Once applied to a cat toy, how long does it last before it needs re-applying?
Initially the effect will last anywhere from 5 minutes to half an hour, after which point the Purr stops having an effect on the cat even if you give them some more Purr on a fresh toy. After about an hour (maybe more, maybe less) they will show interest in new Purr on a fresh toy. They may also show some interest in the original toy without adding any Purr, although probably not as much as they might with a fresh application of Purr. We have done some experiments and it seems that even several weeks later a toy that previously had Purr on it will generate more interest than an un-Purred toy. The extent of the interest varies from cat to cat and seems to be affected by other unknown factors – sometimes, it seems, a cat just doesn’t want to play. On the whole a fresh application of Purr gives the best effect but some residual effect can be noticed for quite some time afterwards.
