Pet hedgehogs are usually African hedgehogs. They were originally from central and eastern Africa, but most pet hedgehogs are now bred in captivity. Hedgehogs are insectivores and eat a diet mainly of insects, earthworms, slugs and snails. They are nocturnal, and hide and sleep during the daylight hours. At night they are quite active and in the wild will travel several miles looking for food. Hedgehogs are solitary in the wild, and pet hedgehogs will do better if only one hedgehog is kept in the enclosure.
One odd behavior that hedgehogs have is a practice of self-anointing. This is when the hedgehog puts a new object into his mouth, produces a lot of foamy saliva, and then licks the saliva onto his quills and skin. Needless to say the hedgehog will smell quite strongly after this. It is not known why hedgehogs do this, but this is considered normal behavior. Another unique behavior of hedgehogs is the ability to roll up into a tight ball. They even have a thick muscle that tightens the skin around the edges of their body when they roll up. They typically do this when they are scared, and they may remain rolled up for hours.
Three common health problems that cannot be ignored in hedgehogs are mites, cancer and neurologic disease. Hedgehogs are prone to skin mites and ear mites. Skin mites usually cause quill loss, itchy skin and crusty skin lesions. Some hedgehogs also become lethargic and eat less when suffering from severe mite infestation. Ear mites cause crusty ear flaps and sometimes crusty skin on the face. Some hedgehogs can have mite infestations without the obvious loss of quills and skin problems. Skin mites are usually treated with ivermectin injections or with selamectin (Revolution) applied topically to the skin. If the hedgehog just has ear mites, then eardrop medications (for cat ear mites) can be used or ivermectin or selamectin can be used just like for skin mites. It is usually necessary to remove the bedding from the cage during mite treatment. Newspaper or other paper can be used for bedding until the mites have been cleared.
Cancer in hedgehogs is common. In hedgehogs more than 3 years of age, cancer is very common. One of the most common cancers is the oral squamous cell carcinoma. These large masses in the mouth usually cause loose teeth and enlarged gums. This typically becomes a fatal problem. Hedgehogs are also prone to cancers of the reproductive tract, lymphoma of the gastrointestinal tract, mammary gland tumors, and other cancers of the abdominal organs. Some hedgehogs will have more than one cancer when they become older.
Hedgehogs are also prone to a neurological disease called Wobbly Hedgehog Syndrome. This syndrome affects roughly 10 percent of the pet hedgehogs. Hedgehogs with this condition become weak and wobbly when they walk. The disease worsens with time as more of the brain and spinal cord is affected. Signs can include falling over, seizures, muscle loss and paralysis. Paralysis usually starts in the rear legs and then develops in the front legs. The disease normally leads to complete paralysis in a few months. This syndrome typically starts in hedgehogs less than 2 years of age. Unfortunately there is no treatment that works for wobbly hedgehog syndrome, so euthanasia should be considered when the quality of life is lowered.