Can Mice Contaminate Dog Food?

Mice may be cute, but they tend to carry diseases, so keep them away from Fido's food.
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Dog food is something you want to feed to Fido and Fido alone. Unfortunately, hungry pest mice who infiltrate a bag of dog food can contaminate it with a variety of diseases. Sanitary feeding practices and proper storage should prevent mouse infestation of your pooch's food.


Wild mice carry a variety of diseases and bacteria, including hantavirus, leptospirosis, lymphocytic choriomeningitis, rat-bite fever, salmonellosis and tularemia, according to the Centers for Disease Control and Prevention. These conditions spread through contact with mouse droppings, saliva or urine. Mice, who tend to urinate and defecate where they eat, may leave urine and droppings in the kibble simply by sampling or creeping through any of your dog's food -- making the food dangerous for your pooch to eat. Just one mouse contaminates up to 10 times the amount of food it eats, according to the Indiana University School of Public Environmental Affairs.

Signs of Contamination

Contamination of your pooch's food can occur in your home but may also occur in pet supply stores or in a pet food manufacturer's facilities. Inspect the food and its packaging for signs of mouse contamination before giving any of it to your pup. Signs of contamination include dark ricelike droppings in the food, a musky odor and small holes in the dog food bag itself. In your home, you might find a small pile of dog kibble gathered by mice in places like closets and seldom-used drawers, according to the Humane Society of the United States. If you suspect your pooch's food is contaminated, don't feed it to him; throw it away.

Proper Storage

Dog food, namely dry dog kibble, attracts mice because the little guys can smell it and can access it by chewing through its packaging. Mice can squeeze through a hole the size of a dime, according to the Indiana Vector Control Association. Discourage mice and protect your pup's food by transferring it to an airtight plastic, glass or metal pet food container that mice can't access or gnaw through. Don't leave dog food sitting around. Remove your pooch's food dish 15 minutes after setting it down, storing dry food leftovers in an air-tight container and canned food in the refrigerator.

Discouraging Mice

Wash your pup's bowl after every meal and wipe down his eating area to remove stray particles of food. Seal up holes around your home that mice can use as entryways with caulk, metal or steel wool, the CDC recommends. Feed your pup only inside your home, not outside or in the garage where rodents can get wind of it. Never leave his food out overnight; this is when mice are most active. Mice are also attracted to feces, so remember to pick up after Fido when outdoors.

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