What is Heartworm?
Heartworm is also known as Diro laria immitis. It affects dogs, cats, ferrets, foxes, wolves and sea lions. It is passed from the bite of a mosquito to the animal. The adults live in the animal's heart and their offspring (micro lariae) live in the blood vessels. The life cycle of heartworm is 6-7 months, so dogs don't test positive or show signs of disease until six months after contracting the disease.

What are the Symptoms?
Most times there are no symptoms, however, advanced disease symptoms include:

•Obstruction of Blood Vessels
•Weight Loss
•Decreased Exercise Tolerance
•Unproductive Cough
•Labored Breathing
•Fainting
•Distended Abdomen
•Congestive Heart Failure
•Enlarged Liver

Why Should You Test?
We recommend yearly testing for the presence of adult worms. This ensures that there hasn't been a lapse in the prevention. The treatment for the adult infestation is different and more serious than the microfilariae. A lapse could be caused by prevention started too late, ended too early or missed, or late treatments that the dog may not have ingested.

Acknowledgement:
- A Missouri Valley Veterinary Clinic Information Sheet.
Reprinted with the kind permission of Missouri Valley Veterinary Clinic
(All Creatures Great and Small), Bismarck, ND.