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Amino acid requirements of feedlot cattle according to the duodenal and whole empty body essential amino acid profileErasmus, Morné 12 1900 (has links)
Thesis (MScAgric)--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: The purpose of this study was to determine the essential amino acid requirements of
beef cattle under feedlot conditions through evaluation of the duodenal and whole empty
body essential amino acid compositions. To define the ideal protein required for growth,
the whole empty body essential amino acid compositions of 8 beef steers (Simmental
and Hereford crosses) was investigated. The amino acid composition of the components
(carcass, metabolic organs and residual fraction), was pooled relative to their respective
mass and protein contribution, resulting in the calculated whole empty body amino acid
composition: arginine 6.81; histidine 2.69; isoleucine 4.02; leucine 6.96; lysine 7.43;
methionine 2.01; phenylalanine 4.03; threonine 4.01; valine 5.30; tryptophan 0.82.
Variations in profiles were found between scientific reports, either indicating that ratios
change with growth and implants or possibly through genotype.
The present study's body amino acid ratios were used to estimate dietary amino acid
requirements through evaluation of the duodenal essential amino acid compositions from
three different maize based feedlot diets. Although there was a general increase in the
biological value of protein after rumen fermentation, the duodenal essential amino acids
in comparison with the whole empty body recorded deficient/unbalanced profiles of
essential amino acids for growth. The chemical scores suggested that the first-to-thirdlimiting
amino acids in the duodenal digesta of beef cattle, that received three different
commercially available feedlot diets, were: histidine, lysine, methionine/arginine (Diet 1),
histidine, arginine, lysine (Diet 2) and arginine, methionine, histidine (Diet 3). Thedisproportionate duodenal amino acid concentrations obtained from the three diets,
emphasise the necessity to enhance the intestinal delivery of amino acid profiles through
different undegradable protein sources, with the objective to maximise protein utilisation
and obtain the genetic potential for optimal growth in feedlot cattle.
When amino acid requirements and flows to the duodenum were simulated using the
Cornell Net Carbohydrate and Protein system (CNCPS), predictions indicated that lysine
amino acid flow was limiting the metabolizable allowable average daily gain in Diet 1 and
3. Predicted profiles indicated that the order of limitation was: lysine, arginine, histidine
(Diet 1), lysine, arginine, histidine, methionine (Diet 2) and lysine, arginine, histidine (Diet
3). The predicted profiles were in accordance with observed duodenal values, except for
methionine that was observed limiting in Diet 1 and 3; however, the sequence and extent
of limitation varied. Results indicate that prediction models have potential in predicting
requirements; however there are still limitations for use to accurately define
requirements for particular EAA's.
From the present study, it is clear that the protein accretion was constrained by quantity
and/or disproportionality of amino acids available for absorption. Further research should
therefore be directed towards obtaining a more desirable array of amino acids to the
lower digestive tract that is digestible, absorbable and an economically viable option for
the feedlot operator. / AFRIKAANSE OPSOMMING: Aminosuurbehoeftes van Voerkraalbeeste Volgens die
Duodenale en Totale Lee Liggaam Essensiele Aminosuur
Profiel: Die doel van hierdie studie was om die essensiele aminosuur vereistes van vleisbeeste
onder voerkraal toestande te bepaal deur die evaluering van die duodenale en totale lee
liggaam essensiele aminosuursamesteilings. Om die idea Ie proteiene wat vir groei
benodig word te definieer, is 'n ondersoek ingestel na die totale lee liggaam essensiele
aminosuursamesteilings van 8 vleisbees osse (Simmetailer en Hereford kruise). Die
aminosuursamesteiling van die komponente (karkas, metaboliese organe en residuele
fraksie), se massa en proteien bydrae is gebruik om die totale lee liggaam
aminosuursamestelling 5005 volg te bereken: arginien 6.81; histidien 2.69; isoleusien
4.02; leusien 6.96; lisien 7.43; metionien 2.01; fenielalanien 4.03; treonien 4.01; valien
5.3; triptofaan 0.82. Variasies in profiele tussen wetenskaplike verslae is gevind. Dit dui
daarop dat groei en inplantings of moontlik genotipe 'n invloed op profiele kan he.
Die huidige studie se liggaam aminosuurverhoudings is gebruik om die dieet
aminosuurbehoeftes te skat deur evaluering van die duodenale essensiele
aminosuursamesteilings van drie verskiilende mielie-gebaseerde voerkraal diete.
Alhoewel daar 'n algemene toe name in die biologiese waarde van die proteien na
rumen fermentasie was, het die duodenale essensiele aminosure in vergelyking met die
totale lee liggaam, ongebalanseerde profiele van essensiele aminosure vir groei getoon.
