Direct and Maternal Genetic Effects and Temporal Trends of Economic Traits in Surti Buffaloes

This study evaluated the genetic parameters and decadal trends of economic traits in Surti buffaloes using 868 lactation records maintained between 1993 and 2023 at the Livestock Research Station in Udaipur, Rajasthan, India. The analyzed traits included total milk yield, 305-day milk yield, peak yield, lactation length, calving interval, dry period, and average daily milk yield per lactation length and calving interval. Variance components were estimated using restricted maximum likelihood procedures under three repeatability animal models. Heritability estimates ranged from 0.005 (CI) to 0.093 (ADMY_LL), and repeatability estimates ranged from 0.195 to 0.331. Model 1, accounting for additive genetic and permanent environmental effects, was most suitable for practical use. Strong genetic and phenotypic correlations were observed among the milk yield traits, whereas the reproductive traits exhibited more variable associations. Genetic trends revealed substantial declines per decade in TMY (−97.71%), TMY_305 (−123.82%), PY (−231.32%), ADMY_LL (−231.90%), and DP (−104.49%). In contrast, positive genetic gains were observed for CI (166.76%), ADMY_CI (111.34%), and LL, indicating improvements in reproductive efficiency and yield persistence. These findings highlight the need for a balanced selection strategy targeting both production and reproductive traits, supported by refined management practices in Surti herd.