Efeito de linhagem e sexo nas características geométricas e biomecânicas de tíbias de frangos de corte

Abstract

The intensive rearing of broilers, combined with nutrition and genetic improvement focused on weight gain has resulted in increasing rates of leg problems. Among the variables that may contribute to the occurrence of these problems are sex and lineage. In this context, the study evaluated the geometric and mechanical properties of the tibiae of broilers, male and female, from three commercial lines in the final growth stage, between 21 and 42 days. The geometric characteristics reflect the adaptive response of bone, with a direct relationship between their dimensions and the live weight of birds. As for the mechanical properties obtained from bending tests, it is observed that the evaluation of bone strength can lead to different conclusions depending on the mechanical parameter considered. Heavier birds, with larger bones, support more load in bending. However, when intrinsic strength parameters of the material are considered, such as bending strength, it is observed that the heavier line does not show significantly different values from the others. The same occurred among males (heavier) and females. Thus, heavier birds may be more susceptible to structural leg problems, as their tibias are as strong as those from lighter birds.