Pertaining to the scenario at hand milk samples from Holstein x Hariana crossbred cows were investigated for alternation in enzyme activity as influenced by sub clinical mastitis (SCM) and their percent sensitivity,specificity,accuracy,positive and negative predictive values, positive and negative likelihood ratios and correlation with (somatic cell count) SCC were calculated. It was found that SCM influence significantly the activity of ALP at pO.OIand LDH at pO.O5in milk. Aspartate amino transferase activity was not influenced by SCM in milk. Moreover, both were found to be correlated with somaticcellcount, significantly.Fromthe likelihoodratios itwas clearthat both alkalinephosphatase (ALP) and LDH can be used for diagnosis of SCM, but, ALP is the safe indicator of SCM in the present study.

The activity of lactate dehydrogenase in plasma and various tissues (skeletal muscle, cardiac muscle, liver, lung, kidney and spleen) of Korean native cattle in a Choju abattoir, the Breeding Stock Farm and Animal Farm of Chonbuk University was determined by using ultra violet method. Using polyacrylamide gel electrophoresis, the lactate dehydrogenase isoenzyme distribution of plasma and various tissues in Korean native cattle was studies. The plasma lactate dehydrogenase activity of Korean native cattle was 554.80 +- 92.70 IU/L and the lactate dehydrogenase activity of male plasma was 543.96 +- 97.89 IU/L, which was lower than that of female plasma, 579.19 +- 78.09 IU/L. The plasma lactate dehydrogenase activity of calf was 557.31 +- 110.27 IU/L and was not significantly different from that of adult Korean native cattle. But the range of calf lactate dehydrogenase activity was larger than that of adult Korean native cattle. In tissues, the lactate dehydrogenase activity was decreased in order of lung, kidney, spleen, liver, heart and skeletal muscle. The lung had the greatest activity and the skeletal muscle had the least. Lactate dehydrogenase isoenzymes in plasma and tissues were found to have a characteristic distribution and quantitative isoenzyme patterns. In plasma, the LDH1 usually had the greatest activity and other isoenzymes showed a decreasing tendency in order of LDH2, LDH3, LDH4 and LDH5. The distribution of lactate dehydrogenase isoenzymes had a wide variation in tissues. But the distribution of LDH isoenzymes in plasma was similar to that in kindey, and also cardiac muscle and spleen had similar pattern in LDH isoenzymes distribution