An evaluation of seroreactivity of antigenic preparations of Fasciola gigantica in goats

Seroreactivity of Fasciola gigantica, somatic (SAg), excretory-secretory (E SAg) and egg (EAg) antigens, was evaluated using immunodiffusion tests (DID and CIEP) and enzyme-linked immunosorbent assay (ELISA). The referral anti gens were evaluated against 50 Fasciola-free vis-a-vis 50 Fasciola-positive serum samples collected from goats slaughtered at local abattoir. The goat s positive for infection, had low fluke recovery of 27+/-12. The immunodiff usion tests (DID and CIEP) had higher specificity (98 and 96%) than ELISA ( 92%), in detecting the fasciolosis-positive goats. Amongst the 3 tests used , ELISA with SAg had the highest sensitivity (96%), whereas with EAg, the l owest (82%) and ESAg occupied position closer to SAg. In CIEP, the egg anti gen performed better in detecting low grade infection of caprine fasciolosi s than SAg or ESAg. The formation of perception lines in proximity of EAg c ontaining wells (cathodic end) in CIEP, was suggestive of high molecular we ight of Fasciola gigantica specific moieties in egg antigen. Purification, isolation and characterization of such protein molecules from the referral antigens has been suggested for further qualitative improvement.