Differential mRNA expression of nutrient transporters in male and female chickens

Male chickens grow faster than female chickens, which may be due to greater nutrient uptake. The transport of nutrients from the intestine to the blood is mediated by transporters located on the surface of epithelial cells lining the villi. The objective of this study was to profile the mRNA expression of an aminopeptidase and selected amino acid and monosaccharide transporters in the duodenum, jejunum, and ileum of male and female chickens at d of hatch (doh) and at d 7 and d 14 post hatch. The mRNA abundance of aminopeptidase N (APN), a peptide (PepT1), 6 amino acid transporters (ASCT1, b(o,+) AT, CAT1, EAAT3, LAT1, and y(+)LAT2), and 3 monosaccharide (GLUT2, GLUT5, and SGLT1) transporters was assayed by real-time PCR. Data were analyzed by ANOVA using JMP Pro11. The abundance of b(o,+) AT, EAAT3, ASCT1, y(+) LAT2, and GLUT2 mRNA was greater in male than female chickens (P < 0.05). There was no difference in expression between males and females for the other 5 transporters and APN. There was a sex x age interaction for b(o,+) AT, PepT1, SGLT1, ASCT1, and y(+) LAT2 mRNA, with greater mRNA abundance in males than females at doh but no difference between males and females at d 7 and d 14. A 3-way sex x age x tissue interaction was observed for GLUT2 mRNA. There was greater GLUT2 mRNA abundance for males in the duodenum and ileum at doh and in the jejunum at d 7, but no difference between males and females at d 14. Thus, there was differential expression of some nutrient transporters in male and female chicks at doh but not at later ages.