893 resultados para Carcass traits of crossbred steers surgically castrated or immunocastrated
Resumo:
The objective of this study was to evaluate the influence of inbreeding depression on traits of buffaloes from Brazil. Specifically, the traits studied were body weight at 205 and 365 days of age, average daily gain from birth to 205 days (ADG_205), average daily gain between 205 and 365 days (ADG205_365) in Mediterranean buffaloes, and milk yield, lactation length, age of first calving and calving intervals in Murrah buffaloes. Inbreeding effects on the traits were determined by fitting four regression models (linear, quadratic, exponential and Michaelis-Menten) about the errors generated by the animal model. The linear model was only significant (P<0.05) for growth traits (exception of ADG205_365). The exponential and Michaelis-Menten models were significant (P<0.01) for all the studied traits while the quadratic model was not significant (P>0.05) for any of the traits. Weight at 205 and 365 days of age decreased 0.25kg and 0.39kg per 1% of increase in inbreeding, respectively. The inbred animals (F=0.25) produced less milk than non-inbred individuals: 50.4kg of milk. Moreover, calving interval increased 0.164 days per 1% of increase in inbreeding. Interestingly, inbreeding had a positive effect on age at first calving and lactation length, decreasing age of first calving and increasing lactation length. © 2012 Japanese Society of Animal Science.
Resumo:
The goal of this study was to evaluate the effects of different soybean oil availabilities on the intake and partial and total digestibility of dry matter (DM) and nutrients, rumen fermentation parameters, efficiency of microbial synthesis, and the rumen microbiota of crossbred beef heifers. Nine crossbred heifers fitted with rumen and duodenal cannulae were evaluated in a triple 3 × 3 Latin square design with three treatments and three periods in three simultaneous repetitions. Heifers approximately 18 months old, with mean initial and final body weights of 316.3±28.8 and 362.6±34.4 kg, respectively, were fed a diet containing 600. g/kg of corn silage and 400. g/kg concentrate with a 58.0. g/kg fat content in the total diet. The sources of lipids included soybean grain, rumen-protected fat, and soybean oil. The statistical analyses were conducted using PROC MIXED from SAS, and the means were compared using Tukey's test (P<0.05). Dietary lipid sources did not affect nutrient intake (P>0.05). Except the apparent digestibility of organic matter (P=0.024), the apparent digestibility of the other nutrients did not differ among the treatment groups. Regarding body nitrogen retention, the soybean grain treatment was more effective than the rumen-protected fat treatment (P=0.045); however, the soybean oil treatment did not differ from the other two treatments. In relation to the efficiency of microbial protein synthesis (g. N/kg of organic matter apparently digested in the rumen corrected for microbial organic matter), the soybean oil and soybean grain treatments were more efficient than the rumen-protected fat treatment (P=0.001). Animals fed rumen-protected fat had larger numbers of protozoa (P<0.001) and fungi (P<0.001) than those supplemented with soybean grain and soybean oil. The dietary lipid sources did not affect pH, the molar concentration of propionate and total volatile fatty acids (P>0.05), whereas the concentrations of ammonia nitrogen and acetate were higher in animals fed with rumen-protected fat than in those submitted to the other treatments. The use of different soybean oil availabilities did not affect nutrient intake; however, treatments with soybean oil and soybean grain were more efficient regarding nutrient intake than rumen-protected fat because they reduced the numbers of fungi and protozoa and consequently improved the efficiency of microbial protein synthesis. © 2013 Elsevier B.V.
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
The gene responsible for coding the leptin hormone has been associated with productive and reproductive traits in cattle. In dairy cattle, different polymorphisms found in the leptin gene have been associated with several traits of economic interest, such as energy balance, milk yield and composition, live weight, fertility and dry matter consumption. The aim of this study was to detect genetic variability in the leptin gene of buffaloes and to test possible associations with milk yield, fat and protein percentages, age at first calving and first calving interval. Three genotypes (AA, AG and GG) were identified by polymerase chain reaction-restriction fragment length polymorphism, which presented genotypic frequencies of 0.30, 0.54 and 0.16, respectively. The allele frequencies were 0.57 for the A allele and 0.43 for the G allele. No significant effects were found in the present study, but there is an indicative that leptin gene affects lipid metabolism. © 2013 Springer Science+Business Media Dordrecht.
Resumo:
Contents: The osteopontin gene may influence the fertility of water buffaloes because it is a protein present in sperm. The aim of this work was to identify polymorphisms in this gene and associate them with fertility parameters of animals kept under extensive grazing. A total of 306 male buffaloes older than 18 months, from two farms, one in the state of Amapá and the other in the state of Pará, Brazil were used in the study. Seven SNPs were identified in the regions studied. The polymorphisms were in gene positions 1478, 1513 and 1611 in the region 5′upstrem and positions 6690, 6737, 6925 and 6952 in the region amplified in intron 5. The SNPs were associated with the traits, namely scrotal circumference, scrotal volume, sperm motility, sperm concentration and sperm pathology. There were significant SNPs (p < 0.05) for all the traits. The SNP 6690 was significant for scrotal circumference, sperm concentration, sperm motility and sperm pathology and the SNP 6737 for scrotal volume. The genotype AA of SNP 6690 presented the highest averages for scrotal circumference, sperm concentration and motility and the lowest total number of sperm pathologies. For the scrotal volume trait, the animals with the largest volume were correlated with the presence of the genotype GG of SNP 6737. These results indicate a significance of the osteopontin gene as it seems to exert a substantial influence on the semen production traits of male buffaloes. © 2013 Blackwell Verlag GmbH.
