The Study Of Milk Composition And Fatty Acid Constitution Of Dairy Cows In The Inner Mongolia

The objective of present study was to measure and compare the difference of milk composition and fatty acid content and constitutions among total 720 Holstein, Simmentals and Sanhe cows from different places, Hohhot, Bayan Nur, Tongliao and Hulun Buir, of which were in different breeds, parities, lactation periods and seasons. The results indicated that milk protein and fat contents of Holstein cow from Tongliao and Hulun Buir were significantly (P<0.05) higher than cows from Hohhot and Bayan Nur, but DM, lactose and casein content had no significantly (P>0.05) difference. In milk, USFA contents of Holstein from Tongliao and Hulun Buir were significantly higher than that of Holstein from Hohhot and Bayan Nur (P<0.05), and MCFA contents of Holstein from Tongliao and Hulun Buir were significantly lower than that of Holstein from Hohhot and Bayan Nur (P<0.05).Fat and total dry matter content in the milk of Simmentals and Sanhe were significantly higher than that of Holstein (P<0.05), and there were no significant (P>0.05) difference of fat and dry matter content between Simmentals and Sanhe. The significant difference of protein, lactose and fatty acid content among three breeds was not seen (P>0.05). Comparing Simmental and Sanhe with Holstein cows, the outstanding feature of fatty acid was that in milk, SFA content of Simmental and Sanhe was significantly lower than that of the Holstein (P<0.05), but USFA content was significantly higher than that of Holstein (P<0.05).Milk fat content from the first and third Parities Holstein was significantly higher than that of the fifth Parity cows (P<0.05), and there were no significant difference of other milk nutritional ingredients among the three breeds (P>0.05).The milk fat contents of Holstein, Simmentals and Sanhe in early lactation and later lactation periods were significantly higher than that of middle lactation periods (P<0.05), and there were no significant (P>0.05) variation of milk composition during three lactations periods.Milk content in fading period of pastoral area was significantly higher than that of other seasons (P<0.05) and there were no significant variation of milk composition during all year period (P>0.05). In pastoral area, USFA content in flourishing period and early fading period was significantly higher than that of fading budding period (P<0.05), and fatty acid content and constitutions was not significantly (P>0.05) affected by the season variation.