ESTIMATES OF PHENOTYPIC AND GENETIC-PARAMETERS ON LIFETIME PERFORMANCE TRAITS IN MURRAH BUFFALOS

Analysis of performance records of 1 647 Murrah buffaloes revealed tha t the farms and years significantly influenced the lifetime traits. Th e least-square means for number of lactations completed, productive he rd life, lifetime milk yield and milk yield per day of productive herd life were 5.78+/-0.15 and 2 401+/-63 days and 9 993+/-338 and 4.00+/- 0.07 kg respectively. The corresponding heritability estimates of thes e traits were 0. 17+/-0.07, 0.17+/-0.07, 0.26+/-0.08 and 0.26+/-0.08. The phenotypic and genetic correlations of lifetime milk yield with nu mber of lactations completed and productive herd life were close to 1 and were higher than those of milk yield per day of productive herd li fe with longevity traits.