【Animal Modeling】-Effects of experimental intervention of normal saline on caecal microflora and short-chain fatty acid content in broilers

  OBJECTIVE: To study the effects of experimental intervention of normal saline on the microflora and content of short-chain fatty acids in the caecum of broilers, in order to provide a theoretical basis for the study of early microbiota intervention experiments.

  Methods: 80 newly hatched chicks were selected and randomly divided into 2 groups, namely the control group (group C) and the normal saline group (group S). For the first 2 days after hatching, the chicks of the S group were given 0.5 per day for the first 2 days. mL sterilized normal saline, and group C did not receive any treatment. On the third day and the seventh day, 8 chickens were randomly selected from the two groups, their body weights were measured, and their caecal contents were slaughtered to obtain the contents of the cecum. The microflora structure of the cecal contents was determined, and the content of short-chain fatty acids in the cecal contents was determined by gas chromatography.

  Results: The experimental intervention of normal saline had no significant effect on the average daily gain of broilers in the early stage (P > 0.05). At the phylum level, the proportion of cecal flora in the two groups of broilers was basically similar. Proteobacteria and Bacteroidetes were the dominant bacterial phyla in the gut of early broilers. At the genus level, Bacteroides and Cyanobacteria_norank were found in the cecum of S group broilers at 3 days of age. Compared with the C group, the relative abundance of the genus was increased by 160% and 143% respectively (P<0.05); at the age of 7 days, there was no significant difference in the relative abundance of the cecal bacteria between the two groups. In addition, the experimental intervention of normal saline can be extremely significant The contents of acetic acid, butyric acid and isovaleric acid in the cecal contents of the 3-day-old broilers were decreased (P < 0.01), but the short-chain p="">0.05 in the cecal contents of the two groups of broilers at the 7-day age.

  CONCLUSION: The experimental intervention of normal saline has a certain effect on the cecal microflora structure and the content of short-chain fatty acids in 3-day-old broilers, but this effect is not persistent and will gradually disappear with the increase of the age.