Toxocara vitulorum is a nematode parasite of small intestine of buffaloes, particularly young age calves, causing economic and public health problems. Evaluation of the immunogenicity and diagnostic sensitivity of three selected T. vitulorum antigens include excretory secretary antigens (ESAg) , Pre-enteric Ag (PeAg) and embryonated egg Ag (EEAg) were evaluated on the experimental and field level. PeAg appears as the most sensitive antigen in specific detection of anti-T.vitulorum antibodies (ATVAb). In inspected sera using ELISA Fractionation of the three T. vitulorum antigens using SDS-PAGE and determination of the specific fractions using EITB versus rabbit-hyper-immune sera (RHIS) and natural infected buffaloes and calve sera revealed that the bands corresponding to M.W of 105, 90, 67, 19 & 11 kDa reacted specifically. Marked specific reaction even with sera from animals infected by low eggs/gram was recorded versus the fraction of 67 kDa in the fractionated PeAg. This work identified this protein fraction as the most specific and sensitive one can be used for routine diagnosis on the field level.