Pathological Observations of the Intestinal Lesions Induced by Caryophyllid Cestodes in Clarias batrachus (Linnaeus) (Siluriformes : Clariidae)

Abstract

The comparative histopathology as related to modes of attachment and scolex morphology, gross anatomy, host response and effects of the three caryophyllid cestodes Djombangia penetrans, Lytocestus indicus and L. parvulus was studied. Among them D. penetrans was found to be most pathogenic and elicited pronounced host reaction in the form of nodules and complete penetration of the intestine followed by L. indicus which caused shallow ulcers and mechanical obstruction, and L. parvulus caused denudation of the host intestinal tissues. Distribution of the cestodes in the intestine, multiple infections and niche widths as related to scolex morphology, modes of attachment as well as habitats are discussed. Photomicrographs of the species in situ, and of histopathology supplement the observations.