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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.
341

Produção e emissão de gases de efeito estufa de bovinos alimentados com teores de concentrado /

Estremote, Marcelo. January 2016 (has links)
Orientador: Rafael Silvio Bonilha Pinheiro / Coorientador: Marcos Chiquitelli Neto / Banca: João Batista Alves / Banca: Jane Maria Bertocco Ezequiel / Resumo: O objetivo do trabalho foi verificar a influência de teores de concentrado na emissão de metano e de dióxido de carbono, no desempenho e digestibilidade de bovinos Guzerá terminados em confinamento. Foram utilizados trinta e seis bovinos da raça Guzerá, com peso médio de 464 kg e idade de 30 meses e alojados em baias individuais de 10m2 . O delineamento experimental foi inteiramente casualizado, com três tratamentos 30, 50 e 70% de concentrado na dieta e 12 repetições por tratamento para o desempenho e digestibilidade. Para obtenção dos dados referentes à produção de metano, pH e a degradação ruminal, o delineamento foi em blocos casualizados com 3 períodos de incubação totalizando 21 repetições por ingrediente. O ganho de peso diário foi de 0,99 kg, 1,33kg e 1,22kg respectivamente, para dieta com 30, 50 e 70%, evidenciando que houve diferença (P<0,01) entre os tratamentos. O consumo de matéria seca foi menor à medida que aumentou o nível de concentrado com médias de 11,04, 10,75 e 7,67 kg/dia respectivamente para dietas com 30, 50 e 70%. A melhor conversão alimentar foi observada no tratamento de 70% de concentrado (6,73%), a qual também apresentou melhor digestibilidade entre os tratamentos. A produção de metano na dieta com 50% de concentrado apresentou as maiores médias. Na produção de gases em 12 e 24 horas foram observados que níveis maiores de concentrado apresentaram maior nível de dióxido de carbono em relação ao metano. Sendo assim as dietas com 50 e 70% de concentrado apresentaram melhor desempenho; a dieta com 70% de concentrado apresentou menor produção de metano, maior digestibilidade, menor conversão alimentar e ganho de peso em relação as dietas dos demais tratamentos / Abstract: Not available / Mestre
342

Protocolos para o uso combinado de monensina sódica e virginiamicina em dietas de bovinos Nelore confinados /

