Table 1.

Similarities and differences of chicken small intestinal epithelium compared with mammals.

Cell Types	Similarities	Differences
		Chicken	Mammal
Enterocytes	Polarized columnar cells along the villus with nutrient absorptive ability [26,27,28]
Paneth cells		Whether presented in the crypts is still controversial; could be distributed along the villus, or in the crypt [29,30]	Acidophilic granulocytes that are located in the crypt and interspersed with stem cells [19,24]
Goblet cells	Mucus-secreted cells that are distributed along the villus and in the crypt [31]
Stem cells		Located in the crypt but not interspersed with Paneth cells [22]	Distributed in the crypt with Paneth cells inserted [19,24]
Enteroendocrine cells	Minor cell population along the crypt-villus axis, secreting important hormones related to digestibility and feed intake [32]
Proliferation zone		Intensively identified in the crypt, but still detected along the villus [6,20]	Constraint in the crypt