Relationship between parity and mineral status in dairy cows during the periparturient period

Data from 65 cows were collected to clarify the relationship between parity and mineral status in Holstein cows during the periparturient period. Milk fever occurred in a second‐ and a fourth‐lactation cow at parturition. Bodyweight of cows decreased immediately after parturition, and the decreased weights of cows from 1 to 6 days after parturition ranged from 11 to 27 kg. Milk yield of multiparous cows was higher than that of primiparous cows, but Ca and P concentrations in colostrum were not affected by the parity. Plasma glucose of primiparous cows was higher than that of multiparous cows, and plasma nonesterified fatty acids of fourth‐and‐more‐lactation cows at parturition was highest. Plasma Ca concentration of cows at parturition decreased with advancing parity, and plasma inorganic P concentration of third‐and‐more‐lactation cows was lowest at parturition. Plasma parathyroid hormone of fourth‐and‐more‐lactation cows at parturition was highest, but plasma hydroxyproline and alkaline phosphatase was lowest. These results suggest that the large transfer of Ca and P to colostrum is a factor in the development of milk fever in third‐and‐more‐lactation cows.