Growth curve in Mambrina goats raised in caatinga

Abstract

The objective of this work was to evaluate the application of non-linear models to describe the growth of Mambrina goats. Data from 18 monthly weights of 45 animals, at 540 days of age, were used. The non-linear models tested were: Brody, Von Bertalanffy, Richards, Logistic and Gompertz. The Logistic, Bertalanffy and Gompertz models presented the best adjustment, being the Logistic slightly superior to the others. Sex did not influence the curve parameters. Mambrina goats, mainly female individuals, present low weights at maturity, indicating they are well-adapted to the adverse conditions of the region. The individuals should be slaughtered early, before reaching the age of 240 days, since their growth is very slow from this age on. The correlation estimated between the parameters A and k was moderate and negative (-0,68), indicating that the more precocious the animals, less likely they will reach high weights when adults.