Changes in the salivary glands of female Hyalomma (Hyalomma) dromedarii during and after feeding.

The salivary glands in female H. dromedarii consists of three alveolar types, one agranular (type I) and two granular (type II and III). Five granule secreting cell types were identified according to their granular submicroscopic appearance. The structure and changes observed in type I alveoli before, during and after feeding suggest its role in ion and water transport from the haemolymph to the lumen during initial feeding. Secretory cells in salivary alveoli types II and III undergo substantial growth, differentiation and accumulation of secretory material during feeding and various rates of depletion directly after feeding. Attachment and limited feeding seems to provide a stimulus for synthesis of proteins, lipids and carbohydrates, whereas detachment from the host decreases the secretory competence of these alveoli causing its degeneration.