Endoparasites of Dogs
A parasite is an organism that lives on or in a host organism and gets its food from or at the expense of its host.
Internal : Heartworm
Intestinal : Hookworms, Ringworms, Roundworms, Tapeworms, Whipworms,
Coccidia, Giardia, and Spirochetes (non-worm parasites)
External : Fleas, Ticks, Lice, Mites
Heartworms enter a dog’s bloodstream from the bite of an infected mosquito. The worms mature in the dog’s heart (they can grow up to an amazing one foot in length), and clog it. Inflammation in the dog’s arterial wall disrupts blood flow, making the heart have to work harder. Once blood flow slows sufficiently, a heartworm-infested dog develops a mild, persistent cough, may become fatigued after only mild exercise, and suffers from a reduced appetite. The end result can be heart failure.
Most dogs harboring this parasite do not have clinical symptoms prior to the worms being detected via screening tests. These tests are usually done during routine veterinary check-ups. The test is so sensitive that it can detect a single worm in a dog’s body.
Transmission occurs through other infested dogs, mosquitoes to carry the parasite, the right temperature
Treatment for heartworm is expensive and hard on the dog, and must be administered by a veterinarian. In rare cases, surgery will be required to remove them.
Hookworms live inside a dog’s digestive system, and are acquired either by puppies from their mother (when nursing) or by adult dogs swallowing the parasite’s eggs, or having the hookworm burrow into the skin. Hookworm larvae live in soil, and can be ingested when the dog comes in contact via eating them or through routine self-cleaning. After attaching to the lining of the intestinal wall, the hookworm feeds on the dog’s blood. The resulting blood loss can have serious effects, especially on puppies. Hookworm is detected by examination of a stool sample under a microscope. Infection can be prevented by keeping your dog’s environment clean.
As with a number of intestinal parasites in dogs, diarrhea and weight loss are common symptoms of infection.
Ringworm is actually a fungus, not a worm. Because of their still-developing immune system, puppies less than a year old are more susceptible to ringworm. Adult dogs that are malnourished or stressed, or low immunity are also at risk, and the ringworm fungus is easily transmitted. An infected dog will develop lesions on his head, ears, paws, and forelimbs. The lesions cause circular bald spots which sometimes look red in the center. In mild cases, a dog might suffer only a few broken hairs. In severe cases, the infection can spread over most of the dog’s body.
Treatment depends on the severity of the infection. Ectoparasites can be eradicated by medicated shampoo or ointment to kill the fungus in mild cases. Severe cases may need oral medications, in addition to clipping the fur.
Roundworms are an extremely common parasite, and again, puppies are most at risk. They look like white, firm, rounded strips of spaghetti, one to three inches long. For examination, sample should be collected from stool.
Rohit Juneja*, Arpita Sain
ARAWALI VETRINARY COLLEGE (Affiliated with Rajasthan University of Veterinary and Animal Sciences, Bikaner), Jaipur Road, Bajor, Sikar, Rajasthan, India