The present invention relates to novel anthelmintic compounds of formula (I) below: wherein Y and Z are independently a bicyclic carbocyclic or a bicyclic heterocyclic group, or one of Y or Z is a bicyclic carbocyclic or a bicyclic heterocyclic group and the other of Y or Z is alkyl, alkenyl, alkynyl, cycloalkyl, phenyl, heterocyclyl or heteroaryl, and variables X1, X6, X8, Q1, Q2, Q3, Q4, Q5, Q6, Ring A, Ring B, W, W′, R2, R3, R, R′, m, n and q are as defined herein. The invention also provides for veterinary compositions comprising the anthelmintic compounds of the invention, and their uses for the treatment and prevention of parasitic infections in animals.