Proteomics-based study for evaluation crossbreeding advantages of cattle-yak milk

Cattle-yaks are increasingly cultivated to boost yak dairy production while reports claim that will decrease the nutritional value of yak milk. However, studies on protein composition differences, especially functional proteins, between yak and cattle-yak milk are limited. This study explores these differences using data-independent acquisition (DIA) proteomics to compare whey proteins and milk fat globule membrane (MFGM) proteins in both types of milk. The results showed most up-regulated differentially expressed proteins (DEPs) in cattle-yak milk are more involved in promoting calcium absorption, immune regulation, and intestinal health which are essential nutrients for the growth and development of infants. Notably, the most important functional protein lactotransferrin and osteopontin content in cattle-yak milk are 8.03 and 3.44 times higher than that in yak milk respectively. This study sheds light on the potential crossbreeding advantages of cattle-yak milk and provides scientific evidence for cattle-yak breeding and the exploration of its milk.