Eficiência reprodutiva e produção de leite em zebuínos da raça Sindi

Abstract

Livestock productive process is based primarily on reproductive efficiency of the cattle breeding. An appropriate reproductive efficiency of cattle is essential to maximize the milk and meat production. Reproductive efficiency is one of the parameters to evaluate the productivity of cattle on climatic, nutritional, genetic and management conditions. Zebu breeds are applied to the climate of the tropics. The Sindhi breed, with a double ability, is one of the many zebu breeds raised in Brazil and has been studied for the milk genetic improvement. In this sense, the aim of this study was to identify the productive and reproductive averages of Sindhi breed females and evaluate if there is influence of reproductive parameters on milk production in this breed when raised in different regions of Brazil. To this end, data provided by ABCZ on the reproductive and productive performance of 638 dairy cows Sindhi breed, raised the North, Northeast, Midwest and Southeast regions of Brazil, were collected. For statistical analysis, the computer program SAS (Statistical Analysis System) (2004) were used, which initially analysis of variance (proc GLM) was performed, followed by analysis of correlation (proc CORR) among reproductive traits and between these and the milk production. Averages for age at first calving (IPP), calving age (IP), calving interval (IDP), service period (PS), reproductive efficiency (ER), milk yield (PL), lactation period (DL) and total milk production (PTL) were respectively 1549.83 ± 560.47 days; 1843.53 ± 739.99 days; 533.28 ± 206.66 days; 248.28 ± 206.66 days; 75.46 ± 19.95%; 7.08 ± 2.78 kg of milk.day-1; 263.22 ± 63.51 days and 1875.28 ± 893.36 kg of milk.lactation-1. The parameters IPP, parity order (OP), IP, IDP, ER and DL were separated into categories and there was no significant difference of milk production among different categories. Parity order showed correlation with the lactation period, showing that the lower the parity order, the lower will be the lactation period. Therefore, it can be concluded that Sindhi breed showed high values for age at first calving and median values for milk production, calving interval and reproductive efficiency when compared to the reproductive parameters Brazilian averages for zebu.