Effects of Glutamic Acid Residue on Growth and Blood Biochemical Indexes of Qinchuan Beef Cattle

The aim of the study was to research the effects of glutamic acid residue on growth and blood biochemical indexes of Qinchuan beef cattle. 12 bulls of 18-month-age,12 cows of 18-month-age and 12 bullocks of 8-month-age were selected and randomly allocated to 4 groups with 9 cattle per group (including 3 bulls,3 cows and 3 bullocks) in a single factor randomized block design.The control group and groupⅠ,Ⅱand Ⅲ were used 0,1.5%,3.0%,4.5% glutamic acid residue to replace part of soybean meal of diets. Feeding trial lasted for 100 d.Intake and body weight were measured at each stage during trial periord.At the end of the experiment, blood samples were collected to detect blood biochemical indexes.The results showed as follows:The average daily gain(ADG) of cattle in group Ⅰ,Ⅱ and Ⅲ were significantly higher than that of control group (P<0.05),and the value of group Ⅱ was significantly higher than that of group Ⅰ and Ⅲ (P<0.05). The dry matter intake (DMI) of cattle in group Ⅱand Ⅲ were significantly higher than that of control group (P<0.05). The feed/gain ratio (F/G) in group Ⅱwas significantly lower than that of control group (P<0.05).As for the blood biochemical indexes, the contents of alkaline phosphatase of control group, groupⅠand Ⅱwere significantly higher than that of group Ⅲ (P<0.05), and there were no significant differences for other biochemical indexes (P>0.05). The correlation between the average daily gain and the blood content of alkaline phosphatase was extremely significant (P<0.01). In conclusion,it could improve feed intake, daily gain (increased by 22.62%) and decrease the F/G (decreased by 10.85%) by using 3.0% glutamic acid residue replacing part of soybean meal in diets for Qinchuan beef cattle. Adding appropriate glutamic acid residue (1.5% to 3.0%)in diet could increase the level of blood alkaline phosphatase,which should be an important index to reflect the growth of Qinchuan beef cattle.