A high incidence of mastitis occurs in dairy cows during the postpartum period, but its cause is unclear. Because leukocytes in colostrum have an important role in preventing the onset of mastitis, we investigated the leukocyte populations which express CD4, CD8, CD14, CD21, or WC1 in colostrum as well as in blood obtained from 14 Holstein cows. Eight cows developed mastitis within a week after calving, whereas the other 6 remained healthy. The percentage of CD14+ cells in the colostrum of mastitic cows was significantly lower than that of healthy cows. No significant differences were found in other marker-positive cells in either colostrum or blood. The CD14+ cells in colostrum play an important defensive role against invading microorganisms in the mammary glands. Our results suggested that the lower percentage of CD14+ cells in colostrum might predict the incidence of mastitis in the postpartum period.
(Dairy Hygiene Research Division)
References:
Kiku Y. et al (2010) Vet. Res. Commun. 34(2):197-203
