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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.
51

Desempenho, qualidade de carcaça e da carne de cordeiros alimentados com dietas contendo silagens de milho consorciadas ou não com capins tropicais /

Lopes, Keny Samejima Mascarenhas. January 2014 (has links)
Orientador: Rafael Silvio Bonilha Pinheiro / Co-orientador: Marcelo Andreotti / Banca: Viviane Corrêa Santos / Banca: Cristiano Magalhães Pariz / Resumo: O trabalho de pesquisa foi realizado com o objetivo de avaliar se há alteração no consumo, desempenho, comportamento ingestivo, digestibilidade, bem como a avaliação econômica do sistema, a qualidade da carne e característica de carcaça, dos cordeiros alimentados com dietas com silagens de milho advindas de cultivo exclusivo do milho e dos consórcios com Urochloa brizantha cv. Xaraés ou com Panicum maximum cv. Tanzânia produzidas em sistema de integração lavoura-pecuária sob plantio direto. As dietas foram compostas por 60% de volumoso e 40% de concentrado. Foram utilizados 24 cordeiros machos não castrados, 1⁄2 Dorper 1⁄2 Santa Inês, com aproximadamente 20 kg e 60 dias de idade, alojados em baias individuais com 1 m 2 . O consumo dos animais foi registrado diariamente com a obtenção do peso das sobras, onde foi permitido sobras de até 15%. Os animais foram pesados a cada 14 dias, a fim de se avaliar o desempenho, enquanto que o comportamento ingestivo foi realizado durante 24 horas, com observações a cada 5 minutos. No 14o dia do período experimental, os animais foram submetidos a coletas diárias de fezes para o ensaio de digestibilidade. A avaliação econômica utilizou como parâmetro principal a margem bruta da terminação dos cordeiros. Quando os animais atingiram o peso aproximado de 33 kg foram insensibilizados e abatidos. Durante o abate os componentes não-carcaça, assim como o sangue foram pesados para a obtenção dos rendimentos. Após o abate as carcaças foram pesadas e encaminhadas à câmara frigorífica, onde permaneceram por 24 horas. Percorrido este período as carcaças foram cortadas em meias carcaças e divididas em 5 cortes anatômicos para os cálculos de porcentagem dos cortes em relação a meia carcaça. Para as avaliações de qualidade da carne foi utilizado o músculo Longisimus lumborum, onde foi quantificada a capacidade de retenção de água, perda por cocção, cor e força de ... / Abstract: The research work was conducted to evaluate if change in intake, performance, digestibility and intake behavior, as well as the economical evaluation of confined lambs system fed diets of corn silages; exclusive cultivation of corn and intercropped with Urochloa Brizantha [syn: Brachiaria brizantha] var. Xaraés or Panicum maximum var. Tanzania; from a crop-livestock integration under no-tillage system. The diets were composed of 60% roughage and 40% concentrate. 24 non-castrated lambs were, 1⁄2 Dorper 1⁄2 Santa Ines were used, with approximately 20 kg and 60 days of age, housed in individual pens of 1 m 2 . The feed intake by the animals was recorded daily weighting of the orts, accepting 15% of orts from feed offer. The animals were weighed every 14 days in order to evaluate performance, while the intake behavior was conducted over a period of 24 h, with observations every 5 minutes. On the 14 th day of the experimental period, the animals were subjected to daily fecal sampling for the digestibility trial. The economical evaluation used as main parameter to gross margin of finishing lambs. When the animals reached the approximate body weight of 33 kg were stunned and slaughtered. During slaughtering, non-carcass components and blood were weighed to obtain yields. After slaughter, the carcasses were weighed and sent to cold storage, where they remained for 24 hours. Subsequently, the carcasses were weighed and taken to the laboratory, where they were cut into half-carcasses and divided into 5 anatomical cuts for calculations of cuts percentage in relation to the half carcasses cuts. For meat quality evaluation the Longisimus lumborum muscles were used and quantified the ability to retain water, cooking loss, color and shear force. No significant differences of treatments on weight gain and feed conversion of lambs were observed, but the highest values of consumption in kg/day, body weight and metabolic weight were provided to diets ... / Mestre
52

Studies of herbage availability and plant density in relation to animal performance

Williams, Christopher Maxwell John January 1978 (has links)
xv, 270 leaves : photos., tables, graphs ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Agronomy, 1979
53

