Study On Application Effect Of Three Kinds Of Attractants On Beef Cattle

Object:With the rapid development of animal husbandry in China,the application of green,non-residual,non-polluting attractants has become increasingly popular.In this thesis,we studied the effects of three attractants based on green pigment,fat-aromatic mixtures and cyclamate on feed intake,growth performance,digestion and metabolism,and serum biochemical indexes of Angus calves.Through the addition of three kinds of attractants,not only can significantly increase the feed intake of beef cattle,but also can make full use of Xinjiang agricultural and sideline products resources to provide scientific basis for rational use of roughage on ruminants and regulation of food intake.Methods:This thesis includes three trial contents.The research methods are as follows:Test 1:Effect of three kinds of attractants on intake and growth performance of Angus calves.24 healthy 6-month-old Angus calves with body weight similar to each other were randomly divided into 4 treatment groups,namely control group,green agent group,flavor agent group,sweetener group.The control group was fed with total mixed rations(TMR);The green agent group was TMR+chlorophyll 0.24%;the flavor group was TMR+XTRACT~?7065 1.2 g/d;the sweetener group was TMR+sodium cyclamate 0.4%.The preparation period of 10 d,the trial period of 30 d.Recording feed intake of calves every day and calculated ADMI;in fasting was weighed,the beginning and end of the record weight and calculate the ADG and feed-to-weight;at the same time,the determination of beef cattle body height,back height index and so on.Test 2:Effect of three kinds of attractants on the digestive and metabolic function of Angus calves.On the basis of test one,samples of treated grains and urine samples were collected during the test period and prepared for testing.The apparent digestibility of major nutrients and indicators of nitrogen metabolism were measured,among which the apparent digestibility of nutrients was detected by AIA.Test 3:Effect of feeding three kinds of attractants in diets on blood indexes of Angus calves.On the basis of experiment one,each test bovine serum was collected during the test period,and serum biochemical indexes and some serum hormone indexes were measured.Results:Test 1:(1)From 0 to 15 days,the ADMI in the green agent group and the sweetener group was respectively higher than that in the control group(P<0.05);15 to 30 days and 0 to 30 days,compared with the control group,the ADMI in the three experimental groups was significant higher than the control group(P<0.05).Compared with the control group,there was no significant difference in the body weight of the yak in each experimental group,on the 15th day and on the30th day(P>0.05).From 0 to 15 days of the trial,compared to the control group,the ADG of both the green agent group and the sweetener group was increased by 40.38%(P<0.05);from 15 to 30days and 0 to 30 days for the green agent group and the sweetener group,the ADG were also respectively higher than that of the control group(P<0.05);there was no significant difference in the feed-to-weight ratio between the experimental groups and the control groups(P>0.05).(2)Compared with the control group,the body measurements of the three test groups were not effectively different at the initial stage of the trial.On the 15th day of the experiment,the body height,body length and chest circumference of the three experimental groups showed a trend higher than that of the control group(P>0.05);compared with the control group,the recommended height,body straight length,tube circumference,body length index,body trunk index,and bust index of the experimental groups were not significantly different(P>0.05).On the30th day of the test,the height,body length,height,body length,chest circumference,tube circumference,body length index,body index,and bust index of the test groups were not respectively different from those of the control group(P>0.05).Test 2:(1)There was no significant difference in the apparent digestibility of DM,EE,and CP between the three experimental groups compared with the control group(P>0.05).Compared with the control group,the appearances of Ca,P,ADF,and NDF in the green agent group were significantly increased by 14.05%,8.99%,21.75%,and 9.95%(P<0.05).(2)Compared with the control group,the content of nitrogen in the green agent group and the sweetener group was markedly increased by 26.00%and 32.46%(P<0.05);the fecal nitrogen content in the green agent group and the sweetener group was significantly higher than that in the control group(P<0.05),but the fragrance group was respectively lower than the control group(P<0.05);the urine nitrogen content of the green agent group and the sweetener group was significantly higher than the control group by 15.59%and 23.04%(P<0.05);compared with the control group,the digestible nitrogen content of the three experimental groups was markedly increased by 18.60%,14.43%and 42.08%(P<0.05);the three experimental groups have significantly lower deposition nitrogen content than the control group(P<0.05);The nitrogen digestibility of the fragrance and sweetener groups was significantly higher than that of the control group(P<0.05);compared with the control group,the nitrogen utilization of the flavor and sweetener groups increased significantly 23.97%and 22.85%(P>0.05).Test 3:(1)On the 15th day and the 30th day of the experiment,compared with the control group,the changes of GLU,TP,ALB,GLB,Ca,and P in the serum of the three experimental groups were not significant(P>0.05).On the 30th day of the experiment,the BUN content in the green agent group and the fragrance agent group was respectively lower than the control group by36.19%and 41.79%(P<0.05).(2)In the fasting conditions on the 15th and 30th days of the experiment,there was no significant difference between the NPY and 5-HT levels in the serum of the experimental groups and the control group(P>0.05);on the 15th and 30th day of the test,1 h after food intake,the levels of NPY and 5-HT in the serum of the experimental groups were not markedly different from those in the control group(P>0.05).Conclusion:(1)The three kinds of attractants can significantly increase the average dry matter intake of calves,and the green agent treatment group and sweetener treatment group can also respectively increase the average daily gain of Angus calves,but the attractants had no significant effect on body measurements.(2)The addition of green pigment to diets can markedly increase the apparent metabolic rates of Ca,P,ADF,and NDF in calf diets;both flavoring and sweeteners significantly increased the efficiency of nitrogen digestion and utilization in calves.(3)The attractant can improve the immune performance of Angus calves,increase their disease resistance,markedly improve serum BUN levels,and effectively affect the level of serum hormone NPY and5-HT levels to control animal feeding.