Abstract:Variation law of the regular nutritional ingredients in yak colostrum with different parities and lactation days was studied. The results showed that in the first parity the protein content was lower than the other parities with no significant difference -p>005-; the dry matter's content was lower than the other parities with slight difference except the first and fourth day; the lactose content was higher than the other parities with no significant difference -p>005-. The fat content in the first and fifth parity was lower with no significant difference -p>005-. The ash content in all the parities was almost at the same level -p>005-. The contents of protein, fat, dry matter and ash were the highest in the first day of lactation, and tended to decrease with the lactation days. Instead, the lactose content was the lowest in the first day, and increased gradually in the following days. Understanding the variation law of the regular nutritional ingredients in yak colostrum would help explore more the milking performance, and provide theoretical basis for developing yak colostrum products.