Heartworm Symptoms in Puppies

Heartworms are a parasitic infection transmitted to puppies by the bite of infected mosquitoes. Despite the term, the worms themselves only live in the heart in severe infections. Once the condition reaches this level, puppies can succumb to the effects of the disease including congestive heart failure. While most symptoms are only visible once the disease has progressed, it is still important to recognize them so that your dog can get immediate treatment.

  1. Coughing

    • Mild coughing from a puppy can be an indication of heartworms and the symptom will gradually become worse. This, like most heartworm symptoms, is an indication of heart failure. While there are other conditions that may cause coughing in dogs, a progressively worsening cough including the presence of blood in the saliva can mean the heartworms have progressed to an advanced stage.

    Lethargy

    • Puppies with heartworms typically become less active and more lethargic over the course of the disease. If a puppy begins to lie around excessively and shows no interest in playing, it could mean that heartworms are involved. The disease restricts blood flow and the delivery of oxygen to the muscles and generally makes the animal feel tired.

      If this lethargy is combined with the pulsating of veins in the neck while the animal is at rest, it may be a reason for additional concern and increases the likelihood that heartworms are the cause.

    Abdominal Swelling

    • Fluid retention in the lungs and the abdomen may result from a severe heartworm infestation. The coughing will likely be a result of this fluid and the unusual swelling of the abdomen is an additional sign of the disease.

    Jaundice

    • In some cases of heartworms, the parasites infect and damage the vascular system in the liver. This spread of the disease can result in jaundice in the animal. This symptom is most visible in the puppy's eyes, but may still be difficult to see. In humans the whites of the eyes turn yellow, and the same will happen in a dog. However, the coloring of a puppy's eyes may make this more difficult to see.

      By the time this symptom occurs, it is very likely that liver failure is imminent and the animal is very sick.

    Loss of Appetite

    • When heartworms infect a puppy, the dog often loses its appetite, as the condition gets serious. If a dog completely stops eating and drinking water, it can be a sign of several health problems, but combined with other symptoms listed here, it is likely that the parasitic infection is the cause.