Milk-feeding maintains the prochymosin production in cells of bovine abomasal mucosa.

The effect of milk-feeding on the development of prochymosin-producing cells in bovine abomasal mucosa was studied using immunochemical methods. As long as the calf was fed milk both mucous neck, and chief cells in the gastric glands, were immunoreactive for prochymosin, the precursor form of a specific milk-clotting enzyme. After weaning, the prochymosin immunoreactivity in chief cells in the lower base of the gastric gland declined and finally disappeared. Mucous neck cells and chief cells in the upper base of the gland, however, continued to be immunoreactive for prochymosin. All these cell types contained pepsinogen immunoreactivity both before and after weaning. Exposure to milk components thus seem to be of importance for the production of prochymosin in the abomasal mucosa. The present findings suggest that dietary components influence the cell differentiation in the gastrointestinal mucosa.