You are not a dr. You are not a scientist. Sorry, but it is true, if you are, I apologize, lol.
Even then, health care professionals are advised not to treat their own (pets, family, friends) as they can not be objective.
The best person to advise you regarding heartworm/flea/tick preventives is a veterinarian that you have a good relationship with and that has examined your dog, knows the area you live in and the level of risk involved.
Blanket statements do not work. You can look up medical articles all day long……the information is not specific to your dog.
Find a vet that you trust and listen to him. Good luck
Ps: Once the lab values are off, it is often too late, the damage is done.