Evaluation of tree forage as a nontraditional feedstuff for small livestock

Ayers, Anne Christine 07 August 1992 (has links)
Five experiments were conducted to evaluate tree forage as a feedstuff for small livestock, using the foliage of black locust (Robinia pseudoacacia) and hybrid poplar (Populus spp.). In the first trial, rabbits were fed diets containing 40% alfalfa (control), and 10%, 20% and 40% poplar leaves (PL) from untrimmed or uncoppiced growth, and 10% and 20% PL from trimmed or coppiced growth. At the 20% level, crude protein (CP) was better digested for the coppiced PL than for the uncoppiced (p < .05). No significant difference was evident between treatments in the average daily gain (ADG) or feed efficiency, but dry matter (DM) intake increased for all the PL treatments compared to the control (p < .01). In the second experiment, black locust (BL) leaves were treated by various methods in an attempt to counter the effect of tannins. Rabbits were fed diets containing 50% alfalfa (control), 25% alfalfa and 25% black locust meal (BLM) (BLM control), BLM + 1% polyethylene glycol (PEG), BLM + 1% phytase, and BLM + 0.3% L-methionine and 0.3% choline chloride. In general, nutrient utilization and ADG were better for the control than for the BLM treatments. The addition of PEG increased CP digestibility (p < .01) and ADF (p < .03) compared to the BLM control, partially alleviating the reduced nutrient availability. The addition of L-methionine and choline chloride increased ADF digestibility (p < .02). In the third trial, black locust (BL) bark and other tree products were used to study the possible toxic effects of lectins in BL bark. Rabbits were fed diets containing 25% BL bark, oak sawdust, red alder bark, or red alder sawdust (all diets also included 25% alfalfa). A 50% alfalfa diet served as a control. In general, nutrient digestibilities and ADG were higher for the control than the treatments and, also, higher for the BL bark diet than the alder bark diet. The ADG with the BL bark diet was lower than for the alder bark diet (p < .01), which indicated a possible toxic effect of the BL bark. The fourth trial examined the feeding value of poplar leaves for sheep. Sheep were fed diets containing 50% PL or 50% alfalfa. Nutrient digestibilities were lower for the PL diet (p < .01). In the fifth experiment, BL leaves were fed to sheep and goats in order to determine if goats, being browsers instead of grazers like the sheep, are better equipped to tolerate the anti-nutritive effects from BL forage. Sheep and goats were fed diets composed solely of BL leaves or alfalfa (control). Overall, the nutrient digestibilities were higher for alfalfa than for BL leaves, and there was no difference in terms of digestibility between species. Although the leaves of black locust and poplar contain anti-nutritive factors, it was concluded that the trees have potential as multipurpose trees from which the leaves could be harvested as animal fodder, particularly in temperate areas of the developing world. / Graduation date: 1993
54

Behavioral and physiological responses of ewes to semiconfinement and two nutritional levels in a desert climate

Gardner, Billy Wayne January 1980 (has links)
No description available.
55

A comparison of dried poultry waste, cottonseed meal and urea as nitrogen supplements for sheep fed low quality roughage

Araiza Soto, Agustin, 1951- January 1977 (has links)
No description available.
56

The influence of diet on the chemical composition of cattle and sheep : thesis submitted for the degree of Doctor of Philosophy / by Geoffrey Donald Tudor.

Tudor, G. D. (Geoffrey Donald). January 1990 (has links)
Includes bibliographical references (leaves 175-196). / xii, 196 leaves : ill. (some col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / The influence of starch in grain-based diets on fat development in cattle and sheep is investigated. / Thesis (Ph.D.)--University of Adelaide, Dept. of Animal Sciences, 1995
57

