Gasterointestinal cooperiasis: A mini review on an incidence of unusual malady of Cooperia pectinata (Ransom, 1907) in a calf from Tamil Nadu

A review on cooperiasis in cattle caused by Cooperia pectinata was described based on the authentic episode of the malady in a calf. A four-month-old Jersey cross-bred calf was presented for necropsy with the clinical history of inappetence, anaemia, diarrhea, weakness and death. Systematic post-mortem examination was conducted. Externally, carcass was thin with blanched mucous membranes. Internally, edematous fluid accumulated in pericardial sac, thoracic and abdominal cavities. Proximal small intestine revealed scattered nodules. Lumen of the distal abomasum and duodenum contained pale viscous contents and numerous pale yellowish-brown, hairy nematodes. Histologically, small intestine revealed acute catarrhal enteritis. Mucosal villi were blunt, fused and showed scattered areas of epithelial necrosis. Muco-serosal nodules revealed necrotic cell debris, throngs of neutrophils, eosinophils and few macrophages encircling the dead and degenerating nematodes. Nodules were thought to be hypobiosis of parasitic larval (L4&L5) stages. Muco-serosal nodules upholds the penetrating nature of the parasite and explained the host cell-mediated immune response. Morphologically, the parasites were identified as Cooperia pectinata. Adult male was identified with its morphology of spicules, structure and arrangement of bursal rays. Adult female was identified with its morphology of vagina and ovijector. The penetrating nature of the C. pectinata was responsible of intestinal pathology which in turn caused acute malady characterized by anaemia, diarrhea, loss of body weight gain, emaciation and death. The paper elaborates the pathology and pathogenesis of C. pectinata in cattle and records the incidence in southern India at-long-last documented evidence after 1940 from Madras state.