage and steer carcass characteristics were
recorded. In Experiment 2, multiparous cows received LSM or CON supplements
(approximately 10% diet dry matter) during the first 60 d of lactation, and only heifer calf
development performance was observed and recorded. Heifer calf weight, average daily
gain, and attainment of puberty were assessed. For both experiments, birth weight, weaning
weight and ADG were not affected (P > 0.31) by LSM supplementation. While final body
weights were heavier (P = 0.04) for steer calves in Experiment 1, there was no effect (P =
0.09) of supplementation on carcass characteristics. In Experiment 1 and 2, attainment of
puberty in heifer calves was not influenced (P > 0.58) by supplement type. Linseed meal
supplementation during late gestation or early lactation does not appear to have a negative
impact on calf growth, onset of puberty in heifer calves, or steer carcass quality,
implicating that it may make a good supplement choice in cattle.
Libros sobre el tema "Sheep – Feeds"
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Mason, B. D. Nutrition guide for B.C. sheep producers. [Victoria, B.C.?]: Province of British Columbia, Ministry of Agriculture and Food, 1985.
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Pedersen, E. J. Nørgaard. Sammenligning af fordøjelig energi bestemt ved kalorimetri og beregnet ud fra den kemiske sammensætning af det fordøjelige organiske stof =: A comparison of digestible energy measured by calorimetry and calculated from the chemical composition of the digestible organic matter. Lyngby: Statens planteavlsudvalg og statens husdyrbrugsudvalg, 1989.
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Richard, D. Essais d'alimentation de moutons au Niger. Paris: Institut d'élevage et de médecine vétérinaire des pays tropicaux, 1985.
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Thomson, E. F. Feeding systems and sheep husbandry in the barley belt of Syria. Aleppo, Syria: International Center for Agricultural Research in the Dry Areas, 1987.
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O'Mara, Frank. A net energy system for cattle and sheep. Dublin: University College Dublin. Department of Animal Science and Production, 1996.
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Tyler, Roger. Feeding sugar beet pulp. Alnwick: Ministry of Agriculture, Fisheries and Food, 1988.
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Hinton, David G. Supplementary feeding of sheep and beef cattle. 2a ed. Collingwood, VIC: Landlinks, 2007.
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Byrne, William. An evaluation of nutritional strategies and sire breed for mid-season lamb production. Dublin: University College Dublin, 1999.
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Solomon, Ayele. Evaluation of selected multipurpose trees as feed supplements in tef (Eragrostis tef) straw based feeding of Menz sheep. Berlin: Köster, 2001.
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Madero, Francisco Javier Alonso. La oveja Manchega. Cuenca: Excma. Diputación Provincial de Cuenca, 1992.
Buscar texto completoCapítulos de libros sobre el tema "Sheep – Feeds"
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Jones, B., N. J. Leighton y H. Fletcher. "Programmable Sheet Feed System For A Computer Controlled Press". En Proceedings of the Twenty-Seventh International Matador Conference, 121–28. London: Macmillan Education UK, 1988. http://dx.doi.org/10.1007/978-1-349-09912-2_19.
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Verkerk, Dorothy Hoogland. "Feed My Sheep: Pastoral Imagery and the Bishops’ Calling in Early Ireland". En Medieval Church Studies, 157–79. Turnhout: Brepols Publishers, 2014. http://dx.doi.org/10.1484/m.mcs-eb.1.102231.
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Domingue, B. M. Francoise, D. W. Dellow, P. R. Wilson, G. F. Wilson y T. N. Barry. "Voluntary Feed Intake and Digestion in Farmed Red Deer Stags: A Comparison with Goats and Sheep". En The Biology of Deer, 459. New York, NY: Springer New York, 1992. http://dx.doi.org/10.1007/978-1-4612-2782-3_107.
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Kumar, Ajay, Parveen Kumar y Hari Singh. "Influence of Wall Angle, Feed Rate, and Sheet Thickness on Forming Force in SPIF". En Advances in Materials and Mechanical Engineering, 329–38. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-16-0673-1_26.
