Abstract
The goal of this study was to determine whether lysosomal hydrolase activity changes during induced molting in the hen pituitary. White Leghorn aged laying hens were subjected to induced molting by feed withdrawal. Gradual feeding was started on 4th d of egg-laying cessation. The anterior pituitaries were collected from hens of pretreatment, 3 d and 5 d after starvation, 3 d and 10 d after cessation of egg-laying (6 d after resumption of feeding), on day of and 7 d after resumption of egg-laying. They were processed for the detection of acid phosphatase (AcPase) activity by enzyme histochemistry. Sections were then examined under a light microscope with an image analysis computer system. The AcPase activity was observed in the cellular cytoplasm in both cephalic and caudal lobes of the anterior pituitary in all groups of hens. In the both lobes the positive area increased significantly in the group of 3 d after cessation of egg-laying when compared with pretreatment group. These results suggest that lysosomal enzyme activity in the anterior pituitary of chicken was enhanced a few days after cessation of laying, which may be responsible for the digestion of unusable hormonal granules at this phase.
