Research On The Difference In Intestinal Microbiota And Its Key Metabolites Between Broiler Breeders With Different Egg Laying Level

The present study was conducted to compare the differences in intestinal microbiota and its key metabolites between broiler breeders with different egg laying level,to reveal the high egg laying performance related key-intestinal microbiota and metabolism pathway of broiler breeders.A total of 200 birds(41-wk-old)chosen from 5000 birds according to 2weeks’ egg laying performance were assigned to average reproductive group(AR)and high reproductive group(HR),with 10 replicates per group and 10 birds per replicate.Birds were fed with same diets without antibiotics,and the trial lasted for 42 days.The results are as follows:1)Compared with AR group,HR group has significantly higher egg production,acetic acid in duodenum,villus height/crypt deth in ileum,eggshell thickness,luminosity,redness,yellowness(P<0.01)value,and rate of setting egg at 6wk(P<0.05),but has significantly lower abdominal fat deposition,lower ALT(alkaline phosphatase)in serum,villus hight,in jejunum(P<0.05)and butyric acid in duodenum(P<0.01).2)Compared with AR group,HR group has significantly lower apoptosis rate(P<0.01),but has significantly higher Caspase 9,BMPR2,GATA4(P<0.05)and PRL-L(P<0.01)m RNA expression.3)Compare with AR group,HR group has significantly lower OTUs,Chao1,ACE index in ileum(P<0.01),Chao1 and ACE index in vagina(P<0.05).Dominant bacteria at phylum level of AR & HR groups are firmicutes(70.97% &73.92% respectively)and proteobacteria(19.73% & 14.78% respectively)in duodemun,firmicutes(71.12% & 73.30% respectively)and cyanobacteria(21.73% & 16.34%respectively)in jejumun,firmicutes(75.58% & 72.28% respectively)and cyanobacteria(11.73% & 16.07% respectively)in ileum,firmicutes(48.44% & 38.79% respectively)and bacteroidetes(45.09% & 41.76% respectively)in cecum,firmicutes(49.62% & 18.38%respectively)and proteobacteria(42.31% & 29.47% respectively)in cloaca.In AR group,firmicutes(36.10%)and proteobacteria(30.18%)are dominant bacteria in vagina,in HR group,firmicutes(38.15%)and bacteroidetes(34.78%)are dominat bacteria in vagina.Dominant bacteria at genus level of AR & HR groups are lactobacillus(64.92% &70.22% respectively)helicobacter(9.38% & 7.95% respectively)and phyllobacterium(9.15% & 5.08% respectively)in duodemun,lactobacillus(19.12% & 9.73% respectively),fusobacterium(14.03% & 11.21% respectively)and bacteroides(11.11% & 17.97%respectively)in vagina,phyllobacterium(23.44% & 9.06% respectively)and bacteroides(11.34% & 21.72% respectively)and fusobacterium(7.61% & 6.54% respectively)in cloaca.In AR group,lactobacillus(63.37%),phyllobacterium(1.61%),veillonella(1.23%)in jejunum,lactobacillus(61.54%),bacteroides(3.83%),phyllobacterium(2.60%)in ileum,lactobacillus(25.65%),rikenellaceae＿RC9＿gut＿group(5.63%),fusobacterium(2.90%)in cecum.In HR group,lactobacillus(69.22%),phyllobacterium(1.70%),helicobacter(5.16%)in jejunum,lactobacillus(56.54%),bacteroides(2.19%),brachyspira(1.60%)in ileum,lactobacillus(23.64%),rikenellaceae＿RC9＿gut＿group(3.83%),lactobacillus(2.9%)in cecum.4)Correlation bewteen dominant bacteria with reproductive performance:Bacteria in small intestines,at phylum level,cyanobacteria is negative Caspase9 m RNA expression(Caspase 9),euryarchaeota is negative to laying rate(La R),hatching rate(Ha R)and is positive to feed conversion rate(FCR).At genus level,lactobacillus is positive to Caspase 9,phyllobacterium is negative to La R and FCR.Bacteria in cecum,at phlyum level,bacteroidetes is negative to BMPR1 B and GATA4 m RNA expression(BMPR1B)(GATA4).firmicutes is positive to BMPR1 B and GATA4,fusobacteria is negative to PRL-L m RNA expression(PRL-L),spirochaetes is positive to FCR.At genus level,lactobacillus,helicobacter are positive to Caspase 9,BMPR1 B,GATA4 and PRL-L,fusobacterium is negative to PRL-L.Bacteria in genital tract,at phylum level,firmicutes is negative to BMPR1 B,bacteroidetes is positive to La R,tenericutes is negative to La R,FCR,follicle cells apoptosis(Apo CR),verrucomicrobia is negative to FCR and positive to Caspase 9.At genus level,helicobacter is positive to La R,BMPR1 B and PRL-L,bacteroides is positive to La R but negative to FCR.8)Metabolites: Compare with AR group,Octadecanoic,acid,11-trans-Octadecenoic acid,9,12-Octadecadienoic acid,d-Ribose,inositol in ileum are significantly higher.Inositol in ileum is significantly lower.Metabolites in ileum are involve in Phototransduction-fly,Fatty acid biosynthesis pathways,Inositol phosphate metabolism and Phosphatidylinositol signaling system.Metabolites in cecum are involve in Inositol phosphate metabolism and Phosphatidylinositol signaling system pathways.Collectively,there are more nutritions thansfering to laying egg,less fatty deposits and higher feed utilization rate in the higher reproductive breeder.Euryarchaeota,phyllobacterium and planctomycetes are against to reproduction,which are negtive to La R,FCR.Firmicutes,lactobacillus and helicobacter are contribute to reproduction,which are positive to BMPR1 B and GATA4.Octadecanoic acid and inositol involving in relative metabolites pathways could effect the secretion of hormone,deposition of nutrients and proliferation and apoptosis of cells,which could improve the reprodution of broiler breeders.