Pathological manifestations of the acanthocephalan parasite, Tenuiproboscis sp. in the mangrove red snapper (Lutjanus argentimaculatus) (Forsskål, 1775), a candidate species for aquaculture from Southern India

The study describes the pathological manifestations of the acanthocephalan, Tenuiproboscis sp. in the mangrove red snapper, Lutjanus argentimaculatus, a highly valued food fish along the southwest coast of India. The fish collected from Calicut, Cochin and Kannur harboured the acanthocephalan parasite, Tenuiproboscis sp. with up to 100% prevalence. Heavy infections with the parasites were observed in the posterior region of the intestine, almost blocking the lumen. At the site of parasite attachment, the surface of the intestine appeared thickened and the mucosal epithelium showed compression and abrasion. Intestinal folds were eroded along with thickening of lamina propria. The presoma of the parasites pierced the mucosal epithelium, lamina propria, muscle layers and serosa, reaching the peritoneal cavity, surrounded by a tunnel with collagenous fibers and granulocytes. Inflammation, granular tissue formation, connective tissue proliferation and associated host immune reactions were evident. Though the worms substantially damaged the architecture of the intestinal tissues, no apparent ill effects on the general health/condition of the fish were observed. The parasite was also recovered from Epinephelus malabaricus and Lates calcarifer. This is the first report of Tenuiproboscis sp. from L. argentimaculatus, E. malabaricus and L. calcarifer.