The Diversity And Volatile Fatty Acids Were Found In The Biorectic Environment The Effects Of Serum Cerebral Peptides And The Effects Of Peppermint Extract On Its Regulation Were Studied

Partial thermal environment have a negative impact on physiology,behavior,substance metabolism,intestinal microflora and production performance of broiler.But there is no clear conclusion about the occurrence and regulation of moderate environment.In this project,we studied the effects of partial thermal environment on serum brain gut peptide,cecal volatile fatty acids and microbial diversity in broilers,and the regulation effect of peppermint extract,so as to provide theoretical basis for the mechanism research and establishment of regulation technology.This project simulates different thermal environment modes which included the daily cycle variation of the moderate temperatures and the constant moderate temperatures.The changes of serum brain peptide,cecal fatty acid and caecum microflora diversity in broilers were observed and investigate the regulatory effect of peppermint extract.The main contents are summarized as follows:1.The content of Serum 5-HT increased significantly and the content of serum VIP decreased significantly at the daily cycle variation of the moderate ambient temperatures,but but there was no significant effect on SP in broilers;(2)The bacteria bands and cecal microflora diversity at the daily cycle variation of the moderate ambient temperatures declined;The daily cycle variation of the moderate temperatures was beneficial to the growth of Parabacteroides,johnsonii and Bacteroides dorei,and inhibited the colonization of Intestinimonas butyriciproducen and Subdoligranulum variabile.2.The content of serum 5-HT and VIP in broilers at 31℃ decreased,and no significant difference was found for SP;The content of caecal butyric acid in broilers at 31℃ was significantly higher than that in 21℃,and the constant moderate temperatures had no significant influence on the contents of caecal acetic acid,propionic acid,butyric acid,valerate,nor valerate in broiler chickens;The bacterial bands number,similarity and diversity index of caecal bacteria in broilers at 31℃ was significantly lower than that in 21℃.The group of 31℃ was not conducive to the colonization of Clostridium termitidis and Bacteroides vulgatus.3.The content of serum 5-HT increased in 75 mg/kg mint extract add group while decreased the content of serum 5-HT in 300 mg/kg mint extract add group under moderate temperature,and during the whole experiment of mint extract had no sicant effect on serum VIP and SP in broilergnifis.In 300 mg/kg mint extract add group,the content of butyric acid in the caecum of broilers increased,but other treatment groups had no significant influence on the volatile fatty acids in the caecum of broilers.The control group Shannon index decreased significantly,the three treatment groups showed an upward trend in 75 mg/kg group,150 mg/kg group and 300 mg/kg group;the cecal flora richness of broiler in 300 mg/kg group increased;the cecal microflora specific bands of broiler in 225 mg/kg group and 300 mg/kg group were Lutispora thermophila,Faecalibacterium prausnitzii and Gemmiger formicilis belong to bacillus.To sum up,the daily cycle variation of the moderate ambient temperatures and constant moderate temperature could affect the serum levels of 5-HT and VIP in broilers,and the effects were different with the increase of Broilers age.The constant moderate temperature had influence on the content of cecal butyric acid in broilers.the daily cycle variation of the moderate ambient temperatures and constant moderate temperature affected the structure and diversity of caecal microflora in broilers.Mint extract can change the content of serum brain gut peptide and cecal volatile fatty acids,increased broiler cecal flora richness and similarity,and then change the caecal microflora.