Substituted pyrimidinium compounds of the general formula (I) and their uses for combating animal pests The present invention relates to substituted pyrimidinium compounds of formula (I), to the stereoisomers, salts, tautomers and N-oxides thereof and to compositions comprising such compounds. The invention also relates to methods and uses of these substituted pyrimidinium compounds and of compositions thereof, for combating and controlling animal pests. Furthermore the invention relates also to pesticidal methods of applying such substituted pyrimidinium compounds. The substituted pyrimidinium compounds of the present invention are defined by the following general formula (I): wherein X, Y, Z, R