Estimation of genetic parameters for productive and reproductive traits in Iranian native buffaloes

In this study, calving records of 4221 Iranian native buffaloes from 621 herds which were collected by the Animal Breeding and Livestock Products Improvement Center of Iran from 2003 to 2010 were used to estimate heritability, genetic and phenotypic correlations between milk production, milk fat production, age at first calving and first calving interval using univariate and bivariate animal models. The highest and the lowest heritabilities were estimated for milk production (0.46±0.01) and first calving interval (0.01±0.29), respectively. Heritability estimates for age at first calving and milk fat production in the studied population were 0.21±0.21 and 0.27±0.17, respectively. Positive and high genetic correlation between milk yield and milk fat production (0.55) in this study indicated that milk fat increased along with increasing in milk production. Negative and medium genetic correlation between milk production and age at first calving (-0.25) indicated that genetic selection for milk production cause decrease in age at first calving. Positive and high genetic correlation between age at first calving and first calving interval (0.96) indicated that selection based on lower age at first calving cause reduced first calving interval.