Heritabilities and genetic trends for reproductive traits in a population of Romosinuano cattle in Colombia

Objective. The aim of this study was to estimate heritabilities and genetic trends for reproductive traits in a beef cattle population Romosinuano. Material and methods. Age at first calving (AFC), first calving interval (FCI), and second calving interval (SCI) were evaluated from a database generated from 1951 to 2011 by Research Center Turipana. Unicaracter animal model was used, which included fixed of contemporary group (year-season), random direct genetic additives effects and residual. Estimates of variance components and genetic parameters were obtained through Restricted Maximum Likelihood procedure, using AIREMLF90 program. Genetic trends were calculated as a linear regression of weighted averages of breeding values over the years, using the REG procedure of Statistical Analysis System. Results. The indices of heritability for additive genetic effects were 0.04 ± 0.05 for AFC, 0.06 ± 0.06 for FCI, and 0.09 ± 0.06 for SCI. Conclusions. Low heritabilities indicating that should improve nutritional and management conditions in the herd, so that they can better express the traits evaluated. The estimated genetic trends were near zero, which shows that the objective of the CI Turipaná regarding this population has complied fully preserving the genetic variability of the breed Romosinuano.