Parasites run rampant in the outside world. While a safely contained pet may still contract internal and external parasites, his chances are much less than a dog who runs free in the neighbourhood or wilderness.

External Parasites

The Obvious


• Fleas

Oh those evil little bloodsucking fleas! Fleas are caught by an animal coming close to a flea-source, either another animal of any species, a person, or even stepping on flea eggs on the ground. Fleas bite, make your dog scratch like mad, and can even carry diseases, and worst of all Tapeworms.



• Ticks

Ticks must be one of Nature's practical jokes. Serving no apparent purpose other than to feast upon their hapless victims, ticks are carriers of Lyme Disease, and other nasty diseases. Ticks like to hide in the grass and wait for an unsuspecting passing animal or human to climb on to.

The Not-so Obvious


• Cheyletiella Dermatitis

This is a small mite that resides on the outer layer of skin in both people and animals. This mite is easily passed through contact with an infected animal, and can cause scratching, fur-loss, and scaling of the skin.


• Sarcoptic Mange

Mites again. Sarcoptic mites burrow under the skin to lay eggs, which hatch then work their way up during their various life stages. A full life cycle of a sarcoptic is about three weeks. These nasty critters cause reddening of the skin, scaley and crusting skin, loss of fur, and are extremely contagious.


• Ear Mites

Ear mites are itchy, irritating little mites that like to hang out in your dog's ears. Highly contagious, though it is sometimes hard to tell if your dog has them. If your dog is scratching his ears bloody, if they are painful to touch, or even if they smell bad, please have his ears checked for mites.

Internal Parasites


• Hookworm

Hookworms are evil little creatures that feed off the intestinal walls. They are passed to other animals through soil, where eggs have been laid. These are incredibly easy to contract. The larvae that live in the soil can enter the body through the feet and travel throughout the system until they reach the intestines where they stay to feed off of blood and lay eggs that shed once again, in feces and contaminate the ground.


• Tapeworm

Tapeworms are long, segmented worms that live in an infected person's or animal's intestines. These are most often noticed when the worms start to shed segments full of eggs, which are often found around the anus, or in stools. These segments look like grains of rice when dry, but are squishy and may be moving when fresh. Tapeworms are spread by ingesting fleas that have eaten the eggs, or by ingesting egg sacs from feces.


• Roundworm

The most common of internal parasites beside Tapeworms, roundworms frequently infect pets. They look suspiciously like thin spaghetti noodles and can often be found in feces with the naked eye.


• Whipworm

These are long, whip-shaped worms that are ingested either from the feces of infected animals, or spread through other bodily fluids. They are found in the colons of animals, and shed eggs through feces approximately three months later.


• Coccidia

This is an internal microscopic organism that is often present where large numbers of animals gather. This organism causes watery bowels, upset stomach, and other ailments. In the very young it can be responsible for growth deformities.

Free Range Dogs
Part 1: The Perils of Letting Your Dog Roam Loose in the Neighbourhood. Part 2: http://dogs.about.com/library/weekly/aa090102b.htmParasites Your Dog can Catch if He Runs Loose Part 3: Infectious Diseases Part 4: Aggravated People