Toxocara vitulorum in beef calves in North Central Florida

In this study, we evaluated the prevalence of Toxocara vitulorum in beef calves in North Central Florida. Fecal samples from 433 calves under 9 months of age were analyzed for the presence of eggs in their feces. The prevalence in calves less than 3 months of age was 17.6%, 3–4 months of age was 0.4% and those 5–6 months old had a 0.9% prevalence. As expected, no eggs were detected in any calves older than 6 months. Calves were treated with fenbendazole (10% FBZ) at 5 mg/kg after fecal samples were collected. Twenty calves that had T. vitulorum eggs in the feces were resampled 2 weeks after treatment to evaluate effectiveness of FBZ. No T. vitulorum eggs were seen in the feces of 17/20 (85%) of the calves that were sampled after FBZ treatment. FBZ was effective in 85% of calves treated for T. vitulorum infection in calves. We would like to make beef ranchers and veterinarians in the southern states aware that the prevalence of this parasite has greatly increased recently in northern Florida beef units.