Use of California Mastitis Test, N-acetyl-beta-glucosaminidase, and antitrypsin to diagnose caprine subclinical mastitis.

Analysis of 448 milk samples (11 herds) from caprine udder halves showed that microorganisms were isolated from 21.8% of the samples. California Mastitis Test (CMT) and N-acetyl-beta-glucosaminidase (NAGase) were superior to antitrypsin in detecting subclinical infections. Coagulase-negative staphylococci and micrococci were the main species isolated from halves showing no clinical disease. Coagulase-positive staphylococcal infections were associated with a significant increase of all inflammatory parameters. Significantly increased CMT and NAGase occurred when streptococci, other staphylococci or micrococci were present. Infection within one half was reflected as an increase in the inflammatory parameters in the milk of the infected half as well as a slight increase in the inflammation parameters in the adjoining half.