Effect of honeybee race and worker age on development and histological structure of hypopharyngeal glands of honeybee.

Development of hypopharyngeal glands (HPG) of native honey bee workers (Apis mellifera jemenitica) and Carniolan hybrid bees reared under normal constipations was studied. The HPG development degree and acini surface were influenced with age. The development degrees increased gradually. The maximum developmental degree was recorded at 9-days old in both two races. The development decreased after 12 days. The HPG development degree and acini surface of all ages in native bees were significantly less than Carniolan hybrid bees. Histological studies on HPG showed that there were some differences between the glands of the two races at the maximum developmental stage (9-days). The staining of cell cytoplasm by haematoxylin and eosin was similar. However secretory cells numbers were more in Carniolan hybrid than the native one.