Selective grazing by sheep to improve the control of weeds of crops

Thomas, Dean Timothy January 2006 (has links)
[Truncated abstract] With the rapid development of multiple herbicide resistant weeds in crops, it is likely that an important role now exists for new grazing management strategies in farming systems to provide an integrated approach to weed management. In this thesis we examined the general hypothesis that sowing a legume of low preference by sheep relative to the target weeds of crops would improve the control of those weeds in a grazed pasture. To test this general hypothesis, legumes of low preference by Merino sheep were identified and a series of experiments conducted to determine the effect on pasture composition when these less preferred legumes were incorporated into a grazed pasture. We found a learned response that altered forage preference by sheep was important in determining the effectiveness of grazing to reduce seed set by weeds of crops. Investigations on this aspect of the grazing behaviour of sheep were a key part of this thesis. The short-term relative preference of Merino hoggets among 15 pasture legumes, 4 grain legumes and annual ryegrass was determined by offering adjacent monocultures of each of the forage genotypes to the sheep. The relative preference of the hoggets for each of the 20 forages was determined at three phases of plant growth from estimates of the amount of forage consumed. Sheep showed a low selective preference for Vetch (Vicia sativa L.), chickpea (Cicer arietinum L.), biserrula (Biserrula pelecinus L.), lotus (Lotus ornithopodioides L.) and snail medic (Medicago scutellata L.) cvs. Kelson and Sava at the vegetative phase of plant growth. An indoor method was also developed to test the relative preference of sheep among forages growing in pots. Using this method chickpea and snail medic, but not biserrula, were found to have a low relative preference by sheep at the vegetative phase.
58

Desempenho, qualidade de carcaça e da carne de cordeiros alimentados com dietas contendo silagens de milho consorciadas ou não com capins tropicais

Lopes, Keny Samejima Mascarenhas [UNESP] 03 November 2014 (has links) (PDF)
Made available in DSpace on 2015-05-14T16:53:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2014-11-03Bitstream added on 2015-05-14T16:59:26Z : No. of bitstreams: 1 000824683.pdf: 382992 bytes, checksum: 43c73d520f995e05fb7f807db6fed0c3 (MD5) / O trabalho de pesquisa foi realizado com o objetivo de avaliar se há alteração no consumo, desempenho, comportamento ingestivo, digestibilidade, bem como a avaliação econômica do sistema, a qualidade da carne e característica de carcaça, dos cordeiros alimentados com dietas com silagens de milho advindas de cultivo exclusivo do milho e dos consórcios com Urochloa brizantha cv. Xaraés ou com Panicum maximum cv. Tanzânia produzidas em sistema de integração lavoura-pecuária sob plantio direto. As dietas foram compostas por 60% de volumoso e 40% de concentrado. Foram utilizados 24 cordeiros machos não castrados, 1⁄2 Dorper 1⁄2 Santa Inês, com aproximadamente 20 kg e 60 dias de idade, alojados em baias individuais com 1 m 2 . O consumo dos animais foi registrado diariamente com a obtenção do peso das sobras, onde foi permitido sobras de até 15%. Os animais foram pesados a cada 14 dias, a fim de se avaliar o desempenho, enquanto que o comportamento ingestivo foi realizado durante 24 horas, com observações a cada 5 minutos. No 14o dia do período experimental, os animais foram submetidos a coletas diárias de fezes para o ensaio de digestibilidade. A avaliação econômica utilizou como parâmetro principal a margem bruta da terminação dos cordeiros. Quando os animais atingiram o peso aproximado de 33 kg foram insensibilizados e abatidos. Durante o abate os componentes não-carcaça, assim como o sangue foram pesados para a obtenção dos rendimentos. Após o abate as carcaças foram pesadas e encaminhadas à câmara frigorífica, onde permaneceram por 24 horas. Percorrido este período as carcaças foram cortadas em meias carcaças e divididas em 5 cortes anatômicos para os cálculos de porcentagem dos cortes em relação a meia carcaça. Para as avaliações de qualidade da carne foi utilizado o músculo Longisimus lumborum, onde foi quantificada a capacidade de retenção de água, perda por cocção, cor e força de ... / The research work was conducted to evaluate if change in intake, performance, digestibility and intake behavior, as well as the economical evaluation of confined lambs system fed diets of corn silages; exclusive cultivation of corn and intercropped with Urochloa Brizantha [syn: Brachiaria brizantha] var. Xaraés or Panicum maximum var. Tanzania; from a crop-livestock integration under no-tillage system. The diets were composed of 60% roughage and 40% concentrate. 24 non-castrated lambs were, 1⁄2 Dorper 1⁄2 Santa Ines were used, with approximately 20 kg and 60 days of age, housed in individual pens of 1 m 2 . The feed intake by the animals was recorded daily weighting of the orts, accepting 15% of orts from feed offer. The animals were weighed every 14 days in order to evaluate performance, while the intake behavior was conducted over a period of 24 h, with observations every 5 minutes. On the 14 th day of the experimental period, the animals were subjected to daily fecal sampling for the digestibility trial. The economical evaluation used as main parameter to gross margin of finishing lambs. When the animals reached the approximate body weight of 33 kg were stunned and slaughtered. During slaughtering, non-carcass components and blood were weighed to obtain yields. After slaughter, the carcasses were weighed and sent to cold storage, where they remained for 24 hours. Subsequently, the carcasses were weighed and taken to the laboratory, where they were cut into half-carcasses and divided into 5 anatomical cuts for calculations of cuts percentage in relation to the half carcasses cuts. For meat quality evaluation the Longisimus lumborum muscles were used and quantified the ability to retain water, cooking loss, color and shear force. No significant differences of treatments on weight gain and feed conversion of lambs were observed, but the highest values of consumption in kg/day, body weight and metabolic weight were provided to diets ...
59

