Indirect solid-phase microradioimmunoassay for detection of Ascaris suum antibodies in swine sera.

Antibodies to Ascaris suum have been detected and quantitated in sera of swine orally inoculated with eggs of A suum, using an indirect solid-phase microradioimmunoassay. Antibody titer of 1:640 to 1:10,240 were quantitated, using purified and crude ascarid antigens in the assays. Swine sera from 71 of 72 farm herds located in 37 counties in Nebraska had at least 1 serum of the 7 tested with a titer equal to or greater than 1:20. A total of 437 sera were positive and 67 negative (ie, less than 1:20 titer). Six positive sera selected at random had titers of 1:640 to 1:5,120.