Productive and reproductive traits in Murrah breed from Brazil

Major objective of this study was to estimate heritability and genetic correlations between milk yield (MY) and calving interval (CI) and lactation length (LL) in Murrah buffaloes using Bayesian inference. The database used belongs to the genetic improvement program of four buffalo herds from Brazil. To obtain the estimates of variance and covariance, bivariate analyses were performed with the Gibbs sampler, using the program MTGSAM. The heritability coefficient estimates were 0.28, 0.03 and 0.15 for MY, CI and LL, respectively. The genetic correlations between MY and LL was moderate (0.48). However, the genetic correlation between MY and CI showed large HPD regions (highest posterior density interval). Milk yield was the only trait with clear potential for genetic improvement by direct mass selection. The genetic correlation between MY-LL indicates that indirect selection using milk yield is a potentially beneficial strategy. The interpretation of the estimated genetic correlation between MY-CI is difficult and could be spurious.

Avaliação de genótipos de cártamo quanto ao desempenho agronômico, divergência genética e produtividade da água

Pós-graduação em Agronomia (Agricultura) - FCA

Parâmetros genéticos para características de desempenho e reprodutivas de aves poedeiras por inferência bayesiana

Pós-graduação em Genética e Melhoramento Animal - FCAV

Influence of genotype-environment interaction on the classification of Nellore bulls in Southern Brazil

The aim of this study was to assess the occurrence of genotype-environment interaction, as well as its effects on the magnitude of genetic parameters and the classification of Nellore breeding bulls for the trait adjusted weight at 205 days (W205) on Southern Brazil. The components of (co)variance were estimated by Bayesian inference, using a linear-linear animal model in a bi-trait analysis. The proposed model for the analyses considers as random the direct additive genetic and maternal effects and residual effects, and as fixed effects the contemporary groups, sex, season of birth and weighing, and calving age as covariable (linear and quadratic effects). The a posteriori mean estimates of the direct heritabilities for W205 in the three States varied from 0.24 in Paraná (PR) to 0.34 in Santa Catarina (SC). The estimates of maternal heritability varied from 0.23 in SC and Rio Grande do Sul (RS) to 0.28 in PR. The a posteriori mean distributions of the genetic correlation varied from 0.52 between SC and RS, to 0.84 between PR and RS, suggesting that the best breeding bulls in SC are not the same as in RS.

Reaction norms for the study of genotype-environment interaction for growth and indicator traits of sexual precocity in Nellore cattle

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

Productivity, stability and adaptability in open pollination progenies of Eucalyptus urophylla ST Blake

Prediction of genetic gains within breeding programs is not always compatible with those observed in practice. One reason for this inconsistency is the lack of knowledge of genotype-environment interaction (GxE). The aim of this study was to estimate genetic variation, evaluate the GxE, investigate the genetic correlation between pairs of environments and for the set, and to study the productivity, stability and adaptability at 2 years of age for diameter at breast height (DBH) in five progenies trials of Eucalyptus urophylla, used in a randomized complete block design, with the number of progenies ranging from 138 to 167, four to eight blocks and five to six plants per plot. Estimates of variance components and genetic parameters were obtained using the REML/BLUP method. For analysis of productivity, stability and adaptability, the HMRPGV method was used. The highest DBH growth was observed in Anhembi (10.52 cm) and Uberaba (10.20 cm). Estimates considered high were obtained for the coefficient of individual additive genetic variation (>13.3%) and average heritability among progenies (>0.40), indicating the possibility of obtaining genetic gains by selection among progenies. The coefficient of determination of the GxE was 1.7%, a fact that led to a high value of genotypic correlation between the performance of the progenies and environments (78.1%), indicating that the interaction is simple. The first six progenies showed a coincidence of 100% in the order of stability (HMGV), adaptability (RPGV) and productivity (HMRPGV), being 13% higher than the overall mean of five experiments (9.21 cm). When ordering the progenies, the selection of the 20 best in growth led to an increase in gain ranging of from 10.4 to 70%. Anhembi is the ideal place to have a breeding population which will be good in the other places as well.

