Milk composition at different stages of lactation in first-calving cows of Military Farm at Savar, Bangladesh

Objectives: The present research work was taken up to examine the changing pattern of colos¬trum to normal milk and also to monitor the effect of phages of lactations on compositional changes of milk produced by Holstein-Friesian Crossbred cows of Military Farm Savar. Materials and Methods: A total of 05 milking cows from the first calving were selected. Colostrum samples were gathered on calving and the 5th day after calving. The concentration of major ingre¬dients [fat, protein, lactose, total solids (TS), solid-not-fat (SNF), and ash] changed significantly after birth, the day on 5, similar to normal milk. The average values of specific gravity, fat, protein, lactose, TS, SNF, and ash content of colostrum were observed on day 1 and day 5. Results: The specific gravity was 1.045 and 1.031, respectively. The fat, protein, and lactose con¬tents of colostrum on day 01 and day 05 after calving showed a significant difference. The compo¬sition of whole milk showed that the specific gravity was 1.029. According to the different stages of lactation, it was found that the protein, lactose, fat, TS, SNF, and ash content were lower in the first 2 months of lactation. After 3 months of lactation, it started to increase, and there was a significant change at the end of the sampling period. Conclusion: The composition of colostrum and milk of Holstein-Friesian crossbred cows was within the normal range, and the changing pattern was similar to the other dairy breeds.