Thesis (M. App. Sc.)--University of Adelaide, Dept. of Animal Science, 1997? / Includes bibliographical references (leaves 107-130).

Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 87-92). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2002. / Typescript. Vita. Includes bibliographical references (leaves 87-92). Also available on the Internet.

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.

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

The high quality feedstuffs which are used in poultry feeds are costly and could be used directly for human food. There is less competition for fibrous feedstuffs which are less digestible by humans and other nonruminants. Feedstuffs containing crude and refined dietary fiber were examined for their effects on performance, carcass composition, crude fiber digestibility and anatomical changes of the digestive tract in growing chickens, ducklings, turkey poults and goslings. Crude fiber (CF) from dehydrated alfalfa (DA) fed to broiler chicks at 8.3 to 15% of the ration resulted in significantly reduced body weight (BW), feed consumption (FC) and feed conversion (EF). Refined fiber (RF, Cellulose) at 5 to 20% of the diet of broiler chicks resulted in significantly reduced BW and EF, while FC increased. Bacterial and enzymatic preparations added to broiler chick diets containing up to 20% RF resulted in no significant differences in BW or EF within each RF level. However, FC did not increase as RF increased. RF fed to 4 commercial broiler strain crosses resulted in no significant differences in BW, FC or EF at each level of RF. Percent carcass fat decreased in one strain and increased in all others as RF increased. Dehydrated Kentucky Bluegrass (KBG) or DA based diets fed to goslings resulted in no significant effects on mean BW. DA or KBG at 40% of the diet resulted in significantly increased FC and EF. EF of pelleted diets was better than mash diets. Mean ADF digestibility and mean carcass yields increased as DA or KBG increased in the diet. Microbial preparations (Lactobacillus sp.) fed to goslings in KBG based diets resulted in better gains and a significant improvement in EF. The addition of grit (2%) to control, DA or rye grass roughage diets resulted m no significant differences among the dietary treatments. Digestibility of ADF in chicks, poults and goslings fed diets containing 6% CF (from oat hulls, OH) increased with the level of CF. Ducklings digested no measurable amount of ADF from OH. Mean BW of chicks and ducklings fed the 6% CF diets were less, poults were unaffected, and goslings were more than those fed the control diet (C). Carcass fat pad weights in broilers were reduced, while gizzard weights increased in all species as CF increased. Ceca lengths within species did not vary; small intestines lengths decreased in chicks, ducklings, and poults, but increased in goslings as the level of CF increased in the diet. / Graduation date: 1992

Bibliography: leaves 107-130. This study evaluates quality of fermentation of the silage and also its nutritive value to ruminants on the basis of "in vitro" and "in sacco" digestability. Animal response to the silage is also evaluated in an "in vivo" digestability and nitrogen balance trial with Australian Merino sheep. The objective of this thesis is to investigate the opportunities for utilising citrus pulp and poultry litter to improve the nutritive value of wheat straw.

Thesis (MSc. (Animal Production)) -- University of Limpopo, 2016 / A study was conducted to determine the effect of shredded Colophospermum (C.) mopane wood inclusion as roughage on performance of fattening Nguni heifers weighing 200 ± 5kg. The four diets used were isocaloric and isonitrogenous but with different shredded C. mopane wood inclusion levels of 5 (F95M5), 8.5 (F91.5M8.5), 10 (F90M10) and 15 (F85M15) %. The heifers were randomly allocated to the treatments in a completely randomized design. A quadratic equation was used to determine the shredded C. mopane inclusion levels for optimal productivity of the heifers. Shredded C. mopane wood inclusion level had effect (P<0.05) on intake and feed conversion ratio (FCR). Diet DM, OM, CP, NDF and ADF intakes per metabolic weight and FCR of Nguni heifers were optimized at different shredded C. mopane wood inclusion levels of 11.0, 13.7, 8.0, 15.0, 14.0, 14.0 and 15%, respectively. However, shredded C. mopane wood inclusion level did not affect (P>0.05) diet in vitro digestibility, carcass weight, dressing percentage, meat pH, meat shear force values and meat colour intensities except for red colour intensity of rump steak. It was, thus, concluded that shredded C. mopane wood can be used as roughage without adversely affecting diet intake, FCR, and live weight of Nguni heifers. However, diet intake and FCR were optimized at different C. mopane wood inclusion levels.

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