The influence of the composition of mixed Karoo vegetation on the grazing habits of Merino and Dorper wethers

Roux, Francis Augustus January 1994 (has links)
The primary objective of this research project was to determine whether area-selective grazing, by Dorper and Merino wethers, took place in small grazing camps as governed by differences in vegetal cover. The main research techniques employed were the descending-point method for the determination of botanical composition, sub-division of the camps into gridblocks to trace sheep movement in relation to vegetation patterning, fistulated animals to determine diet selection, the electronic theodolite for micro-topography, and few minor techniques. The result have shown that area- patch- and species selective grazing are prevalent in small grazing camps under "normal" stocking densities, and that different breeds of stock (Merino and Dorper sheep) have different grazing patterns and diet selection . Climax and sub-climax areas were those primarily select ed for grazing. There is little or no correlation between botanical composition and diet selected as per fistula ted animal. The average distances travelled by Dorpers and Merinos was 2 km / day and 3.1 km/day respectively. Plant phenology did not have a detectable influence in the choice of diet.
60

Kwalitatiewe en kwantitatiewe inname van staandehooi van twee Cenchrus ciliaris kultivars (Afrikaans)

Jacobs, Salmon Stephanus 04 April 2007 (has links)
The aim of the study was to determine if significant differences, in terms of grazing parameters, intake, animal performane and digestibility, existed between foggage of Cenchrus ciliaris cv. Molopo and Cenchrus ciliaris cv. Gayndah. A grazing trial as well as a partial digestibility study was done with sheep. The following parameters were used: grazing parameters (dry matter availability and structure of the grazing), qualitative and quantitative intake, animal production and partial digestiblity. The grazing trial was conducted over two years and further divided into two separate periods of utilisation, middle and late winter. The second trial was a partial digestibility experiment conducted during the second year. In terms of the production parameters of the two varieties: dry material production and sward length of C. ciliaris cv. Molopo was constantly higher than that of C. ciliaris cv. Gayndah. In the grazing experiment the quality of selected material did not differ between C. ciliaris cv. Gayndah and Molopo. Differences in most parameters were not significant. Experimental animals grazing Gayndah selected a diet with higher N- and NDF-concentrations, as opposed to animals grazing Molopo. The same trend continued during the second year but only for N-concentration. In terms of quantitative observations in the grazing experiment the intakes of the two varieties were high for the whole duration of the trial. Only during the "out"-phase of period 1 in 1991, animals on C. ciliaris cv. Molopo couldn’t maintain an intake to meet maintenance requirements. Experimental animals gained weight in the first period of grazing of the first year of the study but not during the rest of the trial. Although intake was high in the other periods, these intakes didn’t support growth or maintenance. This suggests that supplementation in the form of a lick could address possible deficiencies. In the partial digestion trial animals grazing C. ciliaris cv. Gayndah, as opposed to animals on cv. Molopo, selected a better quality material but quantitatively there were no significant differences. For both varieties the amount of organic material consumed wasn’t adequate to meet maintenance requirements. There were no significant differences in the partial digestibility of organic material or nitrogen. Animals on both varieties were in a negative nitrogen balance. / Dissertation (MSc Agric (Animal and Wildlife Sciences))--University of Pretoria, 2007. / Animal and Wildlife Sciences / unrestricted

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