antigenic cross-reactivity among haemonchus contortus, oesophagostomum columbianum and trichuris ovis of goat

background: cross antigenicity is the major problem in developing a reliable tool for immunodiagnosis and immunoprophylaxis of parasitic diseases. mixed infection due to different types of gastrointestinal parasites is more common than single species infection under field condition. methods: the present study was undertaken to detect antigenic cross-reactivity among haemonchus contortus, oesophagostomum columbianum and trichuris ovis of goats by sds-page and western blot analysis using hyperimmune sera (his) rose in rabbit separately against the antigens of the three nematode species. results: thirteen, 16 and 14 polypeptides in crude somatic antigen (csag) of h. contortus (csag-hc), o. columbianum (csag-oc) and t. ovis (csag-to), respectively, were resolved in sds page analyses. it was revealed that 54 kda peptide was shared by h.contortus and o. columbianum , whereas 47 kda peptide was shared by o. columbianum and t. ovis . western blot analyses revealed that three immunogenic polypeptides (mw 54, 49 and 42 kda) in csag-hc, five in csag-oc (54, 47, 44, 38 and 35.5 kda) and csag-to and five polypeptides (90, 51, 47, 39.5 and 31 kda) in csag-to cross-reacted with the heterologous his. four species-specific immunoreactive polypeptides (92, 85, 65 and 39 kda) of h. contortus and two (72 & 26 kda) in o. columbianum were also identified in the study.  conclusion: the shared polypeptides and species-specific polypeptides might be evaluated as protective antigen and subsequently exploitation for developing immunodiagnostic and for immunoprophylactic tools of for these common nematode species.