The reproductive performance of Mantiqueira cows were analyzed using data of records of age of first calving (IPP), calving interval (IDP) and days open (PSERV). These data were the first five lactations of 1406 cows of Mantiqueira ecotype consisting of daughters of 113 sires, with calving from 1952 to 1997, from the Paraiba Valley Regional Center of Research in São Paulo State (APTA/SAA-SP) breeding program. Models to obtain least square means included fixed effects for year and season of birth (for IPP) or calving (for IDP and PSERV) and age, in addition to the random effect of sire and error. The models to obtain genetic parameters by REML methodology included fixed effects for year-season and age, in addition to the random effects of animal and error. The least square means ± standard error were 45.60 ± 8.14 months to the IPP, 460.56 ± 122.05 days to the IDP and 181.44 ± 110.31 days to the PSERV. Estimated values of heritabilities were: 0.13 (IPP), 0.01 (IDP), and 0.01 (PSERV).
Age of first calving; calving interval; days open; dairy cattle; Mantiqueira ecotype
