Identification of antigenic similarities in oviductal proteins among cattle, buffalo and goat. Buffalo oviductal proteins were isolated and hyper immune sera was raised in rabbits against buffalo oviductal proteins. Double immuno diffusion (DID) was used to detect homologous protein in the oviductal secretions of cow, buffalo and goat. For detection of immunologically homologous proteins in oviductal proteins enzyme linked immuno electro transfer blot was done. Results of DID indicated identical oviductal proteins among cow, buffalo and goat. At least one oviductal protein (molecular weight of 60 kDa) was similar among cow, buffalo and goat. A 70 kDa protein was observed in goat oviductal proteins, which was absent in cattle and buffalo oviductal fluid. It was inferred that cattle, buffalo and goat share homologous oviductal proteins, indicating the possibility of using oviductal proteins from buffalo to modulate the functions of cattle and goat spermatozoa. However, the functional analysis of the homologus proteins needs to be elucidated.