Energy requirements for maintenance of growing Saanen goats considering degree of maturity

Abstract

The aim of this study was to perform a meta-analysis for predicting net energy requirements for maintenance in intact male, castrated male and female dairy goats, considering the degree of maturity. A database of 206 goat kids weighing from 4.3 to 51 kg body weight (BW), from seven comparative slaughter studies was used. The experimental design of each study provided different levels of metabolizable energy intake (MEI) and empty BW (EBW). The inclusion of the degree of maturity in the model was evaluated applying the relative EBW. Non-linear regression equations were developed to predict heat production (HP; kcal/kg relative EBW; dependent variable) from MEI (kcal/kg relative EBW; independent variable) using NLMIXED. The net energy requirement for maintenance (NEM) was calculated as the value of HP at MEI equal to zero. The requirements were similar between sexes at five degree of maturity. The lack of differences in energy requirements for maintenance of males and females considering the mature weight is likely a response to similar body fat and protein amounts in goats at the same degree of maturity.