Growth curve prediction of holstein-fresian bulls using different non-linear model functions

Abstract

This study aimed to determine the best model to explain the variations in the live weight of Holstein bulls using non-linear function models such as Brody’s, Gompertz’s and Richards Logistic. For this purpose, live weight records of 51 Holstein Fresian male calves reared in Dicle University Cattle Research Farm were used. In order to estimate the best model, the coefficient of determination (R2) and the residual mean squares (RMS) statistics were utilized. The coefficient of determination (R2) for Gompertz’s, Richards Logistic and von Bertalanffy models were found to be 0.999, 0.999, 0.998 and 0.999 respectively. Residual mean squared were found to be 21.41, 16.82, 50.94 and 22.21, respectively. As a result, the Richards model used in the study was found to be the best fitted model based on RMS and R2 criteria. It is the more suitable model due to its accurate ability to predict mature weight, which is an important selection goal.