[Optical and scanning electron microscopic study of the structural development of the cecum and colon walls in the rabbit (Oryctolagus cuniculus L.) during the perinatal period].

The study, through optical and scanning microscopy, of various developmental stages, from the 24th day of gestation to the 13th day after birth, shows a quick development of the structures of the caecal and colic mucosal layers to the adult forms, from the very first week of postnatal life. The distal part of the colon is full-grown before the other parts of the alimentary canal, and is particularly rich in mucous cells. The caecum is the place where an early lymphoid defense is provided, from the 30th day of gestation.