[Seasonal changes in the levels of various metabolites and proteins in cow milk and colostrum].

The studies on lactating black-and-white cows have shown that the content of albumins as well as of lactate, ammonia and glutamate in colostrum and milk of cows is higher in winter and spring but the level of beta- and gamma-globulins, citrate and urea is lower than the analogous indices in cows in summer. The concentration of alpha-globulins, oxaloacetate, malate and pyruvate in colostrum and milk did not change with the season.