Factors Affecting the Total Milk Yield in Holstein Cattle under Intensive Production Conditions in Syria

This study was conducted at Fedio Dairy station that belongs to the General Establishment for dairy cattle production at Lattakia. A total of 3861 milk yield records for 1508 Holstein cows were used in this study during the period from year 1989 to 2010 to find factors affecting Total Milk Yield (TMY). Data were analyzed following the General Linear Model (GLM) in which analyses of variance were used to determine the effect of calving year, calving season, parity and their two –way interactions on the TMY. The TMY (5297.3±28.43 kg) was significantly affected (P 0.001) by calving year, parity and interactions between studied factors (which they are ……etc), and (P 0.01) by interaction (calving year × parity). There was no significant effect for season, interactions (calving year × calving season) and (calving season × parity) on TMY. Results suggested that better management practices and improving the feeding status might help increasE total milk yield and making the status more economic and efficient at dairy cattle at station.