I went on the U of G website looking up the Ontario Veterinary College, to see if I can get a cardiologist to check out my pups supposed heart murmur, and found this intersting stats on HW in Canada. Very interesting, cuz I've had numerous conversations with several pet owners about the "should you" have your dogs on HW meds. I think you should and I think these stats (a few years old, and not complete), should prove for some concern in owners who don't think they need their dogs on HW, just cuz their vet says they don't have to. (Vets need to make a living somehow). Brantford alone had 26, and thats just minutes away from me.
http://www.ovc.uoguelph.ca/PathoBio/...HEARTWORM.html