Application of a new therapeutic protocol against Neospora caninum-induced abortion in cattle: a field study.

A field evaluation of a new therapeutic protocol based on Toltrazuril and/or Sulphadiazine and Trimethoprim was carried out for treatment of Neospora caninum-induced abortion in dairy cattle. 936 randomly chosen Friesian bovine belonging to 18 dairy herds of Central and South Italy with history of high number of abortions per year were considered. Since the high N. caninum seroprevalence, Sulphadiazine 200 mg/ml and Trimethoprim 40 mg/ml was given to the cattle at a dosage of 20 mg/kg bw, following different age-depending protocols. Toltrazuril 50 mg/ml was also given at 20 mg/kg bw to newborn cattle and once every three months for one year to the dogs present in the farm; a periodic treatment of environment was carried out with a phenolic disinfectant. The concomitant treatment of all the animals present in the herd, dogs included, with a Toltrazuril and/or Sulphadiazine and Trimethoprim based protocol was efficacious for treatment of N. caninum infection in dairy cows. The efficacy of this protocol was demonstrated by drastic reduction of abortion (from 188 to 9) and of N. caninum seroprevalence (from 68.7% to 0%) after one year of treatment.