An immunofluorescence technique for the detection of Toxocara canis antibodies

Abstract

An immunofluorescent (IF) test for the serodiagnosis of Toxocara canis infections in puppies is described. Frozen sections of male adult T. canis worms were used as antigen. A group of seven puppies, 6 weeks of age, was infected orally with 10 000 embryonated T. canis eggs each. In the sera of all animals IF antibodies could be detected from approximately 4 weeks after infection onwards. Titers were detectable until the end of the observation period (22 weeks). Two puppies of the same age were infected with 30 000 or 50 000 embryonated T. canis eggs respectively. Positive IF results were also obtained in the sera of these pups from week 4 post infection (p.i.) onwards. No correlation between titer and initial number of egges administered was observed. Furthermore, no correlation was noticed between titer and number of adult worms recovered from the dogs. For comparison all sera were tested with the complement fixation (CF) test, using cuticle material of adult worms as antigen. Complement fixing antibodies could be detected in none of the serum samples.