Resumo:
Pós-graduação em Zootecnia - FCAV
Resumo:
Pós-graduação em Zootecnia - FMVZ
Resumo:
A mandioca é cultivada como "mandioca mansa" para consumo in natura e "mandioca para indústria" como fonte de amidos e farinhas. Raças locais foram utilizadas para descoberta de "mutações espontâneas" e desenvolvimento de abordagem evolutiva e de melhoramento para estudos de função gênica. Recursos de Genômica e Proteômica foram obtidos. Análises de expressão gênica por blot de RNA e microarranjos foram desenvolvidos para identificação de expressão diferencial. "Mandioca açucarada" foi identificada, sendo relacionada com falta de expressão do gene da BEI e de uma mutação "nonsence" na sequência do gene GBSSI causando a formação do amido serose. "Mandioca avermelhada" apresentou falta de expressão do gene CasLYB, e a "amarela" uma regulação de repressão do gene CasHYb. Análise Proteômica do complexo carotenóide-proteína, juntamente com a análise de expressão de gene da CAP4, revelaram uma dupla fita de cDNA associada ao elevado acúmulo de carotenóide. Sequenciamento do gene da GBSSI identificou 22 haplótipos e grande diversidade de nucleotídios. Populações segregantes de cruzamentos de fenótipos bioquímicos diferenciados com cultivares elites dos Cerrados foram obtidas.
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Pós-graduação em Zootecnia - FMVZ
Resumo:
The aim of this study was to estimate genetic, environmental and phenotypic correlation between birth weight (BW) and weight at 205 days age (W205), BW and weight at 365 days age (W365) and W205-W365, using Bayesian inference. The Brazilian Program for Genetic Improvement of Buffaloes provided the data that included 3,883 observations from Mediterranean breed buffaloes. With the purpose to estimate variance and covariance, bivariate analyses were performed using Gibbs sampler that is included in the MTGSAM software. The model for BW, W205 and W365 included additive direct and maternal genetic random effects, maternal environmental random effect and contemporary group as fixed effect. The convergence diagnosis was achieved using Geweke, a method that uses an algorithm implemented in R software through the package Bayesian Output Analysis. The calculated direct genetic correlations were 0.34 (BW-W205), 0.25 (BW-W365) and 0.74 (W205-W365). The environmental correlations were 0.12, 0.11 and 0.72 between BW-W205, BW-W365 and W205-W365, respectively. The phenotypic correlations were low for BW-W205 (0.01) and BW-W365 (0.04), differently than the obtained for W205-W365 with a value of 0.67. The results indicate that BW trait have low genetic, environmental and phenotypic association with the two others traits. The genetic correlation between W205 and W365 was high and suggests that the selection for weight at around 205 days could be beneficial to accelerate the genetic gain.
Resumo:
Quantitative analysis of growth genetic parameters is not available for many breeds of buffaloes making selection and breeding decisions an empirical process that lacks robustness. The objective of this study was to estimate heritability for birth weight (BW), weight at 205 days (W205) and 365 days (W365) of age using Bayesian inference. The Brazilian Program for Genetic Improvement of Buffaloes provided the data. For the traits BW, W205 and W365 of Brazilian Mediterranean buffaloes 5169, 3792 and 3883 observations have been employed for the analysis, respectively. In order to obtain the estimates of variance, univariate analyses were conducted using the Gibbs sampler included in the MTGSAM software. The model for BW, W205 and W365 included additive direct and maternal genetic random effects, random maternal permanent environmental effect and contemporary group that was treated as a fixed effect. The convergence diagnosis was performed employing Geweke, a method that uses an algorithm from the Bayesian Output Analysis package that was implemented using R software environment. The average values for weight traits were 37.6 +/- 4.7 kg for BW, 192.7 +/- 40.3 kg for W205 and 298.6 +/- 67.4 kg for W365. The heritability posterior distributions for direct and maternal effects were symmetric and close to those expected in a normal distribution. Direct heritability estimates obtained using the modes were 0.30 (BW), 0.52 (W205) and 0.54 (W365). The maternal heritability coefficient estimates were 0.31, 0.19 and 0.21 for BW, W205 and W365, respectively. Our data suggests that all growth traits and mainly W205 and W365, have clear potential for yield improvement through direct genetic selection.
Resumo:
The objective of the study was to estimate heritability and repeatability for milk yield (MY) and lactation length (LL) in buffaloes using Bayesian inference. The Brazilian genetic improvement program of buffalo provided the data that included 628 females, from four herds, born between 1980 and 2003. In order to obtain the estimates of variance, univariate analyses were performed with the Gibbs sampler, using the MTGSAM software. The model for MY and LL included direct genetic additive and permanent environment as random effects, and contemporary groups, milking frequency and calving number as fixed effects. The convergence diagnosis was performed with the Geweke method using an algorithm implemented in R software through the package Bayesian Output Analysis. Average for milk yield and lactation length was 1,546.1 +/- 483.8 kg and 252.3 +/- 42.5 days, respectively. The heritability coefficients were 0.31 (mode), 0.35 (mean) and 0.34 (median) for MY and 0.11 (mode), 0.10 (mean) and 0.10 (median) for LL. The repeatability coefficient (mode) were 0.50 and 0.15 for MY and LL, respectively. Milk yield is the only trait with clear potential for genetic improvement by direct genetic selection. The repeatability for MY indicates that selection based on the first lactation could contribute for an improvement in this trait.
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)