Rigueiro, André Luiz Nagatani. January 2016 (has links)
Orientador: Danilo Domingues Millen / Coorientador: Mário de Beni Arrigoni / Banca: Rafael da Costa Cervieri / Banca: Gustavo Rezende Siqueira / Resumo: O objetivo deste estudo foi avaliar o efeito do uso combinado de monensina sódica (MON) e virginiamicina (VM) sobre o desempenho produtivo, comportamento ingestivo, características de carcaça, e saúde ruminal de bovinos Nelore terminados em confinamento. Foram utilizados 72 animais machos inteiros da raça Nelore, com peso vivo médio inicial de 388±31,07 kg, provindos de sistema de recria em pasto. Os animais foram divididos em quatro tratamentos de acordo com associação ou não dos aditivos nas fases de adaptação e terminação: MON (30 mg/kg) na adaptação + terminação; MON (30 mg/kg) + VM (25 mg/kg) na adaptação e VM (25 mg/kg) na terminação; MON (30 mg/kg) + VM (25 mg/kg) na adaptação e VM (25 mg/kg) + MON (30 mg/kg) na terminação e VM (25 mg/kg) na adaptação e MON (30 mg/kg) + VM (25 mg/kg) na terminação, caracterizando assim delineamento em blocos casualizados, em que cada tratamento contou com 6 repetições (3 animais por baia, sendo as baias as unidades experimentais). A duração do experimento foi de 90 dias, sendo 19 dias de adaptação, divididos em três períodos (7, 5 e 7 dias) com dietas de 69%, 74% e 79% de ingredientes concentrados, respectivamente; e 71 dias de terminação, com dieta contendo 84% de concentrado. Durante a fase de adaptação, a suplementação somente com VM aumentou a ingestão de matéria seca em quilos (IMSKG), ingestão de matéria seca em % do peso vivo (IMSPV), diminuiu a flutuação da ingestão de matéria seca (IMS) em quilos e em porcentagem e diminui os dias para os animais atingirem 2% de IMSPV (P<0,05). No período total de confinamento, a suplementação com MON e VM na fase de adaptação e somente VM na terminação aumentou o PV final, IMSKG, IMSPV, GPD, peso de carcaça quente, área de olho de lombo (AOL) final e ganho de AOL por dia. Não houve diferenças significativas entre os tratamentos para os parâmetros relacionados a saúde ruminal e seletividade da... / Abstract: The experiment was designed to evaluate the effect of combined use of monensin (MON) and virginiamycin (VM) in the adaptation period and finishing period on feedlot performance, feeding behavior, ruminal health and carcass characteristics of Nellore cattle. Seventy two 26-mo-old yearling Nellore bulls (388±31.07 kg), backgrounded on pasture were randomly allocated and kept in 24 pens (10 m² and e 1.67 m bunk space per animal) according to the treatments: MON (30 mg/kg) in the adaptation and finishing period, MON (30 mg/kg ) + VM (25 mg/kg) in adaptation and only VM (25 mg/kg) in finish, MON (30 mg/kg) + VM (25 mg / kg) in adaptation and VM (25 mg/kg) + MON (30 mg/kg) in finish and VM (25 mg/kg) in adaptation MON (30 mg/kg) + VM (25 mg/kg) in finish, thus characterizing a completely randomized block design. Each treatment was composed by 6 replications (pens) in this study. The adaptation program consisted of ad libitum feeding of three adaptation diets over period of 19 days with concentrate level increasing from 69% to 84% of diet dry matter. During the adaptation period, animals feed with only VM showed greater dry matter intake in kilos, dry matter intake expressed as % of body weight, reduced in dry matter intake variation in kilos and percentage, and the number of days to achieve 2% of DMI, expressed as % of body weight (P<0.05). Throughout the study, steers that were fed MON and VM during the adaptation period and only VM during the finishing period increase final BW, DMI in kilograms and as percentage of BW, average daily gain, hot carcass weight, ribeye area and daily gain of ribeye area when compared to animals receiving others combinations. There were no differences between the treatments for parameters related of rumen health and selective consumption of ration (P>0.05). Thus, supplementation with only VM in the adaptation period improved the feedlot performance of the animals during the adaptation period; hovewer, the... / Mestre
343

Habitat utilization by mule deer in relation to cattle and California bighorn sheep in the Ashnola River Valley, British Columbia

Morrison, Douglas Charles January 1972 (has links)
Habitat use by mule deer, particularly in relation to use by cattle and by California bighorn sheep on the bighorn winter-spring ranges of Flatiron Mountain was studied from January 1968 through November 1969. Observations were made of (1) food habits, (2) forage production and utilization, (3) the effect of spring and summer utilization on subsequent forage production and (4) spatial and temporal distribution of range use. The results indicate that competition for forage between the native ungulates, deer and sheep, is largely obviated by differential habitat use. This may point to long term evolutionary ecological niche specialization. Some competition for forage occurs for a short period in the early spring when both ungulate species seek succulent new grass, the supply of which is at first limited. Cattle use of the winter-spring ranges was excessive and the diets of cattle and the native ungulates are similar, with the exception that utilization of grass by deer was less. Range use by cattle contributed to intra-specific cattle-deer competition on the grasslands in the spring and cattle-bighorn competition on the grasslands during the winter. The study of spring range utilization indicated that deer use was not detrimental to the 1969 annual forage production in areas used by deer. Spring range utilization by bighorn or bighorn in combination with deer reduced the standing crop of forage produced on the Agropyron spicatum dominated winter-spring ranges. Sheep utilization on South Slope during the summer, when forage growth was declining, further reduced the amount of forage available to the wintering bighorn population. / Land and Food Systems, Faculty of / Graduate
344

Effect of replacing calf starter feed with lucerne leaf-meal on diet intake, rumen degradation and growth of Holstein heifer calves

