Updated on March 25, 2014
What is Heartworm and Why is My Dog Tested?
Heartworm is a large internal parasite that is spread through the mosquito. Dogs with a case of heartworm disease start out with mild symptoms like coughing and exercise intolerance but later develop full blown cardiomyopathy (with swelling in the limbs, fluid buildup in the lungs, and reluctance to move as the dog becomes quickly exhausted).
Testing dogs from the shelter, older dogs that have never been on preventative, and dogs that have been off of preventative for a long time is really needed. Annual testing of dogs that are on heartworm preventative is not necessary, however. It is not harmful to the dog, only to your wallet, so unless you feel the need to test you should just keep your dog on the preventative. . . . . . . . . . .more. . . .