Abstract
To evaluate cellular immunity in Japanese Black (JB) calves, changes in peripheral leucocytes were com-pared in two groups of calves–JB calves (JB group;n=10) and Holstein calves (Hol group; n=10). In both groups flow cytometric analysis (FCM) was used within 3 days (0 week) and 3, 6, 9, and 12 weeks after birth.Forward (FSC) and side-scatter (SSC) dot-plots were examined and used to construct monocyte-lymphocytes gates of 3 sizes (small, medium, and large). In both groups, numbers of medium (M)-ML were low in 0 week but increased after birth. In the JB group, however, numbers of M-ML decreased at from 6 to 9 weeks and were significantly lower than those in the Hol group from 6 weeks after birth. Numbers of small (S)-ML in the JB group peaked at 3 weeks and were significantly higher than in the Hol group at 0, 3, 9, and 12 weeks. FCM analysis showed that numbers of CD3+ cells in the JB group were significantly higher than those in the Hol group at 3 weeks after birth. These results indicate that cellular immunity in JB calves differs from that in Hol calves because of changes depending on the role of the T cell.
