HISTOCHEMISTRY OF THE FORESTOMACH EPITHELIUM OF THE REINDEER CALF

Samples from the rumen, reticulum and omasum of 26 reindeer calves wer e taken during the winter season. Non-specific alkaline and acid phosp hatases, cytochrome and amine oxidases as well as succinate, lactate a nd 3-hydroxybutyrate dehydrogenases were demonstrated in the epitheliu m histochemically. The phosphatases were usually present in all the ep ithelial layers, whereas the activities of the other enzymes decreased in the outer layers and could not be demonstrated in the stratum corn eum. The activity of alkaline phosphatase seemed to be highest in the reticulum and lowest in the omasum. The reason for the higher activity of this enzyme in epithelial taps in the rumen and omasum and in the reticular and omasal papillae may be the greater need for effective ve rtical transcellular transport in these regions. There was a tendency for enzymes other than phosphatases to be more active in the rumen tha n in the other forestomachs, which probably reflects the higher metabo lic activity of the ruminal epithelium. No clear differences between e arly and late winter could be demonstrated.