Effects Of Different Levels Of Dietary Arginine On Gene Expressions Of Nutrient Transporters And Digestive Enzymes In Small Intestinal Mucosa Of Progeny Of Haidong Breeder Chickens

To investigate the effects of dietary arginine supplementation at different levels on gene expression of nutrient transporters(PepT1,SGLT1,GLUT2)and digestive enzymes(APN,SI)in small intestinal mucosa of Haidong chicken.The 440 breeding chickens were divided into 10 groups,4 replicates per group(male to female ratio1:10).The first 5 groups were supplemented with 0.96%,1.16%,1.36%,1.56% and1.76% L-arginine on the basis of 3000 IU vitamin D3,respectively;The other 5groups were supplemented with 0.96%,1.16%,1.36%,1.56% and 1.76% L-arginine on the basis of 5000 IU vitamin D3,respectively.The chickens were raised for 44 days.Samples were taken at 18 and 20 days of embryonic age,and at 1 and 7 days of early stage,The samples were duodenum,jejunum,ileum,yolk sac and yolk sac membrane.The results show that: in terms of the impact on production performance,the1.16% arginine level of 5000 IU vitamin D3 in Haidong breeders diet could significantly increase laying weight(P<0.05),Vitamin D3 level of 5000 IU can significantly improve the egg weight(P<0.05).In terms of gene expression,As the embryo develops into a chick,The relative expression levels of target genes PepT1,GLUT2,SGLT1,APN and SI tended to transfer from yolk sac to intestinal tract,It accords with the change of nutrient digestion and absorption state of chick growth and development.The relative expression levels of nutrient transporters and target genes of digestive enzymes in different parts of Haidong chicken were significantly different(P<0.05).The relative expression level of PepT1 mRNA in the intestinal tract of embryos and chicks decreased as the intestinal segment moved backward;The relative expression level of GLUT2 mRNA increased with the intestinal segment moved backward;The relative expression level of APN mRNA was the highest in jejunum and the lowest in duodenum;The relative expression levels of SGLT1 and SI mRNA were the highest in jejunum and the lowest in ileum.The mRNA expressions of intestinal nutrient transporters PepT1,GLUT2,APN,SGLT1 and SI were analyzed.It was concluded that the level of vitamin D3 at 3000 IU and the level of arginine at 1.16% significantly increased the gene expressions of intestinal nutrient transporters and digestive enzymes in chicks.The mRNA expression levels of nutrient transporters PepT1,GLUT2,SGLT1 and digestive enzymes APN and SI in Haid ONG chickens were different in location and arginine level,but there was no significant difference in vitamin D3 level.According to the comprehensive analysis of the above indexes,in order to achieve low input and high production performance,the gene expression of the overall nutrient transporter and digestive enzyme have the best influence.It is suggested that the supplemental level of arginine and vitamin D3 should be1.16%-1.36% and 3000 IU in the diet of Haidong breeder chickens.