try added some mollasses into the feed as it is a strong taste it normally disguises it as my horse wouldnt eat it even in an apple!

i had the same problem with my horse, i tried putting it in feed but he could tell, soi left it over night then tried again and he had it all.

does it takes a bit. if so have a look at this weblink.

http://www.easywormer.com/about.html