FIXED EFFECTS OF PRODUCTIVE PERFORMANCE IN DOUBLE PURPOSE SYSTEM

Abstract

Data of reproduction records of Brown Swiss (S) x Zebu (C) herd were evaluated, to determine the effect of some fixed factors on the calving interval (IEP, n=112), in a semi-intensive double purpose system. The study was carried out in the productive milk unit of El Ejido experimental facility, from 1996 to the 2006. The studied fixed factors were racial group (GR), intensification level (NI), parity number (NP), calving season (EP). The racial groups studied were ½ S X C (n=75) y ¾ S X C, (n=37). The overall mean was 438,84 ± 9,56 days. No significant differences were found in all factors except for NI. The NI 2 had the better behavior, showing a mean and standard error of 406,15 ± 15,17 days, representing 17% of diminution of unproductive days of the herd. We conclude that the influence of the applied technologies over a similar productive system may improve the productivity against the payments due to the generated oriducts in those herds.