Method for Combatting Fish Mycoses and One-Celled Ectoparasites

1. A method for controlling fish mycoses and single-cell ectoparasites of fish, which comprises applying to fish or their habitat an effective amount of compound suitable for inhibiting the mitochondrial respiratory chain at the stage of the b/c.sub.1 of the formula IA or IB ##STR3## is used where . . . is a single or double bond and the index and the substituents have the following meanings: R' is --C[CO.sub.2 CH.sub.3 ].dbd.CHOCH.sub.3, --C[CO.sub.2 CH.sub.3 ].dbd.NOCH.sub.3, --C[CONHCH.sub.3 ].dbd.--NOCH.sub.3, --C[CO.sub.2 CH.sub.3 ].dbd.CHCH.sub.3, --C[CO.sub.2 CH.sub.3 ].dbd.CHCH.sub.2 CH.sub.3, --C[COCH.sub.3 ].dbd.NOCH.sub.3, --C[COCH.sub.2 CH.sub.3 ].dbd.NOCH.sub.3, --N(OCH.sub.3)--CO.sub.2 CH.sub.3, --N(CH.sub.3)--CO.sub.2 CH.sub.3, --N(CH.sub.2 CH.sub.3)--CO.sub.2 CH.sub.3, R" is a C-organic radical, a C-organic radical which is bonded directly or via an oxy, mercapto, amino or alkylamino group, or together with a group X and the ring Q or T, to which they are bonded, are an unsubst. or subst. bicyclic, partially or completely unsaturated system which, in addition to carbon ring members, can contain heteroatoms from the group consisting of oxygen, sulfur and nitrogen, R.sup.x is --OC[CO.sub.2 CH.sub.3 ].dbd.CHOCH.sub.3, --OC[CO.sub.2 CH.sub.3 ].dbd.CHCH.sub.3, --OC[CO.sub.2 CH.sub.3 ].dbd.CHCH.sub.2 CH.sub.3, --SC[CO.sub.2 CH.sub.3 ].dbd.CHOCH.sub.3, --SC[CO.sub.2 CH.sub.3 ].dbd.CHCH.sub.3, --SC[CO.sub.2 CH.sub.3 ].dbd.CHCH.sub.2 CH.sub.3, --N(CH.sub.3)C[CO.sub.2 CH.sub.3 ].dbd.CHOCH.sub.3, --N(CH.sub.3)C[CO.sub.2 CH.sub.3 ].dbd.NOCH.sub.3, --CH.sub.2 C[CO.sub.2 CH.sub.3 ].dbd.CHOCH.sub.3, --CH.sub.2 C[CO.sub.2 CH.sub.3 ].dbd.NOCH.sub.3, --CH.sub.2 C[CONHCH.sub.3 ].dbd.NOCH.sub.3, R.sup.y is oxygen, sulfur, .dbd.CH-- or .dbd.N--, n is 0, 1, 2 or 3, where the radicals X can be different if n>1; X is cyano, nitro, halogen, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -haloalkyl, C.sub.1 -C.sub.4 -alkoxy, C.sub.1 -C.sub.4 -haloalkoxy, C.sub.1 -C.sub.4 -alkylthio or, in the case where n>1, a C.sub.3 -C.sub.5 -alkylene, C.sub.3 -C.sub.5 -alkenylene, oxy-C.sub.2 -C.sub.4 -alkylene, oxy-C.sub.1 -C.sub.3 -alkylanoxy, oxy-C.sub.2 -C.sub.4 -alkenylene, oxy-C.sub.2 -C.sub.4 -alkenylenoxy or butadienediyl group bonded to two adjacent C atoms of the phenyl ring, where these chains in turn can carry one to three of the following radicals: halogen, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -haloalkyl, C.sub.1 -C.sub.4 -alkoxy, C.sub.1 -C.sub.4 -haloalkoxy or C.sub.1 -C.sub.4 -alkylthio, Y is .dbd.C-- or --N--, Q is phenyl, pyrrolyl, thienyl, furyl, pyrazolyl, imidazolyl, oxazolyl, isoxazolyl, thiazolyl, thiadiazolyl, triazolyl, pyridinyl, 2-pyridonyl, pyrimidinyl or tridzinyl, T is phenyl, oxazolyl, thiazolyl, thiadiazolyl, oxadiazolyl, pyridinyl, pyrimidinyl or triazinyl.

