hi welcome to the group!
There are many possible causes of hair loss, if the hair only occurs once in awhile theres a good chance it could be caused by an alergy,does she also itch alot? have u checked your chi for fleas? as this is often one of the most common cuases.
another very possible cause is a yeast or bacterial infection.
This source is taken from animal.discovery.com, describing a similar ailment seen in a pug
Q: My pug's hair falls out like snow, and she has a strange odor. The smell is not coming from her ears, facial folds or anal glands. It's a strong odor all over her body. I do bathe her weekly and brush her daily. She still smells. What can I do? S. M., Jackson, MS
A: Veterinary dermatologist Dr. Lowell Ackerman of Westborough, MA says that if indeed you're correct that the problem isn't from your dog's ears or anal glands, it's very possible there's a bacterial or yeast infection. Ackerman says that frequent bathing cleans your pet, but it doesn't deal with a chronic infection. For that, you'll need an anti-bacterial soap, which you can purchase at veterinary offices. You'll have to bath your dog even more frequently, until you do eliminate the infection.
An allergy might inflame the skin, making it a ripe place for a bacterial or yeast infection to flourish. If that's the case, it's helpful to identify the source of the allergen. In order to do that, visit a vet familiar with treating allergies or a veterinary dermatologist. Certainly seeing a vet is important if there is significant hair loss, which means you're actually seeing bald spots.
Some owners report changing diets can help such problems; particularly a diet high in Omega 3 fatty acids and/or you may consider supplementing the diet with Flaxseed oil. Also, ask your vet about a possible thyroid problem. If there is an allergy, one easy first line of attack may be to treat with an antihistamine
hope this helps, let me know if u think it might be something else and ill try and get some more info for you
mia
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