Study On The Phytovorous Food Composition,Gut Bacteria And Parasitic Diversity And Their Relationship Of Grus Grus During Overwintering In Caohai,Guizhou

Animal gastrointestinal tract contains a variety of microorganisms,which play an important role in maintaining animal health,nutrition and physiology.Among them,gut bacteria play an important role in substance synthesis and metabolism,resistance to pathogen invasion and immune regulation.Intestinal parasites can cause host physiological dysfunction and even death in severe cases.Host gut bacteria and parasites are mainly derived from individual feeding and environmental factors,and food factors are considered to be one of the main factors causing the differences in intestinal microbial structure of birds.Due to the complex habitat environment,it is difficult for wild birds to distinguish the composition of feeding food by traditional methods.Moreover,during the overwintering period,G.grus is mainly dominated by plant food.In this study,the high-throughput sequencing technology based on chloroplast rbc L gene was used to study the phytophagous food composition of the national secondary key protected bird G.grus during the overwintering period in the Caohai,sanger sequencing method was used to re-confirm the collected feces of G.grus,so as to avoid the inaccuracy of the results caused by the confusion of feces of Grus nigricollis,Tadorna ferruginea and Anser indicusin in the same domain.At the same time,this study used high-throughput sequencing technology based on 16 S V3-V4 and18 S V4 regions to determine the gut bacterial and parasitic infections of G.grus.By analyzing the differences of food composition,gut bacteria function and parasites infection types in different sampling points,the relationship among food,bacteria and parasites was established,and the effects of food factors on intestinal health of G.grus were discussed.The results show that :1)There was no correlation between the diversity of phytophagous food,gut bacteria and parasites and the number of analytical samples of G.grus;2)The diversity of phytophagous food composition affects the diversity of intestinal bacterial composition.Caohai G.grus phytophagous food is mainly crops,supplemented by wild food.Gut bacteria at phylum level include Proteobacteria,Firmicutes,Actinobacteria and Bacteroidetes.When the food composition is rich,the gut bacteria that decompose the corresponding food are also abundant,and their functional expression is also high.Food difference is an important reason for the structural change of gut bacteria;3)The intestinal flora of G.grus fed on high-fiber foods was mainly dominated by Proteobacteria,and the intestinal flora of G.grus fed on high-sugar foods was mainly dominated by Thick-Walled Fungi.The metabolic functions of carbohydrates,auxiliary factors and vitamins of Thick-Walled Fungi were higher than those of Proteobacteria,which fully reflected the adaptability of the structural differences of intestinal bacteria of G.grus to food;4)The diversity of phytophagous food was positively correlated with the diversity of gut bacterial composition and functional diversity,and negatively correlated with the diversity of parasite composition.This study provides a theoretical basis for the survival and protection of wintering G.grus by analyzing the composition of phytophagous food,gut bacteria and parasite infection.At the same time,the relationship between food and gut bacteria,parasites were shallowly analyzed,which provided an important basis and reference value for the study of wintering cranes and other birds in Caohai.