COMPOSITION, YIELD AND FREEZING POINT OF COLOSTRUM AND MILK FROM HOLSTEIN × SAHIWAL COWS IN A COMMERCIAL DAIRY FARM IN BAY, LAGUNA, PHILIPPINES

Abstract

This study compared the milk components and freezing point of 184 colostrum and milk samples obtained on the 30th, 60th, and 90th day in lactation of 46 Holstein × Sahiwal cows on a commercial dairy farm in Bay, Laguna. Colostrum contained 4 times higher percent protein and 1.1–1.4 times higher percent fat but 1.66–1.95 times lower percent lactose than milk. The freezing point was not significantly different between colostrum and milk (P>0.05). The proportion of milk components and freezing point were not significantly different in milk collected on different days of lactation. Cows at higher parity had higher protein and lower percent lactose in colostrum, and higher percent fat in milk. In colostrum, percent fat was positively correlated with percent protein (r = 0.37) and SNF (r = 0.35). The proportion of the components of colostrum, however, was not significantly correlated to colostrum yield and freezing point (P>0.05). The protein, fat, and lactose yields were positively correlated with colostrum yield but not correlated with freezing point (P>0.05). In milk, percent protein was positively correlated with percent lactose (r = 0.53), SNF (r = 0.70), and total solids (r = 0.60), negatively correlated with freezing point (r = -0.72), but not correlated with percent fat (P>0.05). Milk yield was not significantly correlated to protein, fat, and lactose percent. The protein and lactose yields were highly correlated with milk yield and freezing point. The fat yield was moderately correlated with milk yield but not correlated with the freezing point. Milk freezing point was positively correlated with percent moisture and fat but negatively correlated with percent protein, lactose, SNF, and total solids.