Modeling of pig growth by S-function - least absolute deviation approach for parameter estimation

The aim of this study was to determine a mathematical model which can be used to describe the growth of the pig. The study was conducted on 60 pigs (30 barrows and 30 gilts) in the interval between the age of 49 and 215 days. All animals were weighed at 49th day after birth. For the purpose of growth measurements pigs were weighted every 7th day during the experiment. Every 21th day four pigs were selected for the slaughter according to average live weight. By applying the generalised logistic function, the growth of live weight and tissues were described. Thereby optimal parameters in the model were estimated on the basis of measurement data by means of the robust least absolute deviations principle. The prediction of optimum slaughter age/weight, on the basis of such model represent a contribution of this paper to the practice.