Can Hay Mold Hurt Dogs?

Most people who use hay as dog bedding will keep it in their outdoor dog kennels.
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Good quality hay can be a healthy, relatively inexpensive and environmentally friendly material for providing your dog plenty of clean bedding in his outdoor kennel. Unfortunately, good quality hay can be hard to find. If you don't know what to look for in hay or are not aware of the potential problems that go hand-in-hand with using hay as dog bedding, you can inadvertently exposing your dogs to hazard.

Dust, Mold and Allergens

The primary problem with hay as dog bedding is that low-quality hay is often dusty, moldy and full of all kinds of problematic allergens. Breathing mold is not good for humans or dogs. Exposure to mold can cause an assortment of problems, including coughing, wheezing, sneezing, difficulty breathing, lethargy, loss of appetite and nosebleeds. Mold spores can trigger allergic reactions in some animals.

Hay Mold

Hay molds as the result of being cut from fields too early or being bailed while wet. Hay can develop mold if it is stored in a damp location. Moldy hay has a foul, musty odor. You may notice mold discoloration when you look at a hay bale or break it open. Moldy hay may also appear to be very dusty, as mold spores are sometimes mistaken for dust.

Hay as Dog Bedding

Healthy hay is okay for use as dog bedding, but moldy hay can quickly cause health problems for your dog. If your dog snuggles into a pile of mold for a nap, he is likely to experience respiratory problems. If your dog can smell the mold and finds it offensive, he may avoid bedding down in the hay altogether. Pay attention to whether your dog tries to eat the hay bedding. Hay bedding is not a good addition to your dog's diet, moldy or not. If your dog is trying to eat the hay, you should not use it for bedding.


A wide variety of healthy bedding materials are available for your dog. If you are not 100 percent certain your dog's hay is clean and safe, you should opt for a different type of bedding. Shredded newspaper, old blankets or towels and commercial pet bedding pellets can provide safe bedding without the risks associated with hay. A few types of wood shavings are OK, but know for sure before using any.