Abstract
A response of phagocytes in an udder secretion was investigated in normal and mastitis cows by an administration of chitosan (50mg) through the teat canal, respectively. The number of phagocytes and the intensity of chemiluminescence in the udder secretion increased just from the next day after the chitosan administration in both the normal and the mastitis cows. These phenomena were maintained over one week in the mastitis cows, but returned to the normal level within one week in the normal cows. A lebel of lactoferrin in the normal udder secretion increased significantly during 7 days after chitosan administration.
