Studies on short-term application of drugs to Eimeria tenella in tissue culture.

The anticoccidial action of 6 drugs was studied by treating cell cultures with drug for 24 h after inoculation of the cultures with sporozoites of Eimeria tenella. A monitoring technique was used to confirm that the drug was being removed. Only monensin was shown to be coccidiocidal. Amprolium, lasalocid, methyl benzoquate, nicarbazin and robenidine were coccidiostatic at their minimum effective doses. Misleading coccidiocidal effects were observed when higher concentrations of methyl benzoquate, nicarbazin or robenidene were used.