Thanks Livinthdream, I should have mentioned that we used that and another product that is green jelly things, but if anything it encouraged the beagle. The spaniel didn't like it, but it didn't make a difference to the beagle. The fence extensions were actually the last straw after trying numerous other options.

I guess my question is how old should I expect them to be before they grow out of things like this, or will they always do it?