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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Accuracy and precision of a microscopic technique for estimating species composition of in vitro digested mixtures

Dembele, Digo January 1981 (has links)
No description available.
22

NON-PROTEIN NITROGEN AND AMINO ACID UTILIZATION BY POULTRY

Frederick, Howard Massey, 1941- January 1974 (has links)
No description available.
23

Evaluation of nutrient intake and digestion in grazing sheep receiving supplements : thesis submitted for the degree of Doctor of Philosophy / by Brenton John Hosking

Hosking, Brenton John January 1987 (has links)
Includes bibliographical references (leaves 290-309) / 310 leaves : ill ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / 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. / Thesis (Ph.D.)--University of Adelaide, Dept. of Animal Sciences, 1987
24

Restricted feeding and the functional efficiencies of the laying hen / by P.C. Glatz

Glatz, Philip C. January 1980 (has links)
Typescript (photocopy) / Includes bibliographical references (leaves 223-249) / 249 leaves, [10] leaves of ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Investigates the relationship between feed conversion efficiency and physiological variables among several lines, generations and breeds of hen fed ad libitum or on restricted amounts of feed; and, of the consequences to egg shell quality of restriction of food supplied to laying hens. / Thesis (Ph.D.)--University of Adelaide, Dept. of Animal Physiology, 1982
25

Restricted feeding and the functional efficiencies of the laying hen / by P.C. Glatz

Glatz, Philip C. January 1980 (has links)
Typescript (photocopy) / Includes bibliographical references (leaves 223-249) / 249 leaves, [10] leaves of ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Investigates the relationship between feed conversion efficiency and physiological variables among several lines, generations and breeds of hen fed ad libitum or on restricted amounts of feed; and, of the consequences to egg shell quality of restriction of food supplied to laying hens. / Thesis (Ph.D.)--University of Adelaide, Dept. of Animal Physiology, 1982
26

Nitrogen use efficiency of dried distillers grains and nitrogen fertilizer in forage based livestock production systems

Greenquist, Matthew A. January 1900 (has links)
Thesis (Ph.D.)--University of Nebraska-Lincoln, 2008. / Title from title screen (site viewed Oct. 21, 2008). PDF text: viii, 129 p. : ill. ; 696 K. UMI publication number: AAT 3308320. Includes bibliographical references. Also available in microfilm and microfiche formats.
27

The determination of dry matter digestibility of Atriplex nummularia cv. De Kock with different techniques

Van der Baan, Annelize. January 2008 (has links)
Thesis (M.Sc.(Agric)(Animal Nutrition)) -- University of Pretoria, 2008. / Summary in English. Includes bibliographical references.
28

Effect of dietary inclusion of Moringa oleifera Lam leaf meal on feed conversion efficiency, meat quality, fatty acid composition, shelf life and consumer health-related perceptions of pork

Mukumbo, Felicitas Esnart January 2013 (has links)
The objective of the study was to determine the feed conversion efficiency (FCE), carcass characteristics, physico-chemical quality, fatty acid (FA) composition and shelf life of pork from pigs fed diets containing either 0% (T1), 2.5% (T2), 5% (T3) or 7.5% (T4) Moringa oleifera leaf meal (MOLM). Consumer health-related perceptions on pork and fatty acids were also investigated. Twenty four crossbred Large White x Landrace pigs of both sexes at 18 weeks of age and initially weighing 71.6 kg on average were housed individually and had ad libitum access to one of the four dietary treatments for a period of six weeks. Average daily feed intake (ADFI) and average daily gain (ADG) and feed conversion ratios (FCR) were calculated as an indication of FCE and pigs were slaughtered at an average live weight of 99.6 kg. Carcass traits such as back fat thickness (BFT), carcass temperatures and pH readings taken 45 minutes and 24 hours (pH45 and pHu) post mortem were recorded. M. longissimus thoracis et lumborum (LTL) samples were taken from each carcass for the determination of lightness (L*), redness (a*), yellowness (b*), thawing loss percentage (TL%), cooking loss percentage (CL%), Warner Bratzler Shear Force (WBSF), shelf life and FA composition. Furthermore a survey was conducted amongst 80 University of Fort Hare Students to determine their health-related perceptions on pork and fatty acids as well as their pork consumption frequency using questionnaires. The FCE of pigs fed on 0-5% MOLM (T1, T2 and T3) diets did not differ significantly, but the FCE of pigs fed 7.5% MOLM (T4) was significantly (p<0.05) reduced. No significant relationship was reported between inclusion of MOLM carcass characteristics and physico-chemical pork quality. There was however a significant improvement (p<0.05) in the shelf life of the pork from MOLM fed pigs in terms of colour and odour during 10 days of refrigerated storage (at 3±1°C). There was a significant (p<0.05) reduction in the total intramuscular fat (IMF) content and the saturated fatty acid (SFA) C18:0 (stearic acid) content and an overall non-significant (p>0.05) increase in the poly unsaturated fatty acid (PUFA) content of pork from MOLM fed pigs. The possible reason for this is that the feeding of MOLM was commenced when the pigs were at an advanced age and weight. The survey revealed that the majority of interviewed students consume fresh (39.7%) and processed (32.4%) pork two to three times a week, perceive pork to be generally healthy (70%) and the second most healthy meat type (39.5%). While the majority (55.4%) were aware of the health implications of FAs they did not know which FA classes pose more of a health risk (51.3%). In conclusion2.5% and 5% of MOLM in finisher pig feed did not negatively affect FCE, carcass characteristics or physico-chemical meat quality; significantly improved pork shelf life and reduced total IMF and SFA content of pork but 7.5% MOLM negatively affected FCE; and the majority of students perceive pork to be the second most healthy type of meat and are generally aware of the health implications of FAs.
29

