INTERNAL PARASITES ARE A HEALTH CONCERN

All puppies need to be checked for internal parasites during the first visit to the veterinarian. This is done through a microscopic examination of the stool or feces of the puppy. A fresh fecal sample (within 24 hours old) should be taken to the veterinarian at every puppy visit. The importance of this examination is to protect both the puppy and any children in the household from being exposed to worms or parasites.

Roundworms

• Roundworms or ascarids are caused by an intestinal parasite called Toxocara canis. This is a large robust worm, which can be seen occasionally in the feces or vomit of the puppy. These parasites can be transmitted through the placenta of the mother and the puppies can be born with the worms. They can also be spread orally by direct contact from contaminated soil, food, or feces through exposure to the microscopic eggs of the parasite. Puppies can have a pot-bellied appearance and look unthrifty. They can also exhibit signs of colic, vomiting, and diarrhea since the parasites interfere with the motility and function of the gastrointestinal tract. Coughing can occur in the puppy if the worms migrate into the respiratory tract. Occasionally roundworms can cause serious health problems in a puppy including death. However, the parasite is easily removed through a series of oral worming with fenbendazole (Panacur) or a pyrantel combination. Entire litters are affected and all the puppies should be treated along with the mother. Children are infected by exposure to the eggs of the parasites through oral contact with an infected environment. An example would be obtaining an infection from a sandbox or playground, which contains the eggs of the parasite in the soil. Children can also get the feces of a puppy on their hands than swallow the eggs in food if their hands are not washed. The name of this infection in humans is called visceral larval migrans due to the migration of the larvae into the liver, lungs, and eyes of children.

Hookworms

• Hookworms are nematodes belonging to the species Ancylostoma caninum and Ancylostoma braziliense and live in the small intestine of dogs. These worms can be passed from the mother to the puppies through the milk or be spread through contaminated feces, soil, and water. Hookworms are voracious blood sucking parasites and can cause life-threatening anemia in puppies. They also can cause bloody diarrhea, vomiting, lethargy, weakness, pale mucous membranes, and death. Coughing can occur if the worms migrate in lung tissue. The parasite can also enter the puppy through skin penetration especially from contaminated soil. All puppies and the mother should be treated with fenbendazole or a series of worming with a pyrantel combination drug. Children become infected through contaminated feces or soil by penetration of the parasite through the skin (cutaneous larval migrans). The parasite burrows in the skin of the feet, buttocks, legs and back that causes an intense itching in humans.

Whipworms

• Whipworms are caused by the parasite Trichuris vulpis and the infection usually takes approximately two to three months to become noticeable in the puppy. The eggs of the parasite are spread through contaminated feces or through the environment. Unfortunately, the infective eggs can remain viable in the environment for years. Signs in the puppy include vomiting, diarrhea, gas, colic, poor coat, and lethargy. There is no migration of the parasite in pets and humans cannot be infected by this parasite. All infected puppies and adult dogs should be treated with fenbendazole (Panacur), or a pyrantel combination drug. Usually the pets need to be treated a second time and the stool monitored every few months for recurrent infections.

Coccidiosis

• Coccidiosis is a parasitic disease caused by the microscopic organism Isospora canis. Other species of this protozoan can also cause this disease. Signs of infection in the puppy include diarrhea that can be watery, bloody, or mucoid. This organism can easily reproduce in the environment and recontamination is an ongoing problem. All dogs in the household should be treated with sulfamethoxine (Albon) for 5 to 10 days. Multiple treatments may be needed to kill the microorganism and multiple fecal examinations are needed. Coccidia are commonly found in puppies from pet stores or breeding farms. Spread to humans does not occur. Dogs can also get infected from eating feces from rabbits.

Tapeworms

• Tapeworms occur in the small intestine and are commonly seen by the owner as small rice like segments around the anal area of the puppy or in the feces. Puppies can also have anal irritation, which can cause rear end rubbing on the ground. There are many species of tapeworms, but the most common types are transmitted to the puppy through ingestion of a flea, rodent, or rabbit. Treatment is by oral or injectable praziquantel (Droncit) or a combination drug. Flea control must be practiced or the puppy can be exposed on a continual basis. Also, dogs should not be allowed to kill and eat wildlife.

Giardia

• Giardia is a protozoan infection spread by Giardia canis through contaminated water or feces. This organism lives in the small intestine and causes intermittent or chronic diarrhea, which may or may not contain blood. It also can cause an unthrifty puppy with poor growth. Kennels, pet stores, and breeding farms can have a chronic problem with this parasite. Diagnosis is obtained through observation of the parasite in a direct smear from the feces of the puppy and/or from a fecal antigen test. Treatment can be difficult and multiple treatments may be needed with metronidazole or fenbendazole. Giardiasis is the most common intestinal parasite of people and the organism can be spread from dogs to humans. People have their own species of Giardia and this parasite frequently lives in lakes and streams that are contaminated with feces of wildlife.

Kathleen Stryeski, DVM

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