Parâmetros genéticos do peso ao nascer de dois rebanhos ovinos criados no Rio Grande do Sul

Abstract

Obtaining estimates of genetic values for the characteristics of economic interest is of great importance for any production system, providing better planning in the matings due to knowing and obtaining objective selection indexes. In view of this, the development of genetic improvement programs for production species is limiting to the progress of the system. In Rio Grande do Sul the main carrying characteristic is birth weight, studies show that this characteristic is subject to the influence of genetic and environmental factors, making it possible to select animals using it. In this sense, the present study aimed to estimate genetic parameters for birth weight in two sheep herds raised in Rio Grande do Sul. Information on birth weight of two different sheep herds, called Fazenda 1 and Fazenda 2, was used. 1, information on animals of the Texel breed, where 575 were lambs, born between the years 2014 and 2016, children of 17 sheep and 202 sheep, distributed in 9 GC, from the city of Bagé - RS. Fazenda 2, animals produced by crossing F1 Finnish Landrace X Frisona Milchschaf sheep with Polwarth sheep, which held information on 1,234 lambs, born between the period 2012 to 2016, children of 11 sheep and 652 sheep, distributed in 38 GC, from 38 GC of the municipality of Herval - RS. The statistical model defined by AMARILHO-SILVEIRA et al. (2018). To obtain the components of variances and genetic parameters, a single-characteristic analysis was performed using the Bayesian method and using a Gibbs sampler, with the aid of the GIBBS2F90 program (MISZTAL et al., 2002). At Fazenda 1, it is noted that direct heritability had a low magnitude (0.10 ± 0.08), another relevant point to be identified is maternal heritability, which showed moderate magnitude (0.26 ± 0.11). In Fazenda 2, maternal heritability showed a high magnitude (0.48 ± 0.14), and in this same sense there is direct heritability that showed high expression (0.46 ± 0.19).