Mangena, Joyce Ledile January 2015 (has links)
Thesis (MSc. Agriculture (Animal Production)) -- University of Limpopo, 2015 / A series of experiments were carried out to investigate the effect of replacing calf starter feed with lucerne leaf-meal (LLM) on diet intake, rumen degradation and growth of Holstein heifer calves. The treatments were calf starter pellets (PEL), a mixture of 65% calf starter concentrate pellets and 35% LLM (P65L35), and a mixture of 50% calf starter concentrate pellets and 50% LLM (P50L50). The first part of the study determined nutrient composition of lucerne leaf-meal (LLM), calf starter pellets and lucerne leaf-meal substituted diets. The experimental design was a completely randomised design (CRD). Lucerne leaf-meal had high protein (25% DM) and gross energy (GE) (16.2 MJ/kg DM) levels; low starch (0.2% DM) and fibre fractions. All diets had similar (P>0.05) crude protein (CP) and GE values. The concentrate diet was higher (P<0.05) in starch, ether extracts and fibre bound CP (neutral detergent insoluble crude protein). The second part of the study estimated the supply of energy and protein fractions and carbohydrate composition from LLM and the diets. A CRD was used. Lucerne leaf-meal had high energy density and protein supply with low unavailable fibre and protein contents. All the treatments had TDN above 80%. Non-fibre carbohydrate levels differed (P<0.05) across treatments. The energy fractions were similar (P>0.05) across all dietary treatments. However, Diets P65L35 and P50L50 had higher (P<0.05) soluble and non-fibre carbohydrates than PEL diet. The third part of the study determined in vitro degradation of LLM and the three dietary treatments using the ANKOM DaisyII incubator system. Lucerne leaf-meal had high in vitro dry matter (IVDMD), organic matter (IVOMD), crude protein (IVCPD) and neutral detergent fibre (IVNDFD) degradation. All diets had similar (P>0.05) IVDMD and IVOMD at 0, 4, 10 and 48 hours of incubation. Higher (P<0.05) IVNDFD, IVCPD and effective degradation (ED) were observed in Diets P65L35 and P50L50 than in Diet PEL. No differences (P>0.05) in IVNDFD and IVCPD were observed at 24 and 48 hours of incubation. The rate of degradation (‘c’) was similar (P>0.05) across all the diets. The data demonstrated that LLM diets had higher (P<0.05) degradation values than Diet PEL. vi The fourth part of the study determined the effects of replacing calf starter pellets with lucerne leaf-meal on diet intake, feed conversion ratio and growth of pre-weaned (21 to 42 days old calves) and transition (43 to 56 days old calves) Holstein heifer calves. The experimental design was a completely randomised design, with a total of 24 calves housed in individual pens. This study was divided into two experimental phases, namely, pre-weaning (Experiment 1) and transition (Experiment 2) phases. In each experiment, different calves were used. Body weights were taken weekly. The balance of ruminal nitrogen (% RNB) was predicted using Large Ruminant Nutrition System (LRNS) model. In Experiment 1 calves had free access to clean water and fed 4 litres/calf/day of unpasteurised milk. During the pre-weaning phase, differences (P<0.05) were observed in solid feed dry matter (DM), crude protein (CP), neutral detergent fibre (NDF) and starch intakes with Diet P50L50 having higher (P<0.05) intakes than Diets PEL and P65L35. Similarly, higher (P<0.05) % RNB and daily weight gains (ADG) were observed with calves on Diet P50L50. However, calves had similar (P>0.05) initial and final weights and feed conversion ratio (FCR). Calves in Experiment 2 were fed 2 litres/calf/day of unpasteurised milk. Calves were weaned at the age of 56 days. During the transition phase, calves on Diet HP50L50 had higher (P<0.05) CP intake and % RNB than those on HPEL and HP65L35 diets. However, higher (P<0.05) solid feed starch intake was observed with calves on Diet HPEL. All dietary treatments had similar (P>0.05) DM intake, initial and final live weights, ADG and FCR. The fifth part of the study predicted diet concentrations of Holstein heifer calves under specific conditions using the level 1 solution of Large Ruminant Nutrition System (LRNS) model. During the pre-weaning phase, P65L35 and P50L50 diets indicated higher (P<0.05) energy density values than Diet PEL. However, all diets had similar (P>0.05) metabolisable energy levels. No differences (P>0.05) in net energy for maintenance (NEm) and gain (NEg) during the transition phase were observed. However, Diet HPEL had higher (P<0.05) apparent TDN and ME levels compared to other dietary treatments. Diets P65L35 and P50L50 had higher (P<0.05) protein, energy density and degradation values than Diet PEL. It is concluded LLM inclusions in the calf diet improved Holstein heifer calves’ performance. / Agricultural Research Council (ARC)
345

