Effect of glycerol on the viability and fertility of cooled bovine semen

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Accuracy of genotype imputation in Nelore cattle

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The Genetic Architecture of Climatic Adaptation of Tropical Cattle

Adaptation of global food systems to climate change is essential to feed the world. Tropical cattle production, a mainstay of profitability for farmers in the developing world, is dominated by heat, lack of water, poor quality feedstuffs, parasites, and tropical diseases. In these systems European cattle suffer significant stock loss, and the cross breeding of taurine x indicine cattle is unpredictable due to the dilution of adaptation to heat and tropical diseases. We explored the genetic architecture of ten traits of tropical cattle production using genome wide association studies of 4,662 animals varying from 0% to 100% indicine. We show that nine of the ten have genetic architectures that include genes of major effect, and in one case, a single location that accounted for more than 71% of the genetic variation. One genetic region in particular had effects on parasite resistance, yearling weight, body condition score, coat colour and penile sheath score. This region, extending 20 Mb on BTA5, appeared to be under genetic selection possibly through maintenance of haplotypes by breeders. We found that the amount of genetic variation and the genetic correlations between traits did not depend upon the degree of indicine content in the animals. Climate change is expected to expand some conditions of the tropics to more temperate environments, which may impact negatively on global livestock health and production. Our results point to several important genes that have large effects on adaptation that could be introduced into more temperate cattle without detrimental effects on productivity.

Finishing precocity visual score and genetic associations with growth traits in Angus beef cattle

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influência da imunocastração (Bopriva®) no ganho de peso, características de carcaça e qualidade da carne de bovinos Nelore

The objective of this study was evaluate the effects of immunocastration on body weight gain, carcass characteristics and meat quality of Nellore beef cattle. Eighty Nellore beef cattle, with initial body weight of 357 +/- 8.63 kg, were placed in feedlots and distributed in two treatments (40 animals per treatments) as follow: one - non-vaccinated bulls and two - immunocastrated bulls (Bopriva (R), Pfizer Animal Health). The animals placed on treatment two were vaccinated in two doses, first application 30 days before they arrive on the feedlots and second on the day they arrive on feedlots. After 67 days of experimental period, was calculated the daily gain of live weight in kg/day of the 80 animals and selected 20 animals from each treatment for the slaughter and carcass evaluations, and ten from each group for the meat analyzes. The data were submitted to analysis of variance. Immunocastrated animals showed lower daily weight gain, hot carcass weight, carcass yield, pH, leg thickness, muscle depth, loin muscle area, carcass muscle percentage, shear force and moisture. However, this animals had higher concentration of lactate and cortisol blood, chest depth, fat thickness, finishing degree, a *, b * and c*, liquid loss in thawing process, myofibrillar fragmentation index and ether extract of meat when compared to non-vaccinated bulss. The immunocastration (Bopriva (R)) is an alternative for improving the quality of meat by the higher fat deposition and by the reduction of the shear force of the meat when compared to non-vaccinated bulls.

Ácidos graxos da gordura de cobertura do contrafilé de bovinos Nelore e Canchim terminados em confinamento e alimentados com diferentes níveis de concentrado nas dietas

The objective was to evaluate fatty acids composition of the back fat in loin meat (Longissimus muscle) from Nellore and Canchim young bulls. The animals were finished at feedlot and received sugar cane diets with two concentrate levels (40 and 60% of dry matter). The concentrates were formulated with sunflower grains, corn, soybean meal, dry sugar cane yeast, urea and mineral mixture. The experimental design was a completely randomized design with a 2x2 factorial arrangement (genetic group x concentrate level), and the results were submitted to the variance analysis and means compared by Tukey test at 5% probability, when the interaction was significant. The loin backfat of Nellore bulls had higher concentration of conjugated linoleic acids than Canchim bulls (0.86 and 0.59%, respectively). On the other hand, the loin back fat of Canchim bulls had higher concentrations of estearic (17.07%) and linoleic acids (2.40%) and polyunsaturated fatty acids than Nellore bulls, that showed values of 13.47 and 1.44%, respectively. The Nellore and Canchim loin back fat presents significant amounts of beneficial fatty acids to human health. Levels of 40 and 60% of concentrate in the diet did not alter the fatty acids composition of loin backfat.

Análise de componentes principais para características de crescimento em bovinos de corte

The objetive of this research was to study the relation among body weight and average daily gain in different ages, using principal components analysis. Data on 1663 birth weight (BW), weaning weight adjusted to 230 days (WW), yearling weight adjusted to 365 days (YW), long yearling weight adjusted to 550 days (LYW), average daily gain from birth to weaning (AGW), average daily gain from weaning to 365 days (AGY) and average daily gain from 365 days weight to 550 day weight (AGL) from crossbred animals, and data on 320 observations of the same traits from straightbreed Nellore animals were analysed. The model included the fixed effects of breed (only crossbred data), contemporary group, and linear and quadratic effects of age at calving. For body weight in different ages, the first principal component contrasted heavier and light animals after birth and explained about 79,0% and 78,0% of the variation for data on crossbred and Nellore animals, respectively. The second principal component compared heavier animals at weaning and yearling weight those at long yearling weight. It explained around 13,5% and 15,5% of the total variation, respectively, for data on F1 and Nellore breed. The major source of variation among animals on the two data set for body weight was due to differences in weight followed by differences in the ages they got those weight. For the traits expressed as average daily gain, the variation among animals was due to differences in birth season, the first principal component explaining about 52,0% of the variation on crossbred animals. This component compared animal with higher AGY with those with higher AGW and AGL. For data on Nellore breed, the first component explain about 56,0% of the total variation and also compared animals with higher AGY with those with higher AGW and AGL.

Morfometria e compactação da cromatina espermática de touros Nelore de acordo com a idade e sua influência na produção de embriões in vitro

Pós-graduação em Medicina Veterinária - FCAV

Termografia e ultrassonografia Doppler do plexo pampiniforme e termografia do escroto de touros: correlação com a qualidade do sêmen

Pós-graduação em Medicina Veterinária - FCAV

Avaliação física e radiográfica dos carpos, tarsos e articulações interfalangeanas de touros de raças zebuínas em regime de colheita de sêmen

Pós-graduação em Medicina Veterinária - FCAV

Seleção genômica para características de carcaça em bovinos da raça Nelore

Pós-graduação em Genética e Melhoramento Animal - FCAV

Utilizações de informações genômicas para o melhoramento genético de características de crescimento em bovinos da raça Nelore

Pós-graduação em Genética e Melhoramento Animal - FCAV

Crude glycerin in the supplement for beef cattle on pasture

Pós-graduação em Zootecnia - FCAV

Different sources of forage with crude glycerin in diets with higher percentage of concentrate to beef cattle

Pós-graduação em Zootecnia - FCAV

Desempenho de bovinos cruzados e parâmetros qualitativos de músculos maturados

Pós-graduação em Zootecnia - FCAV