Fig. 2

ALNA of Bactrian camel fetus at 7 months of gestation. a The ALNA (yellow oval area) mucosal structure of the fetus at 7 months of gestation is relatively clear, and the mucosal fold is higher and thicker than the surrounding non-ALNA. It is mainly composed of RMFR, and the LMFR fold structure is not significant. b At low magnification, lymphocytes can be seen in the Submucosa and muscularis mucosa, which are more and more dense than those at 5 months of gestation. H&E stain, Scale bar 200 μm. c The mucosal epithelial cells here are monolayer columnar epithelial cells (black arrows), with a small number of intraepithelial lymphocytes (red arrows). H&E stain, Scale bar 20 μm. d In the submucosa and muscularis mucosa, some deeply stained lymphocytes (black arrows) were dispersed around the reticular epithelial cells (red arrows), but there was still no formation of lymphoid follicles. H&E stain, Scale bar 20 μm