Effects Of Butyric Acid Added To Acidified Milk On Growth Performance,Digestive Function And Weaning Stress Of Calves Under Different Feeding Modes

The effects of butyric acid on calf growth performance,digestive function and weanling stress were studied in this paper.The purpose of this study was to study the mechanism of butyric acid on calves,to determine the appropriate amount of butyric acid,and to provide scientific theoretical basis for the rational research and development of acidified milk and butyric acid and the application of calves.Experiment one.Effect of butyric acid added to acidified milk on growth performance,digestive function and weaning stress of calvesThe purpose of this study was to study the effects of butyric acid on the growth performance,digestive function and weanling stress of calves in acidified milk,and to explore the mechanism of its action and to screen out the appropriate amount of butyric acid.According to the principle of the average age distribution,18 calves were divided into 3 groups,6 calves in each group,and the control group was fed with acidified milk without butyric acid.The experimental group 1 was fed with butyric acid of acidified milk +0.3%,and 2 of the experimental group was fed with acidified+0.6%butyric acid,in which the feeding and feeding conditions were all the same.The results were as follows:(1)at the age of 30,the chest width of the 1 calves in the 1 groups was significantly higher than the control group(P<0.05).At the age of 55,the chest circumference of the 1 calves was significantly higher than the control group(P<0.05);the daily weight gain of the 1 and 2 calves in the whole feeding period was significantly higher than that of the control group(P<0.05);30~55 When D and 5-55D,the average daily feed intake of calves in the 1 and 2 groups was significantly lower than that in the control group(P<0.05),and the diarrhea rate of calves in the 1 and 2 groups was significantly lower than that in the control group(P<0.05),and the diarrhea rate of the 1 calves was the lowest.(2)the stomach chamber weight and the rumen nipple length and the length of the rumen nipple were added to the calves with different content of butyric acid in the acidified milk.The length,width,thickness of mucous membrane,thickness of muscularis,thickness of mucous membrane of jejunum,thickness of muscularis and muscularis thickness of ileum were significantly increased(P<0.05)in the 1 and 2 groups of calves,and the v/c ratio of duodenum,jejunum and ileum in 1 groups of calves was tested.The values were significantly higher than those in the control group(P<0.05),and the depth of duodenal crypt was significantly lower than that in the control group(P<0.05).(3)after calves weaned,the daily weight gain of calves in the 1 and 2 groups was significantly higher than that in the control group(P<0.05).At the age of 5 days after weaning,the total cholesterol content in the serum of 1 and 2 calves was significantly lower than that of the control group(P<0.05);the content of blood glucose in the serum of 2 calves was significantly higher than that in the test 1(P<0.05);and the test 2 calf blood was 2.The content of calcium in the serum was significantly higher than that of the control group(P<0.05),which was significantly higher than that of the test 1(P<0.05);the content of phosphorus in the serum of 2 calves was significantly higher than that of the test group(P<0.05).At the age of 10 days,the content of urea nitrogen in the calf serum of 1 and 2 groups was significantly lower than that of the control group(P<0.05);IgA,IgG,I before and after weaning.The content of gM in the serum of calves in each test group was not significant(p>0.05).When the age of weaning was 10 days old,the content of GH in the calf serum of 1 and 2 groups was significantly higher than that of the control group(P<0.05),and the content of SOD,T-AOC,CAT and ACTH in the calf serum of each test group had a rising trend,and the difference was not significant(p>0.05).At the age of 5 days after weaning,the content of MDA in the serum of 2 calves was significantly lower than that of the control group(P<0.05).At the age of 10 days after weaning,the content of CAT in the serum of 1 and 2 calves was significantly lower than that of the control group(P<0.05),and the content of COR in the serum of 1 and 2 calves was significantly lower than that of the control group(P<0.05).The above results were summarized as follows;(1)butyric acid in acidified milk can increase daily gain,reduce diarrhea rate,reduce feed to meat ratio and improve production performance.(2)adding butyric acid in acidified milk can improve the length and width of small intestinal villi,reduce the depth of recess,increase the v/c value,improve the thickness of small intestinal mucosa and muscularis,and improve the digestive function.(3)butyric acid in acidified milk can relieve weaning stress.(4)the optimum addition amount of butyric acid in acidified milk is 0.3%.Experiment two.Effect of free acidified milk on growth performance and diarrhea rate of calvesThe aim of this experiment was to study the effects of acidified milk on daily gain and diarrhea rate of lactating calves under free drinking conditions.According to the principle of average age distribution,70 healthy calves were divided into 3 groups,which were the traditional feeding group(control group),formic acid acidified milk group(formic acid group)and solid acid acidified milk group(solid acid acidified milk +0.3%d).The number of calf head was 20,20 and 30 respectively.Formic acid group and solid acid acidified milk group were fed with formic acid yoghurt and solid acid acidified milk(butyric acid +0.3%of solid acid acidified milk)with calf feeding device,and normal milk was fed in the control group.The feeding and feeding conditions were the same.The results were as follows:(1)the daily gain of calves in the solid acid group and the formic calves increased significantly(P<0.05),and the daily gain of calves in the solid acid group was significantly higher than that of the formic calves(P<0.05).(2)the diarrhea rate of calves in the solid acid group and the formic acid group was significantly lower than that of the control group(P<0.05),and the diarrhea rate of calves in the solid acid group was significantly lower than that of the formic calves(P<0.05).(3)the fixed acid group reduced the cost per weight 1kg of calves,and the results showed that the acidified milk could promote the growth of calves,reduce the diarrhea of calves,and improve the feeding efficiency of calves.Experiment three.Effect of ration supply of acidified milk on growth performance,diarrhea rate and labor intensity of calves.The aim of this experiment was to study the effects of acidified milk on daily gain,diarrhea rate and labor intensity of lactating calves under the condition of ration supply.According to the principle of average age distribution,68 calves were divided into two groups,which were the experimental group and the control group.The experimental group was fed with acidified milk(acidified milk +0.3%butyric acid),and the control group was fed with regular milk,in which the feeding and feeding conditions were all the same.Results:(1)the daily gain of calves of acidified milk group was significantly higher than that of control group(P<0.05),and the diarrhea rate of calves decreased significantly(P<0.05).(2)the acidification milk group reduced the working hours of the workers,saved the electricity charges of heating the milk and the water charges for cooling the milk,and reduced the cost of feeding calves.To sum up,feeding acidified milk can improve calfs growth performance and health status,and reduce the cost of rais:ing.The above results are summarized as follows:(1)Adding 0.3%butyric acid to the acidified milk can increase the daily weight gain of the calf,promote the development of the small intestine,improve the digestive function,and relieve weaning stress.(2)Free drinking and quantitative supply of acidified milk added with butyric acid can increase the daily gain of calves,reduce the labor intensity,and improve the efficiency of weight gain.Among them,acidified milk increased the daily gain of calves by 55%due to enhanced feeding(free drinking),and 45%caused by improved digestive function.