My Husky is on antibiotics for the treatment of heart worms, but has lost his taste for his food, any suggestions?

It's OK to give him his favorite people food (within reason) with the pill pressed into it, when he's that sick and won't touch his dog food. A tiny piece of cheese, or meat?
It's OK to put a little of his favorite food on top of his kibble too. Cooked egg, hamburger, chicken, whatever he wants.

If that fails, here is an instructional video on giving a dog a pill:

How To Give Your Dog a Pill - YouTube

Some antibiotics will cause a dogs stomach to get upset. They will go off feed temporarily while taking these types of antibiotics.

You need to contact your vet and tell them your dog is not eating. They need to adjust your dosage or give a different antibiotic. A lot of medicines need to be given with food.

A spoon full of peanut butter or hidden in some cheese always work for me with pills.
Yes, I believe it's okay to add a little chicken hamburger or egg to his kibble if that gets him to eat. However, I would make sure there is no seasoning, onions, etc in the meat. Also, be careful not to overfeed him. He may be suffering with an upset stomach.

Since you are saying that the antibiotic is given for heartworms, I am going to assume that Doxycycline is the antibiotic that you are using.
The GI side effects are often lessened when given after a meal. (usually)
Vibramycin
Here is a little info on the drug.
If you are having to pill him it is best to follow the pill with a syringe full of water as it can cause irritation to the esophagus if it gets hung in there.
Above all, call your vet with your concerns about decreased appetite, it may very well be linked to the antibiotic.
And peanut butter works great at my house.