Epidemiology of Toxocara spp. in stray dogs and cats in Dublin, Ireland.

A survey was undertaken to study the epidemiology of Toxocara spp. in 350 dogs and 181 cats. A prevalence of 82.6% was recorded for Toxocara canis and 42% for T. cati. The distribution of parasite burdens in both dogs and cats was overdispersed. The highest parasite prevalence rates and burdens were found in hosts of 12 to 24 weeks of age. No Toxocara parasites were found in cats between 0 to 4 weeks old. There was no significant difference in parasite prevalence between male and female dogs or between male and female cats. The relationships between host age and sex with parasite prevalence, burden and length are discussed. Female T. canis worms with mature ova and those with immature ova differed significantly with regard to their length. The relationship between the length of mature T. canis female worms and the proportion of body length occupied by the uterus was highly significant.