Morphological and Anatomical Deformities of Hirudo verbana, Carena 1820 (Annelida, Hirudinea) After Feeding: Light and Electron Microscopic Analysis.

Leeches are widely used as model organisms in scientific studies and medical treatments. Medical leeches are hematophagous parasites that usually feed on the blood of their hosts. Some leeches show deformities, usually after feeding. This causes both medical and economic losses as it reduces the effectiveness of leeches in cultivation and medical treatment. The aim of this study was to investigate the effects of morphological deformations after feeding in Hirudo verbana, Carena 1820 (Annelida, Hirudinea), an important species in medical leech treatments. For this purpose, both histopathological and scanning electron microscopy examinations of starved and fed leeches were performed. The causes of deformities in medical leeches were found to be due to overfeeding, which caused cracks on the intestinal surface and therefore deterioration of the tissues. It is also thought that the immunological agents in the fed blood destroyed the medical leech tissue in these regions. In addition, it was determined that the cellular structure of the shaped blood elements stored in the cavity after feeding was preserved for a long time (months) without deterioration. It is certain that revealing the mechanism by which this occurs will inspire the preservation of blood for a long time in blood transfusion.