When a tick bites your dog, the tick does more than just bite -- he digs in and feeds nonstop, gorging on your pet's blood and injecting his saliva into the wound. The saliva, not the blood consumption, transfers disease to your dog. The longer the tick is there the higher the odds he'll cause lasting harm. When you remove a tick, though, he can't go on doing damage.
Once you remove a tick, he can't keep harming your dog -- even if some of his head is left behind. This is because his saliva, which enters your dog's system only as the tick is alive and feeding, transfers diseases like Lyme disease. After the tick is out, though, your dog may show symptoms of harm caused by the attack, like an allergic reaction on his skin at the feeding site. He may show symptoms of transferred illness, like arthritic joints, fatigue and lack of appetite. If your dog has been bitten by a tick, make an appointment with your vet to rule out tick-borne diseases.
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