Study of reproductive trends in Canchim animals, breeding in pasture, in Paraná State, Brazil

Abstract

Beef production efficiency depends heavely on reproductive performance. Information on age at first calving indicates sexual precocity. Good management of young animal and elimination of factors that negatively interfere with growth and development of heifers contribute to shorten age at first calving. This trait, together with calving interval and conception rate of heifers after their first calving were studied from records of 3.091 Canchim females, born from 1974 through 1998, at Estação Experimental Fazenda Modelo/IAPAR, Ponta Grossa-PR. Data were analyzed using SAS program. Average calving interval, computed using least squares methods, was 16.79 ± 0.43 months, with coefficient of variation equal to 32.07. The R square from the statistical model was 19.84%. For calving interval, only year of birth, month of birth and month of previous calving were significant. When interval between first and second calving was studied, month of previous calving was not significant. Considering that data came from controlled animals, the average calving interval was too long in contrast with the ideal (12 months). Improving management practices should result in shorter calving interval in this herd.