REVIEW ON: HOW DOES PRE-CALVING NUTRITION INTERACT WITH POST-CALVING NUTRITION TO AFFECT MILK PRODUCTION AND CHANGES IN BODY CONDITION OF COWS?

 ABSTRACTMost of nutritional researches regarding transition cows has involved the feeding of total mixed rations or pasture silage and concentrate to cows before and after calving. The nutrition of dairy cows is believed to affect productivity early in lactation. Pre-calving nutrition has impact on body condition score (BCS) at calving. It has been suggested that increased level of feeding prior to calving is associated with increased BCS at calving and increased milk yield after calving. The effect of pre-calving feeding may be less evident in cows fed well post-calving. Over conditioned cows, unlike thin cows, produce milk with the expense of their stored fat and as a result they are in negative energy balance and they have low dry matter intake (DMI) during early lactation. It is better to achieve high energy concentration by the use of high-fiber concentrates with a fat supplement, and optimum performance in cows that are fat at calving may be achieved with higher level of undegradable dietary protein, whereas cows that are thin at calving perform best with higher levels of energy diet. This review explores pre- and post-calving nutrition and milking frequency and their effect on production parameters. In addition, I review the interaction between BCS at calving and nutrient intake during early lactation.     Key words: BCS; DMI; Milk Yield; NEB; Pre-calving; Post calvin