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Benoit, Marc y Gabriel Laignel. "Optimisation of Breeding Systems and Land Use to Maximise Feed Self-Sufficiency and Economic Outcomes in Organic Sheep-for-Meat Production". En Organic Farming, Prototype for Sustainable Agricultures, 181–200. Dordrecht: Springer Netherlands, 2014. http://dx.doi.org/10.1007/978-94-007-7927-3_10.
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Medjekal, Samir y Mouloud Ghadbane. "Sheep Digestive Physiology and Constituents of Feeds". En Sheep Farming - An Approach to Feed, Growth and Health. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.92054.
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Sheep have a gastrointestinal tract similar to that of other ruminants. Their stomach is made up of four digestive organs: the rumen, the reticulum, the omasum and the abomasum. The rumen plays a role in storing ingested foods, which are fermented by a complex anaerobic rumen microbiota population with different types of interactions, positive or negative, that can occur between their microbial populations. Sheep feeding is largely based on the use of natural or cultivated fodder, which is exploited in green by grazing during the growth period of the grass and in the form of fodder preserved during the winter period. Ruminant foods are essentially of plant origin, and their constituents belong to two types of structures: intracellular constituents and cell wall components. Cellular carbohydrates play a role of metabolites or energy reserves; soluble carbohydrates account for less than 10% dry matter (DM) of foods. The plant cell wall is multi-layered and consists of primary wall and secondary wall. Fundamentally, the walls are deposited at an early stage of growth. A central blade forms the common boundary layer between two adjacent cells and occupies the location of the cell plate. Most of the plant cell walls consist of polysaccharides (cellulose, hemicellulose and pectic substances) and lignin, these constituents being highly polymerized, as well as proteins and tannins.
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Fajt, Virginia R., Kenneth R. Brown y David G. Pugh. "Commonly used drugs and veterinary feed directive in sheep, goats, and cervids". En Sheep, Goat, and Cervid Medicine, 517–38. Elsevier, 2021. http://dx.doi.org/10.1016/b978-0-323-62463-3.00030-x.
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Barker, Graeme. "Approaches to the Origins of Agriculture". En The Agricultural Revolution in Prehistory. Oxford University Press, 2006. http://dx.doi.org/10.1093/oso/9780199281091.003.0006.
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Humans have occupied our planet for several million years, but for almost all of that period they have lived as foragers, by various combinations of gathering, collecting, scavenging, fishing, and hunting. The first clear evidence for activities that can be recognized as farming is commonly identified by scholars as at about 12,000 years ago, at about the same time as global temperatures began to rise at the end of the Pleistocene (the ‘Ice Ages’) and the transition to the modern climatic era, the Holocene. Subsequently, a variety of agricultural systems based on cultivated plants and, in many areas, domesticated animals, has replaced hunting and gathering in almost every corner of the globe. Today, a relatively restricted range of crops and livestock, first domesticated several thousand years ago in different parts of the world, feeds almost all of the world’s population. A dozen crops make up over 80 per cent of the world’s annual tonnage of all crops: banana, barley, maize, manioc, potato, rice, sorghum, soybean, sugar beet, sugar cane, sweet potato, and wheat (Diamond, 1997: 132). Only five large (that is, over 100 pounds) domestic animals are globally important: cow, sheep, goat, pig, and horse. The development of agriculture brought profound changes in the relationship between people and the natural world. Archaeologists have usually theorized that, with the invention of farming, people were able to settle down and increase the amount and reliability of their food supply, thus allowing the same land to support more people than by hunting and gathering, allowing our species tomultiply throughout the world. The ability to produce food and other products from domesticated plants and animals surplus to immediate subsistence requirements also opened up new pathways to economic and social complexity: farming could mean new resources for barter, payment of tax or tribute, for sale in a market; it could mean food for non-food producers such as specialist craft-workers, priests, warriors, lords, and kings. Thus farming was the precondition for the development of the first great urban civilizations in Egypt, Mesopotamia, the Indus valley, China, the Americas, and Africa, and has been for all later states up to the present day.
