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Mice Problems

Mice are a big problem this fall. My husband wants to get rid of them with poison pellets, but I'm afraid our two cats might get into the poison. What's your opinion on a safe way to keep mice out of the house?

The poison pellets used around the home are as dangerous for dogs, cats, and even birds as they are for rats and mice. Warfarin, the active ingredient, is an anticoagulant. When ingested by a rodent -- or pet -- it causes internal bleeding and death. Warfarin interferes with the normal synthesis of clotting factors by the liver and will leave a dog or cat susceptible to bleeding problems for up to six weeks. I would be extremely cautious about using such pellets. Too often poisoned pets come into our hospital and the distraught owner says he thought the pellets were well hidden. Even if they are in a closed cabinet, the box can be bumped and send pellets rolling to the door. We recommend mousetraps as the safe and effective way to eliminate rodents. Also, try to find the openings where mice are entering the house (such as around clothes dryer vents) and block the openings. The only place you should even think about using poison is in a crawl space under your house -- and then only if it is sealed and inaccessible to pets and people. Also remember that dogs and cats can be poisoned by eating a dead chipmunk or other rodent which has undigested poison in its stomach. Some readers may wonder why your cats haven't done the rodent extermination job for you. Contrary to widespread believe, cats do not hunt mice instinctively. Any good mouser has learned the skill from its mother before it is weaned. If it is not taught as a kitten, it will never want to hunt mice. You can take some comfort in knowing that yours is not the only house that has been invaded by mice. As the weather gets cold, they head indoors to get warm. This is especially true in new housing additions.