Die chemiese teilings toon aan dat die eerste-tot-derde-beperkende aminosure in die
duodenale inhoud van vleisbeeste wat drie verskillende kommersieel beskikbare
voerkraal diete ontvang het, soos volg is: histidien, lisien, metionieniarginien (Dieet 1), histidien, arginien, lisien (Dieet 2) en arginien, metionien, histidien (Dieet 3). Die
ongebalanseerde aminosuur konsentrasies wat in die duodenum van die drie dlete
verkry is, beklemtoon die noodsaaklikheid om die intestinale lewering van
aminosuurprofiele te verbeter deur verskillende nie-degradeerbare proteien bronne te
voer. Die doelwit moet wees om proteien verbruik te optimaliseer en daardeur die
genetiese potensiaal vir optimale groei in voerkraalbeeste te bereik.
Met die simulering van aminosuurbehoeftes en vloei na die duodenum van die drie
standaard voerkraal diete met behulp van die "Cornell Net Carbohydrate and Protein
System" (CNCPS), het voorspellings gewys dat lisien aminosuurvloei die
metaboliseerbare toelaatbare gemiddelde daaglikse toename in Dieet 1 en 3 beperk het.
Voorspelde profiele wys dat die volgorde van beperking soos volg sou wees: lisien,
arginien, histidien (Dieet 1), lisien, arginien, histidien, metionien (Dieet 2)' en lisien
arginien, histidien (Dieet 3). Die voorspelde profiele was in ooreenstemming met die
waargeneemde duodenale waardes, behalwe vir metionien wat beperkend was in Dieet
1 en 3; die volgorde en mate van beperking was egter verskillend. Resultate wys dat
voorspellingsmodelle die potensiaal het om behoeftes te voorspel. Vir die akkurate
definisie van behoeftes vir spesifieke essensiele aminosuure is daar egter nog
beperkinge.
Uit die huidige studie, is dit duidelik dat protetenneerleqqinq deur die hoeveelheid en/of
oneweredigheid van geabsorbeerde aminosure beperk is. Verdere navorsing moet dus
fokus op die verkryging van In meer geskikte profiel van aminosure wat verteerbaar,
opneembaar en 'n ekonomiese lewensvatbare opsie vir die voerkraalbestuurder is.
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RATE OF PASSAGE, RATE OF DIGESTION, AND RUMEN ENVIRONMENTAL CHANGES AS INFLUENCED BY ROUGHAGE SOURCE IN 65 AND 90% CONCENTRATE DIETS FOR STEERS.MOORE, JEANNETTE AILEEN. January 1987 (has links)
Diets were based on steam-flaked milo and contained chopped alfalfa hay in the control diet. At the 65% concentrate level, cottonseed hulls or chopped wheat straw replaced half the alfalfa hay. At the 90% concentrate level, roughage sources were chopped alfalfa hay, cottonseed hulls, or wheat straw. Six growing steers and three mature, rumen-cannulated steers per concentrate level were used in separate Latin square experiments. Total tract digestion coefficients, particulate passage rates, liquid turnover rates, and rumination time were measured in the intact steers. In situ digestion, rumen pH, and rumen dry matter distribution were evaluated in the cannulated steers. Competition between rates of passage and digestion were used to calculate apparent extent of ruminal digestion (AED). At the 65% concentrate level, total tract digestion coefficients for the wheat straw vs alfalfa hay diet were not different, apparently due to increased milo and alfalfa hay neutral detergent fiber (NDF) digestion in the wheat straw diet. Milo and alfalfa hay AED for NDF were higher (P<.10). Dietary AED for DM, NDF, and cell solubles were highest (P<.05) for the alfalfa hay diet. Differences between diets were minimal, indicating roughage source in 90% concentrate diets does not substantially influence milo digestion or passage as it does in 65% concentrate diets.
