Influence of calving difficulty on dry matter intake immediately after calving of dairy cows.

Abstract

We investigated the influence of calving difficulty on dry matter intake (DMI) in Holstein cows immediately after calving using 15 pregnant heifers and 15 multiparous cows. DMI was measured for 6days after calving. Calving difficulty was evaluated with a calving score, and urinary cortisol was measured. The calving score was higher in the first lactation heifers than in the multiparous cows. The average DMI 6days after calving was lower in the first lactation heifers than in the multiparous cows. The urinary cortisol concentration at 4days after calving was higher in the first lactation heifers than in the multiparous cows and was positively associated with the calving score. The DMI was negatively associated with the calving score and the urinary cortisol concentration at 4days after calving and was positively associated with the average milk yield 6days after calving and the serum calcium concentration at 3days after calving. We conclude that DMI immediately after calving is influenced not only by nutrient requirements of cows but also stress derived from calving, and the low DMI in the first lactation heifers is due to the lower energy requirement and high susceptibility to the stress compared with multiparous cows.