Research of the changes of vitamins of yak colostrum and transient milk

Yak colostrum and transient milk within the first 7d after parturition as the research object, the changes of vitamin A, vitamin E and B vitamins during the different lactation periods were analyzed by HPLC. The results showed that the highest concentration point of VA, VE, VB1, VB2 and VB3in yaks colostrums was on the 1st day, the numbers respectively reached 367.76, 780.11, 93.41, 367.76, 98.93μg/100 g, respectively. Besides, the numbers had a sharp decline with the process of lactation (p<0.05) and gradually became moderation 3 days later. The lowest concentration (201.49μg/100g) of VB5 was observed in yak colostrum on the 1st day and increased dramatically in the first 3 days (p<0.05) , followed by a slight increase. The concentrations of VB6 and VB11were not affected by the studied lactation. In addition, the concentrations of VA, VEand VB1 in primiparous yak colostrums and transient milk were higher than the multiparous, and other vitamins were not affected by the parity. The results provided theoretical basis for reasonable exploitation and utilization of yak milk resources.