Effect of Restriction of Dry Matter and Nutrient Intakes on Productivity of Holstein Lactating Cows Offered High Levels of Concentrate

TLDR: It was concluded that to allow ad libitum feeding of diet containing high levels of concentrate to the lactating cows might decrease the efficiency of feed nutrients and hence result in no positive effect on productivity of milk.

Abstract: Effects of dry matter intake restriction to the level of recommend by NRC (2001) on intake balance of dry matter and nutrients in Holstein lactating cow were evaluated. 24 lactating cows were divided into two groups and individually fed one of the TMR offered as ad libitum (control) and restricted amount (treatment) as recommended by NRC (2001). Milk yield including 4% FCM and FPCM were showed higher tendency in treatment group then those of control group. Also, intakes of dry matter, net energy and metabolizable protein were tended to be higher in treatment group then control group. Actual dry matter and net energy intakes in control group were higher (p<0.001) then those of recommended amount by NRC (2001), whereas no significant differences in treatment group. The estimated NEL allowable milk yield were lower (p<0.001) in both control and treatment group than those of recommended by NRC (2001). It was concluded that to allow ad libitum feeding of diet containing high levels of concentrate to the lactating cows might decrease the efficiency of feed nutrients and hence result in no positive effect on productivity of milk. (Key words : Intake control, Dry matter intake, Net energy intake, Metabolizable protein intake, Milk production, Holstein lactating cow)