Comparative evaluation of major milk quality parameters of Holstein and Simmental cows at different lactation stages under similar environmental conditions

摘要

The aim of this study was to evaluate the composition and quality parameters of Simmental and Holstein cows' milk with different lactation stages under the same environmental conditions. Multiparous Holstein and Simmental cows from different lactation stages (n = 210) were included in the present study. MDA, SCC, composition, and fatty acid analyzes were performed from the collected milk samples. To determine the effect of breed, lactation stage and their interactions, linear mixed models were applied to these parameters. Among the breeds, only milk fat and pH were determined statistically significant as composition parameters. While C15:0 and C17:1 n8 were observed to be statistically significant for the breed factor, C18:2 n6 trans were statistically significant only for the lactation stage factor. Moreover, the fatty acids of C4:0, C6:0, C8:0, C10:0, C11:0, C12:0, C13:0, C16:0, C18:1 n9, C20:0 and C22:6 n3 were determined to be statistically significant in terms of interactions. For the fatty acid indices, SCFA, MCFA, n3 and n6/n3 were statistically significant in terms of interactions while SFA, MUFA, UFA and AI were statistically significant in terms of breeds. On the other hand, new studies are needed to investigate the differences between these breeds at the molecular level for milk quality and fatty acid synthesis.