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Effect of roughage source on ruminal kinetics of digestion and passage of individual feed components in mixed diets for steers.Barcena-Gama, Jose Ricardo. January 1989 (has links)
Total tract digestion coefficients for dry matter (DM) and neutral detergent fiber (NDF), passage rates for grain and roughage components of diets and liquid turnover were measured for 65 and 90% concentrate diets in separate 4 x 4 Latin square experiments using intact growing steers. Kinetics of in situ digestion for DM and NDF in diet ingredients, rumen pH, volume and DM distribution were determined in mature, rumen cannulated steers. Rates of passage and digestion were combined to calculate apparent extent of ruminal digestion (AERD) for diet ingredients. Diets were based on steam flaked milo. The control roughage was chopped alfalfa hay (AH). In 65% concentrate diets, chopped wheat straw (WS), bermudagrass straw (BS) or cottonseed hulls (CSH) replaced 50% of the AH. In 90% concentrate diets, all of the AH was replaced by WS, BS or CSH. Total tract starch digestion was not influenced by source of roughage at either concentrate level. In 65% concentrate diets, total tract digestion of DM and NDF was not adversely affected by substitution of WS for 50% of the AH. Digestion of these fractions was lower (P<.05) for BS and CSH diets, but the severity of depression was greatest (P<.05) for the CSH diet. Reduced digestibility of the CSH diet was attributed to lower digestibility of CSH in comparison with AH. Although WS and BS were also less digestible than AH, their inclusion in the diet improved (P<.05) AERD of DM and NDF from milo and AH. Improved AERD for NDF appeared to be related to the raft-forming properties of WS and BS, and their ability to maintain rumen pH in a more desirable range for NDF digestion. In 90% concentrate diets, effects of roughage source on utilization of milo were minimal. Total tract digestion of DM and NDF was lower (P<.05) for WS, BS and CSH diets than for the AH diet, because of dilution of the more digestible AH by these roughages. Wheat straw had a tendency to moderate ruminal pH and consequently might be more useful in high concentrate diets than roughages such as CSH and BS.
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RUMINAL AND POSTRUMINAL UTILIZATION OF PROTEIN FROM FEED GRAINS BY STEERS.SPICER, LAWSON ALAN. January 1983 (has links)
Studies were conducted to determine the suitability of diaminopimelic acid (DAP), lysine and lysine-leucine as bacterial markers, and to compare ruminal, postruminal and total tract protein utilization and bacterial protein synthesis of sorghum grain, corn and barley based diets by beef steers. Six abomasally fistulated steers were fed 81% grain diets with 10.7% crude protein (CP) in a replicated 3 x 3 Latin square design. Diaminopimelic acid, lysine and leucine were determined in bacteria isolated from abomasal digesta (two sampling times) and rumen contents, and the ratios were used to estimate percent abomasal bacterial protein. Diaminopimelic acid concentrations in ruminal and abomasal bacteria were positively correlated (r = .40), but correlations between sample sites for lysine and leucine were essentially zero. Correlations between abomasal sampling times for the three amino acid concentrations were positive (mean r = .44). Rankings of percent bacterial protein in abomasal digesta for dietary treatments were similar based on amino acid ratio methods (DAP vs lysine vs lysine-leucine) using bacteria of rumen contents. Digestibility and bacterial synthesis data were based on lysine-leucine ratios from bacteria of rumen contents and chromium oxide ratios (digesta flow marker). Ruminal digestibilities of organic matter (OM), corrected for bacterial OM synthesis in the rumen, tended to be lower (P < .07) for sorghum grain and corn diets than for the barley diet (43, 48 vs 62%, respectively). Mean ruminal and postruminal CP digestibilities were similar (P > .05) for the three diets (-38 and 72%, respectively). Apparent total tract CP digestibility was lower (P < .05) for the sorghum grain diet than for corn or barley diets (61 vs 66 and 68%, respectively). Ruminal digestibility of feed nitrogen was lower for the sorghum grain and corn diets than for the barley diet (27 and 40 vs 69%, respectively). Percent bacterial nitrogen in the abomasum was much higher (P < .05) for the barley diet compared to the sorghum grain and corn diets (72 vs 47 and 53%, respectively). Postruminal digestibility of bacterial nitrogen was lower (P < .05) for the sorghum grain and corn diets compared to the barley diet. It is postulated that the lower apparent digestibility of sorghum grain protein in the total tract is related to a lower extent of feed protein and OM digested in the rumen.
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FACTORS AFFECTING INTAKE AND DIGESTIBILITY OF WHEAT STRAW BY STEERS.Dicko, Hamadi. January 1982 (has links)
No description available.
