Experience in northern Nigeria with countercurrent immunoelectrophoresis, double diffusion and indirect haemagglutination tests for diagnosis of hydatid cyst in camels

Sera from 36 slaughtered camels with proven hydatid disease, from 46 camels found to be free of hydatidosis at post-mortem meat inspection, and from 26 animals with confirmed caprine heartwater, bovine trypanosomiasis and cysticercosis were examined. The indirect haemagglutination was found to be the most sensitive but least specific of the three tests. Ouchterlony's double diffusion (DD) test was specific and fairly sensitive. Although the countercurrent immunoelectrophoresis was as specific as DD, it was the least sensitive of the three serological tests. All three serological tests were always positive in camels with hydatid cyst infection affecting both the liver and the lung. A combination of indirect haemagglutination and Ouchterlony's double diffusion test could be useful for diagnosing hydatidosis in camels and probably other animals.