Evaluation of dietary carbohydrate utilization by captive sablefish (Anoplopoma fimbria)

Walsh, Mark Gordon January 1991 (has links)
Carbohydrates have variable digestibilities and metabolizable energy values in carnivorous fish. Simple sugars are generally more digestible than complex polysaccharides, and low levels of dietary carbohydrate may contribute more metabolizable energy than high levels. Two experiments were conducted to study the effects of dietary level and processing treatment of wheat starch on the digestibility of diets fed to sablefish (Anoplopoma fimbria), in different regions of the digestive tract. Moreover, an experiment was undertaken to determine if the dietary concentration of an indigestible external marker (chromic oxide) influenced its motility, relative to other ingredients in the ingesta, as it passed through the digestive tract. Lastly, a growth experiment was undertaken to compare the performance of sablefish fed formulated diets containing one of two levels of carbohydrate to that of fish fed a natural fish diet. The gastric evacuation of a formulated and a natural diet were also investigated. Apparent digestibility values for the nutrients in a formulated diet (containing 44.4% cooked wheat and 0.1% chromic oxide) fed to sablefish were noted to increase progressively from the anterior to the posterior regions of the intestinal tract. Within each region of the gut, the apparent digestibility values for most nutrients declined over three sample periods. Carbohydrate (nitrogen-free extract) digestibility down to the distal section of the intestine ranged from 51.0 to 82.8%. An experiment designed to assess the effect of carbohydrate treatment on the digestibility of four isonitrogenous, isocaloric diets met with partial failure. It was determined that the 1.0% chromic oxide marker flowed at a differential rate to the rest of the ingesta in the digestive tract, which violated the criteria for an effective marker. Consequently, diet digestibility was not determined in this experiment. Hepatic glycogen levels in fish receiving the dietary treatments were compared, and these values were used to estimate the relative availability (digestibility) of carbohydrate from the respective diets. According to this index, the sequence for digestibility was as follows: pregelatinized starch > cooked wheat > pregelatinized starch/cooked wheat > unprocessed wheat. Differential movement of chromic oxide relative to other ingesta was observed in sablefish fed on alternate days regardless of the dietary concentration of the indigestible marker (0.1 or 1.0%). It was surmised that the feeding protocol established the circumstances from which marker 'streaming' was observed in the results. Differential transport of Cr₂O₃ through the gut by ingested seawater was suggested as a possible mechanism for the phenomenon. Sablefish fed a natural fish diet had the highest growth rates, condition factors, liver lipid levels and the lowest feed conversion ratios and liver glycogen levels. Sablefish fed a diet containing 22.2% cooked wheat had a higher growth rate, condition factor, and a lower food conversion ratio, than those fed a diet containing 44.4% cooked wheat. Ingestion of the 44.4% cooked wheat diet resulted in the highest values for liver glycogen and hepatosomatic index. It was concluded that sablefish have a limited ability to metabolically utilize digestible carbohydrate and that most of the dietary non-protein energy should originate from high quality lipid for maximum protein sparing. / Science, Faculty of / Resources, Environment and Sustainability (IRES), Institute for / Graduate
30

