Serologic differentiation of larval Toxocara and Ascaris.

Antigenic extracts of adult and larval T. canis and A. suum have been used in microgel double diffusion technique to differentiate antibodies produced in animals, experimentally infected with these parasites. Antigenic extracts from adult Ascaris reacted with the sera from animals infected with A. suum but the extracts from adult Toxocara failed to react or reacted feebly with the sera from animals infected with T. canis. Interestingly the antigenic extract from adult Toxocara reacted with the sera from animals infected with Ascaris. The antigens extracted from embryonated eggs of both the worms reacted with anti-Toxocara larval serum but could not absorb all the specific antibodies in the interagel absorption test.