REGENERATION IN EUDRILUS EUGENIAE KINBERG 1867 (OLIGOCHAETA, ANNELIDA)

Abstract

Earthworm EudriluseugeniaeKinberg 1867, commonly known as African night crawler is an efficient organic waste decomposer. As the dedifferentiation patterns of these invertebrates are like vertebrates, they are excellent candidates for regeneration studies. We made 12 amputations along the earthworm to demarcate anterior and posterior sections for regeneration studies. Regeneration events included wound healing, blastema formation, segmentation, pigmentation and functional clitellum formation. Clitellum formation was noted in the posterior segments after 28-30 days of amputation, whereas anterior segments without clitellum did not survive after 30days. In both anterior and posterior segments, number of segments remaining after amputation proved to be a significant factor in determining the survival rate. Earthworms with less than one fourth of the body length showed very low survival rates.But no significant correlation existed between the lengths of regenerating fragment and number of remaining segments in the amputated worms. Analysis of variance showed no significant difference between regeneration rates of different segments in anterior segments whereas the posterior segments showed significant difference in the regeneration rates.