The Effects of Total Mixed Ration and Separate Feeding on Lactational Performance of Dairy Cows

The aim of this study was to investigate the effects of different feeding systems on milk production and milk composition of dairy cows. Thirty-two dairy cows having similar lactation number, Days in Milk (DIM), live body weight and milk production was divided into four groups. First group received Total Mixed Ration (TMR) ad libitum, second group received roughage and concentrate limited and separately in two meals, third group fed with partial TMR which included half of the concentrate in roughage part of the diet and remained concentrate was offered in two meals, and the last group was fed with roughage and concentrate separately and roughage was offered limited in two meals and concentrate was offered limited in four meals. The feeding systems affected dry matter intake (P<0.05). Limited feeding groups were fed on roughage and concentrate separately, the roughage intake in these groups was decreased, concentrate ratio was increased in the diet as well especially in the group receiving concentrate in two meals (P<0.05). In TMR group, milk yield was significantly increased due to increase in their feed intake (P<0.05, 2 kg/day higher than others). Milk total solid, fat and urea nitrogen contents were affected by feeding systems. Restricted and separate feeding system groups had lower total solid, fat and urea nitrogen in milk (P<0.05). In conclusion, the results showed that restricted and separate feeding of concentrate and roughage may not be applicable in practice as it decreased feed intake, milk yield and milk fat test.