Akademik Veri Yönetim Sistemi
Mediterranean Agricultural Sciences, cilt.31, sa.3, ss.310-315, 2018 (Hakemli Dergi)
The aim of this study was to estimate the genetic parameters and environmental factors for testday milk yield (TDMY), lactation milk yield (LMY), 305-day milk yield (305-DMY), milk fatpercentage (FP) and milk protein percentage (PP) of Jersey cows raised on KaraköyAgricultural State Farm in Samsun province of Turkey. The data were obtained from 279 milkyield records of 170 heads cows calved from 2011 to 2013 years. Parity, calving season andcalving year were considered as fixed effects. Heritability, additive genetic variance andphenotypic variance were estimated by multiple trait derivative free restricted maximumlikelihood (MTDFREML) with the animal model. Variance analysis results showed thatexcept for FP, the effects of parity and calving year on TDMY, LMY, 305-DMY and PP weresignificantly important (P<0.05). However, calving season did not affect TDMY, LMY, 305-DMY, FP and PP (P>0.05). Heritability estimates for TDMY, LMY, 305-DMY, FP and PPwere 0.38, 0.30, 0.28, 0.19, and 0.36, respectively. Repeatability for TDMY, LMY, 305-DMY, FP and PP were ranged from 0.35 to 0.45. The results indicate that these traits can beused as a selection criteria in genetic improvement of Jersey cattle this herd.