Estimation of heritability for early weights in Santa Inés sheep from Brazil and Colombia

Abstract

Knowing the heritable fraction of productive traits, such as birth weight and weaning weight, is an indispensable tool for selecting animals with higher genetic merit, facilitating decision-making in crossbreeding programmes. This study aimed to genetically evaluate populations of Santa Inés sheep in Brazil and Colombia using Bayesian inference analysis. The study was conducted using information from three sheep farms. The first was located in the Municipality of La Ceja, Antioquia (Colombia), the second in the municipality of Barbosa, Antioquia (Colombia), and the third in the municipality of Campo Santana (Brazil). The model included the additive genetic effect and maternal genetic effect, and considered sex, delivery type, and contemporary group as fixed effects. Components of variance and genetic parameters were estimated. The mean and standard deviation for birth weight (BW) and weaning weight adjusted to 90 days (WW90) were 3.36 kilograms (kg) ± 0.8 and 3.19 kg ± 0.861 for Brazil, and 7.76 kg ± 4.76 and 20.18 kg ± 5.31 for Colombia. The mean of direct heritability (h²d) of BW and WW90 was 0.31 and 0.27 for Brazil, and 0.61 and 0.30 for Colombia. It can be concluded that it is essential to keep accurate records at all sheep farms to ensure a good selection of animals for breeding programmes, to ensure animals with greater genetic and productive potential.