Relationship between lysosomal blood activity and milk contents of urea and protein in different phases of milk production in dairy cows

Relationshiop of lysosomal enzyme activities in blood and supply of energy and protein in dairy cattle were investigated. Closed correlation coefficients were calculated for lysosomal enzyme activity and content of protein and urea in milk. Especially a high or a low content of protein in the food ration affects the lysosomal enzyme activities considerably. A different lysosomal response to equal food supply was gained after deviding the cow stock into different groups regarding performance at a different lactation status. Growth, breed, age, capacity of food intake and milk performance might be influencing factors.