Diagnostic potential of 36-55 kDa somatic antigens of Fasciola gigantica for bovine fasciolosis

Abstract

Fascioliasis causes huge economic losses in livestock industry by reducing the growth, fertility rate, meat and milk yield. In the present study, somatic antigens isolated from Fasciola gigantica were assessed for the early detection of infection by developing antibody detection enzyme immunoassay. The somatic antigens extracted from adult F. gigantica worms was separated on SDS-PAGE and immunogenicity was determined by Western blot (WB). The results showed polypeptides bands between 15 to 95 kDa, and most prominent bands were 15, 28, 36, 38, 55, 72 and 95 kDa polypeptides. The WB revealed a single polypeptide of size between 36 to 55 kDa as antigenic. The sensitivity and specificity of ELISA test established for 36 to 55 kDa somatic antigens was 95.45% (95% CI: 77.16% to 99.88%) and 87.1% (95% CI: 70.17% to 96.37%), respectively. Kappa value revealed that the strength of agreement is considered to be very ‘good’. In house established ELISA was implemented in the field and 12.1% (31/256) large ruminants were found positive, while 4.68% (12/256) with postmortem examination. The fasciolosis did not show significant (P>0.05) association with host type, breed and age groups, while significant (P<0.01) association with host sexes. The result confirmed that in-house established ELISA test had good value for serodiagnosis of fasciolosis in cattle and buffaloes for large scale epidemiological studies.