DETERMINATION OF SELECTION INDEX FOR BIRTH WEIGHT AND WEANING WEIGHT IN THE BRAHMAN BREED CATTLE

Objective. To Estimate a selection index for birth weight and weaning weight in Brahman cattle on the north coast of Colombia. Material and methods. To calculate this index we estimated the components of variance between and inside of the reproducer, and the genetic and phenotypic covariances between the characteristics in the study, using the procedure MIXED of SAS. Results. The estimated index was I=X1-0.4286X2, obtaining maximum correlation between aggregate genotype and phenotype, becoming a tool of genetic improvement to make the selection process more technical and efficient and to achieve greater genetic progress per unit time. Conclusions. We recommend the use of animals of higher index, as there is correlation between the index and the aggregate genotype.