Akademik Veri Yönetim Sistemi
JOURNAL OF ANIMAL AND VETERINARY ADVANCES, cilt.7, sa.10, ss.1218-1222, 2008 (SCI-Expanded)
The study was carried out to determine the effect of environmental factors on milkability traits and to estimate genetic parameters and relationships among milk yields, milk flow rate (MFR) and milking time (MT) of Brown Swiss cows reared in Eastern Region of Turkey. The data used in this study consisted of 2051 observations of milking time and milking flow rate on 315 lactations of 163 cows. The averages for MFR, MT and total test day milk yield (TTDMY) were 0.972 kg min(-1), 5.46 min and 11.35 kg, respectively. Stage of lactation and parity had significant (p<0.01) effect on the MFR, MT and TTDMY. Multiparous cows had higher MT and TTDMY (p<0.01) than primiparous cows. Calving season only significantly (p<0.01) affected on TTDMY. The heritability estimates for MFR, MT and TTDMY were 0.37, 0.37 and 0.21, respectively. The positive genetic correlations of MFR with actual milk yield, 305 days milk yield, TTDMY were 0.423, 0.585 and 0.735, respectively, while negative genetic correlations between MT and milk yield traits were calculated. The higher heritability values for MFR and MT suggested that selection of a good milkability seems to be promising and genetic improvement in MFR and MT might be achieved through selection for milk production.