Genotype x environment interaction for age at first calving, scrotal circumference, and yearling weight in Nellore cattle using reaction norms in multitrait random regression models

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

Estimativas dos parâmetros genéticos para seleção de árvores de Eucalyptus

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Association between ACTA1 candidate gene and performance, organs and carcass traits in broilers

This study investigates the genetic association of the SNP present in the ACTA1 gene with performance traits, organs and carcass of broilers to help marker-assisted selection of a paternal broiler line (TT) from EMBRAPA Swine and Poultry, Brazil. Genetic and phenotypic data of 1,400 broilers for 68 traits related to body performance, organ weights, weight of carcass parts, and yields as a percentage of organs and carcass parts were used. The maximum likelihood method, considering 4 analytical models, was used to analyze the genetic association between the SNP and these important economic traits. The association analysis was performed using a mixed animal model including the random effect of the animal (polygenic), and the fixed effects of sex (2 levels), hatch (5 levels) and SNP (3 levels), besides the random error. The traits significantly associated (P < 0.05) with the SNP were analyzed, along with body weight at 42 days of age (BW42), by the restricted maximum likelihood method using the multi-trait animal model to estimate genetic parameters. The analysis included the residual and additive genetic random effects and the sex-hatch fixed effect. The additive effects of the SNP were associated with breast meat (BMY), liver yield (LIVY), body weight at 35 days of age (BW35); drumstick skin (DSW), drumstick (DW) and breast (BW) weights. The heritability estimates for these traits, in addition to BW42, ranged from 0.24 ± 0.06 to 0.45 ± 0.08 for LIVY and BW35, respectively. The genetic correlation ranged from 0.02 ± 0.18 for LIVY and BMY to 0.97 ± 0.01 for BW35 and BW42. Based on the results of this study, it can be concluded that ACTA1 gene is associated with performance traits BW35, LIV and BMY, DW, BW and DW adjusted for body weight at 42 days of age. Therefore, the ACTA1 gene is an important molecular marker that could be used together with others already described to increase the economically important traits in broilers.

Parâmetros genéticos para características indicadoras de eficiência reprodutiva e produtiva de ovinos da raça Santa Inês

Pós-graduação em Genética e Melhoramento Animal - FCAV

Análise genética de escores visuais e sua relação com características reprodutivas de animais da raça Nelore

Pós-graduação em Genética e Melhoramento Animal - FCAV

Estimativas de parâmetros genéticos para características morfométricas em cavalos Quarto de Milha de Corrida

With highlighted sprint ability, the racing line is important segment within the Quarter Horses breed, with huge impact on agribusiness. Theseanimals have noted morphological differences when compared to other lines within the breed, especially for larger body size proportions.The objective of this study was to estimate genetic parameters forbody measurements traitsof the racing line of the Quarter Horses breed via Bayesian inference. Here,289 animals of both sexes, registered at brazilian association of breeders (ABQM), were used. The results showed high coefficient of heritability for body length (0.74) and back-loin lenght(0.61). The heritability coefficients for height at withersand croup length were moderate (0.44 and 0.47, respectively). High genetic correlation for body length and croup length and for body length and back-loins lengthwas also observed(0.80 and 0.76, respectively). Taking into account the estimates of heritability and genetic correlations between body measurement traits, the body length and height at withers traits proved to be appropriate to provide future researches that investigate the genetic correlation between body measurements and racing performance.

Estimativas de parâemtros genéticos para características morfométricas em cavalos Quarto de Milha de corrida

With highlighted sprint ability, the racing line is important segment within the Quarter Horses breed, with huge impact on agribusiness. Theseanimals have noted morphological differences when compared to other lines within the breed, especially for larger body size proportions.The objective of this study was to estimate genetic parameters forbody measurements traitsof the racing line of the Quarter Horses breed via Bayesian inference. Here,289 animals of both sexes, registered at brazilian association of breeders (ABQM), were used. The results showed high coefficient of heritability for body length (0.74) and back-loin lenght(0.61). The heritability coefficients for height at withersand croup length were moderate (0.44 and 0.47, respectively). High genetic correlation for body length and croup length and for body length and back-loins lengthwas also observed(0.80 and 0.76, respectively). Taking into account the estimates of heritability and genetic correlations between body measurement traits, the body length and height at withers traits proved to be appropriate to provide future researches that investigate the genetic correlation between body measurements and racing performance. Keywords: Heritability, Correlation, Length, Heigth.

Estudo do peso metabólico e índice de Kleiber na estimação de parâmetros genéticos de características ponderais em uma população de bovinos de raça brahman

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Análise multivariada de características reprodutivas e produtivas de vacas da raça Holandesa

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)