Effects Of Hybridization On Slaughtering Performance And Intestinal Microbial Diversity In Chicken

Heterosis can be established by taking advantages of epistatic effect and interaction effect between genes,and the production performance and economic benefit of livestock and poultry can be improved by using heterosis.Crossbreeding is the main way to breed new breeds of livestock and poultry.Through breeding excellent breeds,strains and individuals,we can breed the hybrids that meet the breeding requirements.Hybridization is usually used to improve the quality of livestock products.Especially in broiler breeding,crossbreeding is more common.Through the mating and reproduction of different breeds,new commercial lines will be produced,which will bring huge economic benefits.The gut of mammals contains a large number of bacterium and a little of other microorganisms,such as fungi,archaea and viruses.Among them,99%of the intestinal microorganisms are bacteria,which are closely related to the health and disease of the host.The change of the type,number and proportion of normal intestinal flora can significantly affect the adaptive immune response of the intestine.The microbiota is different among chickens with various genetic background,however,the influence of hybridization on intestinal microbiota is less studied.In the current study,five pure lines were selected as parents to cross,and five hybrid offspring groups were obtained.All the chickens were raised under the same condition with free access to feed.Chickens were slaughtered on 70 days old,slaughtering performance was measured,the DNA samples was isolated from cecal contents for 16S r RNA sequencing.The results showed that,1 Effect of crossbreeding on slaughter performance and meat quality:B₃was the best group.From the relative growth rate of body weight,A₄,B₃,AB₃A,A₂B₂A,A₂B₃A groups were better;percentage of half eviscerated yield and percentage of eviscerated yield in A₄,B₃,A₂B₃A,A₄B₃A groups were better and was more than 90%in all groups.Percentage of half eviscerated yield in the A₂B₂A group was 74%,more than 90%in other groups.The percentage of eviscerated yield in all groups was 60%～70%.All groups in this experiment had good performance of the meat production performance.For the weight of the shank and claw,breast muscle and leg muscle,A₂,A₄,B₂,B₃and AB₃A had better performance than the others.The p H values of all groups were between 5.5 and 5.75.The tenderness of A₄,AB₃A and A₂B₃A groups was greater,and the cooking loss rate of B₃,A₂B₂A and A₄B₂A groups was the lowest;the skin color of A₂,B₂and A₂B₃A groups was more bright red,giving people a feeling that the meat was more fresh.The meat color of group A was better than that of the other groups.From the carcass aesthetic degree,it can be seen that the aesthetic degree of group A,A₄and B₂was higher than that of the other groups.2 Effect of hybridization on intestinal microbial diversity:there were 3 different phylum,which were Bacteroidetes,Firmicutes and Proteobacteria.For the relative abundance of cecal microorganisms at family and genus level,A₄,B₃,AB₃A and A₂B₃A had higher intestinal microbial abundance.For the relative abundance heat map of cecal microbial community at family level,the abundance of bacteroidea was higher while firmicutes was lower in B₃,A₂B₂A and A₂B₃A groups.For the relative abundance of cecal microbial community at genus level,the abundance of Bacteroides in B₃,AB₃A,A₂B₂A and A₂B₃A was higher than that of Firmicutes.For the alpha diversity and beta diversity,A₄,B₃,AB₃A and A₄B₃A populations have good intra population biological repetition and can be distinguished from other populations.Among the relative abundances of different species at family level,the abundances of groups A,A₄,B₃and AB₃A were higher among the top ten groups at family level.COG analysis showed that the relative abundances of carbohydrate transport and metabolism,amino acid transport and metabolism,energy production and conversion,inorganic ion transport and metabolism,coenzyme transport and metabolism in groups A₄,B₃and AB₃A were higher.KEGG analysis showed that the relative abundances of metabolism,genetic information processing,cancer function genes and lipopolysaccharide biosynthesis function genes in groups B₃,A₂B₂A and AB₃A were lower,while the relative abundances of gastric acid secretion,splice body,complement and coagulation cascade,calmodulin ligand and pancreatic secretion function genes were higher.3 A₄,B₃,AB₃A,A₂B₃A group has better slaughtering performance and meat quality,higher intestinal microbial abundance,carbohydrate transport and metabolism,amino acid transport and metabolism,coenzyme transport and metabolism,relatively low abundance of biosynthesis,and gastric acid secretion and pancreatic secretion.4 At genus level,A and B₃co-affected microflora composition in AB₃A,B₂had a great impact on microflora composition in A₂B₂A.A₂had a greater impact on microflora composition in A₂B₃A.A4 had a greater impact on microflora composition in A₄B₂A.A₄had more influence on microflora composition in A₄B₃A.Comparing the groups with the same parents,the influence of paternal parents on the offspring was as follows:A₄>B₂>A₂>B₃>A.