Histological cross section of the esophagus in neonate guinea pig shows 1. Lumen (L), mucosa (M), submucosa (Sm), muscularis mucosa (me), and adventitia (Ad). X4, H&E stain. 2. Keratin layer (K), Stratified squamous epithelium (E), muscularis externa (Me), Submucosa (Sm), and muscularis mucosa (Mm). X10, H&E stain. 3. Mucosa (M), epithelium (E), stratum corneum(1), stratum granulosum(2), stratum spinosum (3). X40, H&E stain. 4. Lamina propria (Lp), collagen fibers )Cf). X4, Masson’s trichrome stain. 5&6. Keratin layer (K), Stratified squamous epithelium (E), collagen fibers)Cf), Lamina propria (Lp), muscularis mucosa (Mm), and muscularis externa (Me) three layers1,2,3. X40, Masson’s trichrome stain. 7&8. No esophageal glands. X10, Alcian blue and PAS stains.