Here's a suggestion- get yourself some good colloidal silver (or for economy buy yourself a home silver maker such as the inexpensive Silver Bullet from CZ sponsor Utopia Silver - and use the CZ discount code of LR001 to get 15% off if it isn't currently on sale). Add a bit to their water bowls every so often and they should enjoy good health and renewed vigor. Time and again people have told me how their older dogs had energy and playfulness they had not seen in years after giving them regular colloidal silver. It also helps restore/prevent back and hip problems often seen when dogs get older. We have a ten year old found dog who gets regular silver in her water and she still frolics like a puppy. I am not sure what it might do against parasites, but it absolutely will protect against parvo. And, as I mentioned before, it has a good history of helping get rid of fatty tumors in dogs.