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Beef muscle color as affected by nutritional regime and vacuum packagingHarrison, Allen Randall January 2011 (has links)
Typescript. / Digitized by Kansas Correctional Industries
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Protein adjustment in heat-stressed finishing cattleWillms, Clifton L January 2011 (has links)
Typescript. / Digitized by Kansas Correctional Industries
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Effect of protein level, monensin and calcium:phosphorus ratio on finishing steersDurham, Susan K January 2011 (has links)
Typescript (photocopy). / Digitized by Kansas Correctional Industries
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Management of stockpiled forages and optimal use of supplements by beef cattle while consuming low-quality foragesSuverly, Norman A. 14 December 1999 (has links)
Three studies were conducted to evaluate: 1) rotationally grazed forage for late-summer stockpiling; 2) effects of lactation on self-fed supplement intake; and 3) influence of cow age on hand-fed supplement intake. For the first study, treatments consisted of non grazed, 2X and 3X grazed. Crude protein of forage grazed 3X was greater (P<.10) than non-grazed. Yield of non-grazed forage was greater (P<.10) than forage grazed 2X and 3X. Non-grazed forage displayed the greatest stockpiled yield and grazing influenced quality of stockpiled forage to a small magnitude. Treatments for the second study consisted of non, mid, and late-lactation on two experimental diets. Late-lactation cow BW change was less (P<.10) than non-lactating in both experiments and less (P<.10) than mid-lactating cows in Exp. 1 only. Forage intake for late-lactating cows was less (P<.10) than mid-lactating cows in Exp. 1 and tended to be greater (P=.13) than non-lactating cows in Exp. 2. Self-fed supplement intake was highly variable but not influenced by lactation. Treatments for the third study consisted of five age groups. In yr 1, weight change at d 57 for 11-yr cows was greater (P<.10) than 5-yr cows. In yr 2, weight change at d 28 for 8-yr cows was less (P<.10) than 4, 6, and 10-yr cows and 4-yr cows was greater (P<.10) than 6, 10, and 12-yr cows. At d 56, weight change for 4-yr cows was greater (P<.10) than 6, 8, 10 and 12-yr cows and 12-yr cows was less (P<.10) than 6 and 10-yr cows. Weight change at calving for 4-yr cows was greater (P<.10) than 6, 8, and 12-yr cows. Forage intake of 10-yr cows was greater (P<.10) than 8 and 4-yr cows. Supplement intake of 4-yr cows was greater (P>.10) than 8, 10, and 12-yr cows. Six-yr cows had greater (P<.10) supplement intakes than 12 and 8-yr cows. Three and 4-yr cows displayed the best performance and 4-yr cows consumed the greatest amount of supplement. / Graduation date: 2000
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The influence of supplemental alfalfa quality on the intake and utilization of low-quality roughages by beef cattleWeder, Christoph E. 10 May 1996 (has links)
Three experiments were conducted to evaluate the influence of quality of
supplemental alfalfa quality on beef cattle consuming low-quality meadow grass (MG)
roughages. Fifteen steers (250 kg) were assigned randomly to one of three treatments: 1)
meadow grass (5.2% CP), no supplement (MNS); 2) meadow grass plus high quality
alfalfa hay (AHS) (18.8% CP); and 3) meadow grass plus low quality alfalfa hay (ALS)
(15.2% CP). Supplements were fed at 0.45% BW and 0.55 % BW respectively. Total DM
intake was greater (P<.01) for alfalfa supplemented steers. Likewise intake of digestible
DM, DM digestibility and ruminal ammonia levels were greater for alfalfa supplemented
steers (P<.01). In Exp. 2; 96 gestating Hereford x Simmental cows (537 kg; body
condition 4.86) were assigned to the same treatments as in Exp. 1. For d-0 to d-42 cows
grazed on 19.1 ha of stockpiled MG (4539 kg/ha; 6.8% CP) whereas d-43 to d-84, cows
received MG hay (5.2% CP). Results for the 84-d study indicated that supplemented cows
gained more BW (P<.01), body condition (P<.01) and had heavier (P<.01) calf birth
weights than MNS cows. In the first 42-d period supplemented cows gained 16.2 kg more
BW than MNS cows (P<.01). Likewise, supplemented cows increased .24 BC more (P<.01) than MNS cows. The same trend was observed from d-42 to d-84, though ALS cows
lost more BC (P<.01) than the AHS cows. In Exp. 3; 90 gestating Angus x Hereford
cows (475 kg; body condition 4.59) were assigned to one of three supplemental
treatments: 1) 16.1% CP alfalfa; 2) 17.8% CP alfalfa; 3) 20.0% CP alfalfa. The level of
supplementation was 0.63%, 0.55%, and 0.50% of BW, respectively. The basal diet was
baled MG hay (5.6% CP). Weight gain and BC change for the 84-d study displayed a
quadratic response (P<.10). In conclusion, alfalfa hay is an effective way of increasing
low-quality roughage DM intake and digestibility. However, alfalfa hay quality did not
appear to dramatically effect BW, BC, and (or) calf birth weights, when fed on a
isonitrogenous basis.
(KEY WORDS: Beef cattle, Supplementation, Meadow Hay, Alfalfa Hay) / Graduation date: 1997
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