Water soluble preparations of coccidiostats

Active substance preparations characterised by a) up to 10000 ppm, based on the weight of the preparation, of one or more coccidiostats of the general formulae I and II in which R , R and R' are, independently of one another, hydrogen or C1-C4-alkyl, R is together with R a double bond or independently thereof hydrogen or C1-C4-alkyl, R is together with R a double bond or independently thereof hydrogen or C1-C4-alkyl, W is oxygen or sulphur, X is, in each case independently of one another, halogen such as fluorine, chlorine and bromine, C1-C4-alkyl, trifluoromethyl, cyano, thiocyanato, C1-C4-alkylthio, nitro or C1-C4-alkoxy, n is 0, 1, 2, 3 or 4, preferably 0 to 2, Y is hydrogen, C1-C6-alkyl, C1-C6-halogenoalkyl, benzyl, phenyl or phenyl which is substituted by at least one radical from the group comprising alkyl, alkoxy, halogenoalkyl, halogenoalkoxy, halogen, alkylthio, alkylsulphinyl, alkylsulphonyl, halogenoalkylthio, halogenoalkylsulphinyl and halogenoalkylsulphonyl, each with 1 to 4 C atoms in the alkyl radical, or is thienyl or halothienyl and Z is a direct bond or a divalent group of the formula O, S, SO, SO2, NH, NR in which R is hydrogen or C1-C4-alkyl, or C(CN)(R) in which R is hydrogen or methyl, b) a water-miscible, physiologically acceptable, anionic or non-ionic surfactant or a mixture of a plurality of these surfactants and c) 0 to 80% by weight, based on the preparation, of a physiologically acceptable, water-soluble organic solvent and d) 0 to 70% by weight, based on the preparation, of water, are suitable, by reason of their solubility in water, for the treatment of coccidiosis in livestock via the drinking water thereof.