My name is ***** ***** I am an experienced small animal veterinary surgeon, I will be very pleased to work with you today and will try my best to answer your question to your satisfaction.
Actually if this class of product goes on to the fur as opposed to the skin then it is not likely to be so effective
It will have worked to some degree though so my usual advice is to wait two weeks and then apply it again and then reset to the regular intervals from then on. That should be fine ...
I hope I have covered your question fully enough but if you would like further clarification or to talk things over a bit more then I will be on-line for the next hour or so and I will be more than pleased to continue working with you.Regards,Scott