Effect of shredded colophospermum mopane wood inclusion as roughage on performance of fattening nguni heifers

Kgasago, Nkgaugelo January 2016 (has links)
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.
346

Effects of inoculation on alfalfa silage quality and its feeding on the performance of dairy cattle

Rizk, Charbel January 2004 (has links)
No description available.
347

The influence of alkaloids on voluntary intake and performance by ruminants fed diets containing lupin seed in Kenya

Mukisira, Ephraim Amiani January 1994 (has links)
No description available.
348

The effect of treatment of soybean meal on the availability of amino acids and the efficiency of nitrogen usage for milk production in dairy cows /

Borucki Castro, Sylvia Irene January 2007 (has links)
No description available.
349

Economic and environmental viability of substituting soybeans for lupins : the case of dairy farming in southwest Quebec

Messele, Teklay. January 1997 (has links)
No description available.
350

Fecal consistency as related to dietary composition in lactating Holstein cows

Ireland-Perry, Rebecca L. 07 April 2009 (has links)
Two trials were designed to study the relationships of dietary fiber (ADF) and protein level and source to fecal consistency in lactating cattle. In Experiment 1, 30 cows (12 multiparous, 18 primiparous) were randomly assigned to one of six total mixed diet treatments through four 21 d periods. For Experiment 2, six primiparous cows were used in two 6 x 6 Latin squares to evaluate water consumption, apparent digestibilities of DM, AOF, NOF, and starch, and to quantitate whole corn kernel passage. Total mixed diets for both trials were formulated to contain 17% (LF) or 25% AOF (HF) with CP levels of: 15% (S15) and 22% (S22) with soybean meal (SBM) supplementation, or 22% (G22) with combination of 50% corn gluten meal (eGM) and 50% SBM. Two forage sources were evaluated: corn silage (e) and alfalfa/corn silage (Ae) (50:50 on OM basis). Fecal consistency was evaluated using a 4 point scale (l-most fluid to 4-least fluid). Experiment 1 demonstrated that lower dietary fiber reduced fecal pH (LF=6.65, HF=7.11) and fecal score (LF=2.18, HF=2.41), but increased fecal DM (LF=16.1%, HF=13.2%). Supplementing SBM (S22) decreased fecal DM (S22=14.1%, G22=15.5%) and fecal score (S22=2.01, G22=2.48). Forage source affected fecal DM (C=14%,AC=15.3%), but not pH or score. HF=13.2%). Supplementing SBM (S22) decreased fecal DM (S22=14.1%, G22=15.5%) and fecal score (S22=2.01, G22=2.48). Forage source affected fecal DM (C=14%,AC=15.3%), but not pH or score. Results of Experiment 2 support major conclusions of Experiment 1. High supplementation of SBM increased daily water consumption (S22=80.2 kg, G22=74.5 kg), and reduced fecal score (S22=1.9, G22=2.4). Forage source affected apparent corn kernel (C=21.1% ,AC=33.9%) and starch (C=96%, AC=93%) digestibilities. High protein diets resulted in greater apparent DM digestibility (S15=68.2%, S22=71.8%, G22=71%). In prediction of fecal score from dietary components and animal parameters, dietary DM percent and 4% fat corrected milk (r²=.09, Experiment 1), and DM intake (r²=.12, Experiment 2) were variables most related to fecal score. Dietary effects on fecal consistency were primarily due to ADF level and type of protein supplement. Accurate prediction of fecal consistency score from the dietary and animal parameters identified was not possible. Further study is suggested to evaluate different protein sources, the contribution of water consumption, and to clarify interactions of protein, forage source and fiber level in relation to fecal consistency. / Master of Science

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