re: Dog flea and heartworm meds

If you don't have a collie, you can use Ivermectin for heartworms, which is dirt cheap. Ivermectin is the ingredient in Heartguard, and if you dose it yourself using the Ivermectin for sheep (cheap at a feed store), you'll save a ton of money.

My sister has around 60 foxhounds and she spends less for heartworm control than I do with a Border Collie and an Aussie.

Collies can be ivermectin sensitive.

Here's a link that explains it all:

Ivermectin on the Cheap