Disclosed are ivermectin derivative compounds of formula (II), wherein the substituents are as described within the specification. Also disclosed is a composition comprising an N-phenylpyrazole compound of formula (I) and an ivermectin derivative compound of formula (II), wherein the substituents are as described within the specification. Further described is a method for the treatment of prophylaxis of a parasitic infection or infestation in a bird or non-human mammal which comprises administering a pharmaceutically effective amount of said composition, wherein the composition is in the form selected from the group consisting of a ready-to-use formulation, pour-on formulation, a spot-on formulation, paste formulation, oral drench formulation, transdermal or transmucosal formulation, chewable formulation and injectable formulation.
