Genetic Analysis of Meat-Type Quail Growth Under Different Nutritional Environments

Our objectives was to evaluate a two-step approach to further investigate the presence of genotype by environment interaction in growth curves. Body weight from 2,274 quails from UFV1 and UFV2 lines in ten crude protein levels (24-33%) were used. Animals were weighed weekly from hatch to 42 days old totalizing up to seven records. The parameters from Gompertz model were used as phenotypes in a reaction norm model. Reaction norm covariate was based on protein level estimates from a conventional animal model. Genetic values reaction norms, heritability, genetic correlations and projected growth curves and breeding values for each animal were estimated. The parameter related to asymptotic weight was the most stable in reaction norms. However, parameters related to the initial conditions and slope of growth were influenced by nutritional gradient. Nutritional environment for quails should be similar to minimize interaction effects.