The effect of formaldehyde treatment of the forage portion of the diet, the addition of branched-chain volatile fatty acids and/or sulphur on the utilization of nitrogen and carbohydrate by sheep

Tuah, Ambrose Kwame January 1978 (has links)
Formaldehyde treatment of dietary protein to reduce its degradation in the rumen has been reported to be beneficial in some instances. Four levels of formaldehyde (0.0%, 0.8%, 1.0% and 1.2% on an air dry basis) were applied to a dehydrated and hammermilled grass-clover forage. In vitro nitrogen digestibility and ammonia-nitrogen production at *the microbial stage of incubation were reduced significantly (p < 0.05) as the level of formaldehyde was increased. Nitrogen digestibility for the combined microbial and acid-pepsin stages of incubation was significantly (p < 0.05) reduced only at the 1.2% level of formaldehyde application compared to the untreated forage. Ram lambs ranging in body weights of 29kg to 36kg were then used in studies of nitrogen and carbohydrate metabolism. One percent formaldehyde was applied to the grass-clover forage. Each of the five diets (14% C.P. on D.M. basis) contained 50% grass-clover forage, 38% cassava, 11% barley and 1% sheep mineral premix on a dry matter basis. Diet one contained the untreated forage while the others contained the formaldehyde treated forage. Diets three and five were supplemented with isovaleric acid (3.0g/Kg diet) and isobutyric acid (2.3g/Kg diet). Diets four and five were supplemented with sulphur in the form of sodium sulphate. The apparent digestibility coefficients of acid-detergent fibre and cellulose were increased significantly (p < 0.05) by formaldehyde treatment of the forage. The apparent digestibility coefficient of nitrogen was significantly (p < 0.05) depressed by formaldehyde treatment of the forage except for the diet supplemented with VFAS (diet three). The apparent digestibility coefficients of dry matter and organic matter were not affected significantly (p > 0.05). Ruminal fluid levels of isovaleric and isobutyric acids were significantly (p < 0.05) higher for animals fed diet three than for animals fed diets two and four. Formaldehyde treatment of the forage resulted in significantly (p < 0.05) higher levels of valeric acid and lower levels of ammonia in ruminal fluid. Ruminal fluid levels of total volatile fatty acids, acetic, propionic and butyric acids and rumen pH were not affected significantly (p < 0.05) by formaldehyde treatment of the forage. The ratio of microbial protein-nitrogen (estimated from RNA-N) to total abomasal digesta nitrogen was significantly (p < 0.05) decreased by formaldehyde treatment of the forage except for the diet supplemented with VFAS (diet three). The concentration of non-protein-nitrogen in abomasal digesta was significantly (p < 0.05) reduced by formaldehyde treatment of the forage. Abomasal digesta pH, concentration of total nitrogen, RNA-N, microbial protein-nitrogen, acid-detergent fibre, and cellulose were not affected. The reduction in the ratio of microbial protein-nitrogen to total abomasal digesta nitrogen and non-protein-nitrogen by formaldehyde treatment of the forage suggests that the treatment reduced microbial degradation of dietary protein except perhaps for the diet supplemented with VFAS (diet three). Nitrogen balance was significantly (p < 0.05) improved by formaldehyde treatment of the forage except for the sulphur supplemented diets. Sulphur supplementation tended to offset the beneficial effects of formaldehyde protection of the forage protein. Supplementation with VFAS did not further enhance nitrogen utilization. Formaldehyde treatment of the forage significantly (p < 0.05) improved sulphur balance except for the diet supplemented with both sulphur and VFAS (diet five). Daily feed intake and urine output per unit metabolic body size and growth rate over a seventeen-day period were not significantly (p < 0.05) affected by formaldehyde treatment of the forage. The flow of total digesta, organic matter, dry matter, acid-detergent fibre, cellulose and total nitrogen through the duodenum for a 24-hour period was markedly higher for the diets containing the formaldehyde treated forage. The flow of microbial protein-nitrogen and non-protein-nitrogen however was markedly depressed by formaldehyde treatment of the forage. A sheep fitted with a duodenal re-entrant cannula was used for this study. / Land and Food Systems, Faculty of / Graduate

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