The objective of this study was to propose and discuss a method to compare the feed into product conversion between two experimental groups of beef cattle based on regression techniques. The mathematical and statistical procedures were developed using a databank of dry matter intake and average daily gain of 380 purebred or crossbred zebu animals on the BR-CORTE nutritional system database. Two groups were selected from the databank and were formed by Nellore (n = 156) or F1 European × Nellore (n = 139) animals. Two approaches were presented, based on linear and non-linear regression models fitting; the average daily gain and dry matter intake were used as independent and dependent variables, respectively. The food utilization by the animal was stratified into maintenance demand and true efficiency of product conversion. The difference between groups was evaluated by using dummy variables. The Akaike information criterion was suggested to decide which model is more adequate. The comparative evaluation of feed into product conversion between two experimental groups of beef cattle by using regression techniques allows, if suitable, the stratification of groups according to efficiency of diet utilization for maintenance and production.
Akaike information criterion; dummy variables; linear regression; non-linear regression
