The Effects Of Baitouweng San On Performance,Immunity And Intestinal Microflora Of Laying Hens In Late Laying Period

The extensive use and abuse of antibiotics cause bacteria to develop multi-drug resistance,which poses a serious threat to food safety and public health.Under the environment of prohibition and restriction of antibiotic resistance,the prevention and control of poultry bacterial diseases poses a major challenge to the green and healthy development of poultry industry.The immune function of laying hens in the late stage of laying leads to the decline of production performance and the occurrence of diseases,which greatly reduces the economic benefit.Therefore,it is urgent to develop green and efficient substitute products to improve the physiological function and economic benefit of laying hens.Baitouweng San has anti-inflammatory,antibacterial,immune function enhancement,anti-parasite,liver protection and other functions.It is widely used in clinic,but the application procedure is chaotic.The purpose of this paper is to study the clinical effect of Baitouweng San on laying hens in the later stage of production,explore the application procedures of Baitouweng San,and provide a basis for the clinical application of Baitouweng San under the background of reducing resistance and limiting resistance.The 60-week-old Dawu Jinfeng laying hens were divided into control group,Radix Pulmonae pulmonae powder single administration group and cyclic administration group.The effects of Pulsatilla powder on performance,immune function and intestinal health of laying hens in late laying period were determined.The test results were as follows:1 Baitouweng San can improve the production performance and enhance the metabolic capacity of laying hens in the late laying period.During the feeding cycle,compared with the control group,the laying rate and average egg weight in the single administration group were significantly increased（P<0.05）,the feed to egg ratio was significantly decreased（P<0.05）,and the laying rate in the circulating administration group was significantly increased（P<0.05）.Serum total superoxide dismutase activity was significantly increased in both single administration group and circulating administration group（P<0.05）,and serum contents of triglyceride and glutamic oxalacetic transaminase were significantly decreased（P<0.05）,and total cholesterol content was significantly decreased in single administration group（P<0.05）.2.Feeding Baitouweng San once a month can improve the immune function of spleen in later period of laying hens.The expressions of immune factors J-CHAIN,INF-γand AVBD2 in single administration group were significantly up-regulated（P<0.05）,and the ratio of CD₄⁺/CD₈⁺was significantly higher than that in control group on day 26（P<0.05）.Only the expression of Caspase-3 in the circulating medication group was significantly higher than that in the control group（P<0.05）,and the CD₄⁺/CD₈⁺ratio was not different from that in the control group.3.Baitouweng San can enhance intestinal barrier function,increase the abundance of beneficial bacteria in cecum of laying hens,and reduce the abundance of harmful bacteria in laying hens.Compared with control group,the genes of Claudin-1,Occludin,ZO-1,ZO-2 and Muc2 encoding tight junction proteins of duodenum,jejunum and ileum in single administration group and circulating administration group were significantly up-regulated（P<0.05）;On day 56,many genes coding for tight junction protein were significantly lower in the cyclic medication group than in the single medication group（P<0.05）.The results showed that the single administration group was superior to the circulating administration group in increasing the expression of intestinal compact junction protein and enhancing the function of intestinal barrier.Effect of Baitouweng San on cecal microflora diversity of laying hens in late laying period.On the 6th day,the relative abundance of beneficial bacteria（Firmicutes）increased,the relative abundance of Actinobacteria decreased,the ratio of Firmicutes to Bacteroides（F/B）increased,and the species abundance of Lactobacillus showed an increasing trend（P=0.063）.The species abundances of Subdoligranulum,unclassified＿f＿＿Lachnospiraceae and Olsenella were significantly decreased（P<0.05）.On day 56,the relative abundance of Firmicutes increased in both the single administration group and the circulating administration group,while the relative abundance of Bacteroidetes and Actinomycetes decreased in both groups,and the F/B value increased in both groups.The species abundance of Lactobacillus was significantly increased（P<0.05）,and the harmful bacteria of rare Subdoligranulum and unclassified＿f＿Lachnospiraceae had a tendency to decrease（P>0.05）.The addition of Baitouweng San can increase the abundance of beneficial bacteria and decrease the abundance of harmful bacteria in cecum of laying hens.In summary,the supplementation of Baitouweng San in the diets of laying hens in the late laying period can improve the levels of glucose metabolism and lipid metabolism of laying hens in the late laying period,improve the immune and antioxidant functions of the body,enhance the mucosal barrier function of the small intestine,and have no effect on the diversity of cecum flora,but can increase the relative abundance of beneficial bacteria Lactobacillus,thus improving the production performance of laying hens in the late laying period.And the effect of single dose group was better than that of circulating medication group.