Maybe. Dogs do not process fat as easily as humans do, so milk should only be served on occasion. Many dogs are lactose-intolerant, and should avoid all dairy products. However, reduced-fat milk without added sugar should cause few issues for most dogs. Do not ever allow your pet to drink chocolate milk, since chocolate can be fatally toxic to dogs, causing kidney failure.
If your dog has any unusual symptoms, talk to your vet about whether your dog could have a dairy allergy or lactose intolerance.
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