Relationship Between Egg Production Performance And Microbial Composition Of Laying Hens In Late Laying Period

Egg production performance is an important aspect of poultry farming,which is closely related to economic benefits and is regulated by external environment,endocrine and genetic factors.For the endocrine factors that regulate egg production,there are mainly some hormones such as gonadotropin-releasing hormone,prolactin,follicle-stimulating hormone and luteinizing hormone;Its genetic factors are mainly regulated by genes related to spawning performance.In recent years,the most important problem facing the laying hen breeding industry is how to extend the egg laying cycle of caged laying hens,improve the egg production performance of laying hens in the late stage of egg production,the variety selected in this paper Jinghong series has superior production performance,outstanding reproductive performance,practicality,strong adaptability and other advantages.In this study,by studying endocrine and genetic factors related to egg production performance,and analyzing the influence of intestinal microorganisms on egg production performance through fecal bacteria transplantation,this study seeks to improve egg production in order to improve the reproductive performance of laying hens and optimize the utilization efficiency of laying hens.The results of the study are as follows:By measuring the expression of genes related to egg quality and egg quality in the high and low egg laying groups at different times,the test results showed that there was no significant difference in the eggshell strength between 60 weeks and 64 weeks old in the high and low egg laying group,and both were significantly lower than those at 56 weeks old(P < 0.05).There was no significant difference in eggshell color between 60 weeks and 64 weeks of age,but both were significantly higher than those at 56 weeks(P < 0.05).At 64 weeks of age,the eggshell color of the high-laying group was higher than that of the low-laying group(P < 0.05).At 64 weeks of age,the expression of CPOX was significantly higher in the low-egg producing group than in the high-egg producing group(P < 0.05).Eggshell color was significantly negatively correlated with the expression of gene CPOX,and the correlation coefficient was-0.5954.In the microbial sequencing results,at the gate level,the dominant flora in the vagina and uterus of the 56-week-old and 64-week-old egg-laying groups were Firmicutes,Proteobacteria,Bacteroidetes,and Actinobacteria,accounting for about 70%.The results of PCA analysis showed that the differences in microbiota in and between groups were small in and between groups in the high and low egg laying groups at different times,and the results of ALPHA diversity showed that there were no significant differences in uterus and vagina in the high and low egg laying groups at different times.The analysis results of serum hormone content in high and low egg producing groups at different times showed that there were no significant differences in the contents of FSH,LH and E2 hormones in the high and low egg producing groups in the high and low egg producing groups.Through the comparative analysis of serum hormone content between high and low egg producing groups in different periods,the egg producing group with high FSH and LH content was significantly higher than that in the low egg producing group(P < 0.05)at 56 weeks and60 weeks of age,the high egg producing group with high LH content was significantly higher than the low egg producing group(P < 0.05)at 64 weeks of age,and the egg producing group with high E2 content at 56 weeks of age was also significantly higher than that in the low egg producing group(P < 0.05).The results of fecal bacteria transplantation showed that the dominant flora in uterus and vagina at the level of the four inner phylums were Firmicutes,Proteobacteria,Bacteroides,and Actinomycetes,and the dominant flora in the cecum were Firmicutes,Bacteroides,Campylobacter,Dethiobacillus and Deferendox.At the family level,the dominant flora in utero is Enterobacteriaceae,Trichobacterceae,and Alkaliogeneae,and the dominant flora in the vagina is quite different in the four groups,roughly the dominant flora is Tricholomaceae,Enterobacteriaceae,and Lactobacillaceae,while the dominant flora in the cecum is Bacteroides,Tricholomaceta,Spirosaceae,Spirosinidae,and Campylobacter.There was no significant difference in the alpha diversity of the vagina and uterus in the four groups,but all were significantly higher than those in the cecum(P < 0.05),there was no significant difference between the test group and the control group in the uterus and vagina,and the microbiota diversity in the cecum test group was lower than that in the blank control group(P < 0.05).In the experimental group,there were significant differences in the diversity of microbial BETA in the cecum between the individuals in the group(P < 0.05),the differences between the uterus and vagina were small,and the differences between the uterine and vaginal groups were small,but the differences between the two and the cecum were significant(P < 0.05).Among individuals in the blank control group,the diversity of beta in the uterus,cecum and vagina was small,and the difference between the uterus and cecum was small,but the difference with the cecum was significant(P < 0.05).After fecal bacteria transplantation,the serum contents of follicle-stimulating hormone,luteinizing hormone and estradiol in the experimental group were significantly higher than those in the control group(P < 0.05),and the high-laying hen experimental group was significantly higher than that in the low-egg producing group(P < 0.05).Only the content of E2 in the blank control group of the high egg laying group was significantly higher than that in the blank control group of the low egg laying group(P < 0.05),and there was no significant difference in the content of the other two hormones.The expression of GDF9 and FSH genes in the reproductive tract funnel of laying hens was significantly higher than that in the high egg laying test group,high egg laying blank control group and low egg laying blank control group(P < 0.05).There were no significant differences in the expression of the genes ESR and FSHR in the four groups.In conclusion,eggshell color is negatively correlated with the expression level of gene CPOX,and the higher the expression level of gene CPOX,the darker the brownish eggshell color.The microorganisms of uterus and vagina were similar to some extent,and the dominant bacteria were Firmicutes,Proteobacteria,Bacteroidetes and Actinobacteria.The microbial diversity of intestinal microbiome and tubal microbiome was different to some extent.Firmicutes and Proteobacteria were dominant in tubal microbiome,and Firmicutes and Bacteroides were dominant in intestinal microbiome.Fecal transplantation can affect the diversity of intestinal microflora in cecum.The effects of intestinal microorganisms on serum FSH and LH contents of high-yielding laying hens were stronger than those of high-yielding laying hens on low-yielding laying hens.