An animal is provided with an effective amount of 4-tert-butylphenethylquinazolin-4-yl ether or 4-chloro-5-ethyl--carboxamide or 5-chloro-N-[2-[4-(2-ethoxyethyl)-2,3-dimethylphenoxy] ethyl] A method for controlling an ex vivo parasite that infects companion animals and livestock animals by applying 3-ethyl-1-methyl-N-[4-(p-tolyloxy) benzyl] pyrazole-5-carboxamide is described.동물에게 유효량의 4-3급-부틸페네틸 퀴나졸린-4-일 에테르 또는 4-클로로-5-에틸-2-메틸-N-[(4-3급-부틸페닐)메틸]피라졸-3-카복스아미드 또는 5-클로로-N-[2-[4-(2-에톡시에틸)-2,3-디메틸페녹시]에틸]-6-에틸-4-피리미딘아민 또는 4-클로로-3-에틸-1-메틸-N-[4-(p-톨릴옥시)벤질]피라졸-5-카복스아미드를 적용함으로써 반려 동물 및 가축 동물을 감염시키는 체외기생충을 방제하는 방법이 기재된다.