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Thomson, E. F., P. S. Cocks y F. Bahhady. "Improving feed resources: a key step towards expanding ruminant production in semiarid north Africa and west Asia". En New Techniques in Sheep Production, 197–203. Elsevier, 1987. http://dx.doi.org/10.1016/b978-0-408-10134-9.50027-3.
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Oraon, Manish, Manish Kumar Roy y Vinay Sharma. "Investigating the Effect of Process Parameters in Incremental Sheet Forming Process". En Advances in Civil and Industrial Engineering, 24–36. IGI Global, 2021. http://dx.doi.org/10.4018/978-1-7998-7206-1.ch003.
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Incremental sheet forming (ISF) is an emerging technique of sheet metal working that comes into the picture in the last two decades. The ISF involved the forming of shapes without using the dedicated dies. ISF is suitable for customized products, rapid prototyping, and low batch production. The study aims to investigate the effect of process parameters on the surface roughness. The experiments are conducted on aluminum AA3003-O grade with six parameters, and the trials are performed according to the design of experiment (DOE). The atomic force microscopy (AFM) technique is used for measuring the surface roughness. Analysis of variance (ANOVA) is used for analyzing the effect of process parameters in ISF. The result shows that the step-down size, feed rate of the tool, and wall angle are significant process parameter and their contributions for ISF are 85.86%, 1.12%, and 12.29%, respectively.
Actas de conferencias sobre el tema "Sheep – Feeds"
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Tonobey, H. Al y H. M. El Shaer. "Utilization of agricultural residues as animal feeds for fattening sheep in Saudi Arabia". En The Sustainable World. Southampton, UK: WIT Press, 2010. http://dx.doi.org/10.2495/sw100381.
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Junqueira, Flavio P., Vincent Leroy, Marco Serafini y Adam Silberstein. "Shepherding social feed generation with Sheep". En the Fifth Workshop. New York, New York, USA: ACM Press, 2012. http://dx.doi.org/10.1145/2181176.2181183.
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Mwita, W. M. y E. T. Akinlabi. "Numerical Investigation on Strain Properties of Ti6Al4V Alloy Processed by Constrained Bending and Straightening Severe Plastic Deformation". En ASME 2019 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/imece2019-11163.
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Abstract This paper presents a numerical investigation on strain properties of Ti6Al4V alloy processed by constrained bending and straightening (CBS) severe plastic deformation (SPD) technique. CBS is a new SPD method that has been proposed to enhance continuous processing of metal sheets and improve magnitude and homogeneity of induced properties such as strain. The model considers a rectangular sheet of Ti6Al4V alloy processed with CBS at 2, 4 passes denoted as N2, N4 each combined with 10, 5, 3 mm feed length denoted as F10, F5, F3 respectively. ABAQUS Standard FEA Software was used to simulate and investigate the magnitude and homogeneity of equivalent plastic (EP) strain induced in material. Results show that for all feeds, magnitude values of EP strain at N4 passes were higher than those at N2 passes. The magnitude of EP strain increased with the number of passes. Values of both magnitude and homogeneity of EP strain were highest at F3 feed followed by those at F5 and F10 feeds respectively. The study has promised that CBS is the potential process for continuous production of metal sheets with improved EP strain magnitude and homogeneity.
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Sregar, Hairani y Etti Sartina Siregar. "Socio-economic empowerment of thick-tailed-sheep livestock 'through feed variation technology (feed fermentation)". En 2nd International Conference on Social and Political Development (ICOSOP 2017). Paris, France: Atlantis Press, 2018. http://dx.doi.org/10.2991/icosop-17.2018.82.
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Begembekov, K. N., A. A. Torekhanov, K. Z. Amanbaev, E. S. Akhanov y E. B. Ospanov. "ECONOMIC EFFICIENCY OF BREEDING OF AKTOHAYSKY SHEEP IN SCAN FODDING CONDITIONS OF DESERT ZONES OF CENTRAL KAZAKHSTAN". En STATE AND DEVELOPMENT PROSPECTS OF AGRIBUSINESS Volume 2. DSTU-Print, 2020. http://dx.doi.org/10.23947/interagro.2020.2.516-520.
