Mutual relationship between milk components and lysosome enzymatic activity in abnormal milk.

Abstract

Quarter milk samples (67) of lactating cows were investigated to verify the relationship among lysosome activity, cell count and milk components. Of lysome enzymes, N-acetyl-.beta.-D-glucosamindase (NAGase), .beta.-glucuronidase [.beta.-glu] and acid phosphatase [AP] exhibited a high correlation with cell count. When the cell count was expressed in log, NAGase showed a correlation coefficient ranging from 0.679-0.769 and .beta.-glu from 0.592-0.7920. AP showed a decrease in the correlation coefficient from 0.680 to 0.432. NAGase showed a high correlation with .beta.-glu, AP and arylsulfatase (0.672-0.675). Aldolase exhibited a high correlation with NAGase (0.687) and AP (0.682), but not with .beta.-glu. Cl- exhibited a remarkably high correlation with NAGase (0.875) and arylsulfatase (0.767) and a low correlation with .beta.-glu. When examined with enzymatic activities, lactose correlated to NAGase with r = -0.810, to AP with r = -0.676, to arylsulfatase with r = -0.687 and to aldolase with r= -0.612. When examined for correlation with each enzymatic activity, milk protein showed a high correlation with .beta.-glu and .alpha.-mannnosidase. Milk fat exhibited a correlation with .beta.-glu, .alpha.-mannosidase and arylsulfatase (r = 0.453-0.567). Thus, of the lysosome enzymes, NAGase can be used as an indicator of inflammation in the udder; .beta.-glu may be useful for diagnosis of mastitis.