Effects of feeding frequency and adding oil to diet on performance, sorting behavior and rumen fermentation of Holstein dairy cows

The objective of this experiment was to investigate the effect of feeding frequency and oil supplementation to the diet on sorting behavior and rumen fermentation of lactating dairy cows. Twenty four lactating Holstein cows, including 12 primiparous with average body weight of 626 ± 58 Kg and days in mild of 195 ± 44 day, and 12 multiparous having average body weight of 617 ± 25 Kg and days in milk of 207 ± 39 day, were used in a 2×2 factorial experiment under a randomized complete block design. The factors were oil supplement at two levels of 0 and 25 percent, and feeding frequency of 1 or 3 times per day. Treatments had no significant effect on dry matter intake and fat and energy corrected milk, but uncorrected milk production was lower for three times feeding without oil supplement (P 0.05). The primiparous cows showed more sorting behaviors than multiparous cows (P