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The article presents the results of a study on the cost-effectiveness of breeding of Kazakh fat tail sheep, Edilbaev and Aktogay semi-coarse sheep in harsh climatic conditions, poor feed conditions with year-round grazing in the desert zone of Central Kazakhstan. It has been established that in this zone, the most profitable, both from the point of view of obtaining the highest, higher quality products, and economic efficiency, is the breeding of Aktogai populations of semi-coarse fat tail sheep.
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Yoshida, Kazushi. "Theoretical Study on Features of an Overlap-Type and a Pressing-Type Sheet Separation Mechanisms". En ASME-JSME 2018 Joint International Conference on Information Storage and Processing Systems and Micromechatronics for Information and Precision Equipment. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/isps-mipe2018-8541.
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We examined the behaviors of the paper sheet in an overlap-type sheet separation mechanism and a pressing-type sheet separation mechanism. First, we introduced the models that can calculate the resistance force and feed force acting on the paper sheets in both sheet separation mechanisms. And, based on the calculation results of the resistance force and friction force between the paper sheets, we studied the behavior of the paper sheet in each separation mechanism. As a result, we found that an overlap-type sheet separation mechanism is superior to the pressing-type sheet separation mechanism but it is easily influenced by the feeding force caused by pick-up rollers, and also a pressing-type sheet separation mechanism has robustness for a thickness of paper sheet and for a feeding force caused by pick-up rollers.
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Ndukaife, Kennethrex O. y George Agbai Nnanna. "Characterization of Fouled Flat Sheet Membranes by Infrared Thermography". En ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-36761.
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An Infrared thermography (IRT) technique for characterization of fouling on membrane surface has been developed. The emitted spectral power from the fouled membrane is a function of emissivity and surface morphology. In this work, a FLIR A320 IR camera was used to measure surface temperature and emissivity. The surface temperature and the corresponding emissivity value of various areas on the fouled membrane surface is measured by the infrared camera and recorded alongside its thermogram. Different fouling experiments were performed using different concentrations of aluminum oxide nanoparticle mixed with deionized water as feed solution (333 ppm, 1833 ppm and 3333 ppm) so as to investigate the effect of feed concentration on the degree of fouling and thus its effect on the emissivity values measured on the membrane surfaces. Surface plots in 3D and Line plots are obtained for the measured emissivity values and thickness of the fouling deposit on the membrane surface respectively. The results indicate that the IRT technique is sensitive to changes that occur on the membrane surface due to deposition of contaminants on the membrane surface and that emissivity is a function of temperature, surface roughness and thickness of the specimen under investigation.
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ISMAILOV, Ismail Sagidovich, Nina Vladimirovna TREGUBOVA, Rashid Hasanbievich KOCHKAROV, Anna Victorovna MORGUNOVA y Natalija Alecseevna DRIZHD. "THE RELATIONSHEEP OF AMINO ACID METABOLISM WITH PRODUCTIVITY OF GROWING YOUNG SHEEP". En RURAL DEVELOPMENT. Aleksandras Stulginskis University, 2018. http://dx.doi.org/10.15544/rd.2017.125.
