Examination of the intestinal tract of Clarias gariepinus showed that Procamallanus laeviconchus infects both the stomach and hind gut of the intestine. In the stomach of the infected fish, the parasite penetrated to the submucosal layer. The presence of the parasite was found to be accompanied by goblet cell hyperplasia, cellular infiltration, degeneration of connective tissue, and formation of compact fibrous capsule around the cephalic end of the parasite. In the intestine, the nematode parasite was found to penetrate through the mucosal and submucosal layers. In the mucosal layer, the parasite caused complete elimination of the epithelial cells at the point of attachment and degeneration of host tissue, accompanied by blood cell leakage into the lumen of the intestine. In the submucosal layer, the loose connective tissue was completely eroded.
Procamallanus laeviconchus, Clarias gariepinus, Nematoda, histopathology