Effect Of Compound Traditional Chinese Medicine On Intestinal Immunity And Water Metabolism Related Factors In Broilers With Diarrhea Induced By Flunfenicol

Antibiotic-associated diarrhea(AAD)is the most common disease caused by intestinal flora imbalance after the application of antibiotics.The occurrence of AAD is mainly related to intestinal flora imbalance,immune dysfunction and imbalance of water and fluid metabolism.Florfenicol is a widely used feed antibiotic,and diarrhea is one of the common causes of abuse.Compound traditional Chinese medicine has effects of improving intestinal flora disturbance,improving body immunity and regulating water-wet metabolism,and has remarkable curative effect on diarrhea.Studies have shown that the TLR4/NF-κB pathway is involved in the regulation of intestinal immunity and barrier function,and AQP4 is closely related to intestinal water transport.The aim of this study was to investigate the changes of TLR4/NF-κB pathway-related factors and AQP4 in the intestinal tract of broilers induced by florfenicol and the effective prevention and treatment mechanism of compound traditional Chinese medicine on the diarrhea of broilers.Method:A total of 303 1-day-old Ross broilers were adaptively reared for 1 week before the test(feed-based feed),and the weak chickens were removed and randomly divided into five groups.The number of broilers in each group was 55.Blank group;florfenicol group(100 mg/kg?bwd florfenicol);compound traditional Chinese medicine high-dose group(fed with same florfenicol group + drinking water added 2 g/kg ?bw?d Compound Chinese medicine);compound Chinese medicine low-dose group(fed with same florfenicol group + drinking water added 1 g/kg ?bw?d compound traditional Chinese medicine group),L-arginine group(fed same with florfenicol group + diet added 1% L-Arg).At the 15 th,25th,35 th and 45 th day of broiler chicken weighing,the carotid artery was sacrificed by bloodletting,pathological changes were observed,the spleen and thymus were quickly taken out and weighed,and the organ index was measured.Two sections of tissue of about 1 cm in the duodenum,jejunum,and ileum were taken,one part was fixed in bouins for intestinal morphology examination,and the other part was quickly placed in liquid nitrogen and then transferred to a refrigerator at-80℃ for a long-term preservation.The fluorescence quantitative PCR were used to detect the relative expression of TLR4,My D88,NF-κB,TNF-α and AQP4 m RNA.Result:1.During the test period,compared with the blank group,the florfenic group broilers were weak,the feathers were unkempt,the feed intake were reduced,the drinking water increased,and there were yellow-white or light-green feces arounded the anus,and the drainage was loose;It can be observed that most of the intestinal tract was swollen,congested and even hemorrhagic.The intestinal wall was thin and translucent,the contents of the intestine are diluted,and some of the abdominal cavity can also be seen with acid odorous effusion.Compared with the florfenicol group,the clinical symptoms of the compound Chinese medicine and the L-arginine group were significantly improved.2.Compared with the blank group,the diarrhea rates of broilers aged 8-15,16-25,26-35 and 36-45 days were significantly increased(P<0.01);compared with florfenicol group The diarrhea rate of broilers aged 8-15,16-25,26-35 and 36-45 days in the high-dose group of compound traditional Chinese medicine decreased significantly(P<0.01 or P<0.05),the rate of diarrhea in the low dose of compound traditional Chinese medicine,L-arginine group(16-25,26-35,36-45-day-old)were significantly decreased(p <0.01).3.Compared with the blank group,the body weight,thymus index and spleen index of broilers at 15,25,35 and 45 days old were significantly decreased(P<0.01 or P<0.05);compared with florfenicol group The weight,thymus index and spleen index of broiler chickens in the high and low dose groups of compound traditional Chinese medicine were significantly increased(P<0.01 or P<0.05),and L-arginine group was 25,35,45 days old.The body weight of broilers increased significantly(P<0.05),and the spleen index and thymus index of broilers at 35 and 45 days of age increased significantly(P<0.01 or P<0.05).4.Compared with the blank,the relative expression levels of TLR4,My D88,NF-κB and TNF-α m RNA in the duodenum,jejunum and ileum of broilers in the florfenicol group were different in degrees 15,25,35 and 45 days increased,some showed significant(P<0.01 or P<0.05);compared with florfenicol group,compound traditional Chinese medicine high,low dose and L-arginine group at 15,25,35 and 45 days,the relative expression levels of TLR4,My D88,NF-κB and TNF-α m RNA in duodenum,jejunum and ileum of broilers decreased to some extent,and some showed significant(P<0.01 or P<0.05).5.Compared with the blank group,the relative expression of AQP4 m RNA in the duodenum,jejunum and ileum of the florfenic group was significantly decreased(P<0.01);compared with the florfenicol group,the relative expression of AQP4 m RNA in the duodenum,jejunum and ileum of the broilers in the high and low dose groups of compound traditional Chinese medicine was significantly increased(P<0.01 or P<0.05),and the relative expression of AQP4 m RNA in the duodenum,jejunum and ileum of the broilers in L-arginine group was increased significantly(P<0.01 or P<0.05).Conclusion1.Florfenicol induced diarrhea,the immune organ index significantly decreased.The relative expression of TLR4/NF-κB pathway-related genes TLR4,My D88,NF-κB and TNF-α m RNA in the intestinal tract was significantly increased,and the relative expression of AQP4 m RNA was significantly decreased,indicating that the TLR4/NF-κB pathway was involved in the development of flufenicol-induced diarrhea by regulating immune and water-metabolism-related factors and promoting intestinal mucosal damage.2.Compound traditional Chinese medicine and L-arginine effectively increased the immune organ index,down-regulated the relative expression of TLR4,My D88,NF-κB and TNF-α m RNA in the small intestine,and up-regulated the relative expression of AQP4 m RNA.The amount increased significantly,indicating that the compound Chinese medicine and L-arginine can regulate the body’s immune and water-liquid metabolism functions to effectively prevent florfenic-induced diarrhea.