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A number of studies on digestion of the ruminants have shown the process of synthesis of all the essential amino acids in the rumen (Abu Fadel, 2004; Trukhachev, V., Zlidnev, N. 2008). However, according to some researches, microbial protein is deficient in methionine and lysine. This assumption also proves the need for further study of the influence of balanced amino acids to these diets on the growth, development and productive performance of the ruminants. Scientific approbation of the issues related to establishing the requirements of young sheep in lysine and methionine with cystine and development of recommendations for their proper balance in animal rations have been conducted along with a series of physiological, scientific and practical experiments. For this purpose, we used the following research methods: preparative, analytical, measuring and calculating. Zootechnical evaluation of young sheep’s diet with different levels of lysine and methionine with cysteine has been conducted, and influence of these components on growth, development, metabolism, the use of amino acids and wool productivity have been studied. The importance of studying the content of amino acids in plasma is evident because they are the indicators of protein metabolism in the animals’ organism and represent themselves the exchange fund when used in the biochemical transformations in the process of updating the protein of the body tissues and the synthesis of animal products. Increase in young sheep’s diet of lysine and methionine can improve their productivity, reduce the cost of feed energy and improve biochemical indexes of meat, taking into account the optimization of its amino acid composition. Efficiency increase of young sheep during the process of the individual development is linked to conditions of feeding and in particular the usefulness of a protein food, which is primarily determined by sufficient intake of essential amino acids - lysine and methionine with cystine. Thus, the inclusion in the diet of growing young sheep some amount of synthetic amino acids – 6–8 grams of lysine and 3–4 g of methionine per 1 fodder unit, enhances oxidation-reduction processes, increase productivity, i.e. wool yield and other indicators. The content of free amino acids in plasma directly depends on their availability in feed. The use of synthetic amino acids (lysine, methionine and cystine) contributed to the increase of their content in a free state in the blood serum, indicating their increased demand in sheep. With the use of different doses of synthetic amino acids (lysine, methionine, cystine) in the diets of young sheep it has been found that the organization of optimum conditions of feeding, care and management of sheep in winter season help to avoid abrupt changes in the structure of the skin, to ensure the normal development of the histological structure and morphogenetic processes.)
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Wang, Yongjun, Weichao Wu, Ying Huang, N. Venkata Reddy y Jian Cao. "Experimental and Numerical Analysis of Double Sided Incremental Forming". En ASME 2009 International Manufacturing Science and Engineering Conference. ASMEDC, 2009. http://dx.doi.org/10.1115/msec2009-84275.
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This paper presents a new rapid prototyping process of a thin sheet metal, Double Sided Incremental Forming of a cylindrical part without a die or a clamping device around the periphery of the sheet. The effects of process parameters on part shape, such as gap between two tool heads and feed rate, are examined experimentally with a special device mounted on a general lathe and numerically with a commercial finite element software package, Abaqus. Depending on the process parameter, a truncated cone shape part can be successfully fabricated with two tool heads pressing and moving along the radial direction of the sheet, which is held by lathe spindle at its center. A simple mathematic model to predict the cone angle is proposed and compared well with experimental data.
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Khalifa, Atia E., Dahiru U. Lawal y Mohamed A. Antar. "Performance of Air Gap Membrane Distillation Unit for Water Desalination". En ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-36031.
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Due to water scarcity in the Arabic gulf region, water desalination technologies are considered extremely important. The present work represents a fundamental study on the effect of basic operating and design variables on the flux of an air gap membrane distillation (AGMD) unit for water desalination. The flat sheet, channeled air gap membrane distillation module was designed and manufactured locally. The effect of feed flow rate, feed temperature, coolant water temperature, the air gap width, and the water salinity on the module flux are investigated. Analytical model for heat and mass transfer is used to predict the flux and the model results are compared to the experimental ones. Results showed that the technique has good potential to be used for water desalination. The permeate flux is increased by increasing feed flow rate, feed temperature, decreasing the air gap width, decreasing coolant temperature, and decreasing salinity of feed water. For a given feed flow rate, the width of the air gap and the feed water temperature are found to be the most effective parameters in increasing the distillate flux. Predicting the permeate flux with analytical models for heat and mass transfer showed good agreement with experimental results.
Informes sobre el tema "Sheep – Feeds"
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Matlack, Keith S., Howard Abramowitz, Isabelle S. Muller, Innocent Joseph y Ian L. Pegg. DFLAW Glass and Feed Qualifications to Support WTP Start-Up and Flow-Sheet Development (Final Report, Rev. 0). Office of Scientific and Technical Information (OSTI), noviembre de 2017. http://dx.doi.org/10.2172/1529091.
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