IMMUNOLOGICAL STUDY OF Toxocara canis IN DOGS AND MICE AT BASRAH CITY

Abstract

Sixty-five sera samples were collected from stray dogs in Basrah which included 31 dogs infected with T. canis, 21 dogs infected with cestodes, while 13 dogs were infected with other nematodes then T. canis. The antibody concentration for eggs crude antigen (ECA) and adult crude antigen (ACA), adult purified antigen (APA) was evaluated using IHAT test for monitoring toxocariasis in dogs. The sensitivity of the above antigens was 64.5, 86.2 and 93.5%, respectively, while the specificity was 84.4, 93.8 and 100 %, respectively.Furthermore, the predictive values were 80.0, 92.6 and 100 %, respectively, while, the likelihood ratio was 4.5, 14.3 and ∞ for the above antigens. No cross reaction was detected between the above three antigens and the infection with cestodes. A total of 48 sera samples from mice experimentally infected with 2nd stage larvae of T. canis with two doses (250 and 500 larvae) at 1, 2, 3 weeks and 2, 4, 6 days post - infection. IHAT was used with larval excretory/ secretory and tegumental larval antigens. The total sensitivity was 91.66% and 83.33% for E/S, while it was 58.33 and 50% for TES, respectively. The specificity was 100% for E/S and TES at both doses, respectively. The predictive value for E/S was 91.66% in dose (500) larvae and 95.83% at second dose (250, larvae). It was found that in case of TES antigen, the predictive value was 75% and 79.16% at both doses (500 and 250 larvae, respectively). There was no cross-reaction between the above larval antigens and the infection with cestodes and nematodes