2. A method for controlling fish mycoses and single-cell ectoparasites of fish, which comprises applying to fish or their habitat an effective amount of a compound suitable for inhibiting the mitochondrial respiratory chain at the stage of the b/c.sub.1 of the formula IC ##STR4## is used where the index and the substituents have the following meanings: x is cyano, nitro, halogen, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -haloalkyl, C.sub.1 -C.sub.4 -alkoxy, C.sub.1 -C.sub.4 -haloalkoxy or C.sub.1 -C.sub.4 -alkylthio; n is 0, 1, 2 or 3, where the radicals x can be different if the value of n is greater than 1; R' is C[CO.sub.2 CH.sub.3 ].dbd.CHOCH.sub.3, C[CO.sub.2 CH.sub.3 ].dbd.NOCH.sub.3, C[CONHCH.sub.3 ].dbd.NOCH.sub.3, C[COCH.sub.2 CH.sub.3 ].dbd.NOCH.sub.3 or N(OCH.sub.3)--CO.sub.2 CH.sub.3 ; R is phenyl, pyrazolyl, pyridyl or pyrimidyl, where these groups can be partially or completely halogenated and/or can carry one to three of the following radicals: cyano, nitro, C.sub.1 -C.sub.4 -alkyl, C.sub.3 -C.sub.6 -cycloalkyl, C.sub.1 -C.sub.4 -haloalkyl, C.sub.1 -C.sub.4 -alkoxy, C.sub.1 -C.sub.4 -haloalkoxy and C.sub.1 -C.sub.6 -alkylthio and/or a CR.sup.1 .dbd.NOR.sup.2 group or a phenyl ring which in turn can be partially or completely halogenated and/or can carry one to three of the following radicals: cyano, nitro, C.sub.1 -C.sub.4 -alkyl, C.sub.3 -C.sub.6 -cycloalkyl, C.sub.1 -C.sub.4 -haloalkyl, C.sub.1 -C.sub.4 -alkoxy, C.sub.1 -C.sub.4 -haloalkoxy and C.sub.1 -C.sub.6 -alkylthio; N.dbd.CR.sup..alpha. R.sup..beta. or N.dbd.CR.sup..gamma. CR.sup..delta. .dbd.NOR.sup..epsilon. ; R.sup.1, R.sup.2, R.sup..alpha., R.sup..gamma. and R.sup..epsilon. are C.sub.1 -C.sub.4 -alkyl, R.sup..beta. is phenyl, pyridyl or pyrimidyl, where these groups can be partially or completely halogenated and/or can carry one to three of the following radicals: cyano, nitro, C.sub.1 -C.sub.4 -alkyl, C.sub.3 -C.sub.6 -cycloalkyl, C.sub.1 -C.sub.4 -haloalkyl, C.sub.1 -C.sub.4 -alkoxy, C.sub.1 -C.sub.4 -haloalkoxy and C.sub.1 -C.sub.6 -alkylthio; R.sup..delta. is C.sub.1 -C.sub.4 -alkyl or phenyl, which can be partially or completely halogenated and/or can carry one to three of the following radicals: cyano, nitro, C.sub.1 -C.sub.4 -alkyl, C.sub.3 -C.sub.6 -cycloalkyl, C.sub.1 -C.sub.4 -haloalkyl, C.sub.1 -C.sub.4 -alkoxy, C.sub.1 -C.sub.4 -haloalkoxy and C.sub.1 -C.sub.6 -alkylthio and/or a CR.sup.1 .dbd.NOR.sup.2 group.