Efficacy of toltrazuril in the prevention and the treatment of suckling piglets coccidiosis :: results of two field trials

Two field trials were conducted to evaluate the efficacy of toltrazuril (5 % solution) to control intestinal coccidiosis due to Isospora suis on piglets. The purpose of the first trial was to determine the optimal posology. Forty litters were divided into 4 batches: three batches treated at D7 (with 10, 20 or 30 mg/kg of body weight) and one negative control group. All the piglets of a sow were allotted to the same batch. Ooocyst excretion and the rate of diarrhoea were evaluated on faeces samples taken every two days between D7 and D20. Each piglet was weighted every week. The purpose of the second trial was to confirm the posology found during the trial 1. Twenty-one litters (20 mg of toltrazuril per kg of body weight), treated between D3 and D5, were compared to 20 other litters taken as controls. This second trial lasted one week more and the diarrhoea intensity was evaluated. The other criteria were the same as for trial 1. Optimal posology is 20 mg/kg of body weight. With this posology, until weaning, oocyst excretion was stopped, the diarrhoea frequency was significantly reduced. The growth was higher at least until two weeks of age. For the two other treatments (10 and 30 mg at D7) oocyst excretion was stopped but the growth was lower than in the 20 mg group.