This article is from the Fleas, Ticks, and Your Pet FAQ, by tittle@zmall.com (Cindy Tittle Moore) with numerous contributions by others.
When you find a tick, use tweezers to pick up the body and pull
s-l-o-w-l-y and gently, and the mouthparts will release. You should
see a small crator in your dog's skin, if you see what looks like
black lines, you've left the head of the tick in. At this point, if
your dog is mellow enough, you should try and pick it out. Otherwise,
you may need to take your pet into the vet, as the head parts will
lead to an infection. Ticks carry a lot of rickettsial diseases,
including Lyme disease and Rocky Mountain Spotted Fever, so you should
wash your hands thoroughly with soap after handling a tick.
Some veterinarians will put on gloves, smear one finger with a bit of
mineral oil and massage the protruding part of the tick for a minute
or so. The tick will back out.
Tips:
* Don't use any of the folklore remedies (matches, cigarettes, pins,
gasoline) that will irritate the tick. They increase the
likelihood that the tick will "spit up" in you, which increases
the risk of disease.
* Oil is not effective because the breathing requirements of the
tick are so small it could last hours covered with oil.
* The mouthpiece is barbed rather than spiralled, so trying to
rotate the tick out doesn't provide any advantage.
* The preferred method is to use special tweezers designed for that
purpose, and pull straight out.
Lyme disease (see below) is usually carried by tiny deer ticks (two
other kinds of ticks have also been identified as carriers) , which
are the size of the head of a pin. You must look yourself or your pet
over very carefully to find these kind of ticks. Other ticks can be as
large as peppercorns. This can vary depending on whether or not the
tick has yet engorged itself -- the deer tick can be as large as the
more familiar Dog Tick if it has had time to feed. So if you are in
doubt, preserve the tick in rubbing alcohol and have your vet take a
look at it.
 
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