Would it be safe for a Miniature Schnauzer to?

Dogs play with dogs. It doesn't matter what breed….He can play with Great Danes and Mastiffs if he wants too. It all depends on how well the dog is trained, and socialized and the dogs disposition.
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as long as they are introduced first then kept a close eye on them for the first few days they should be fine
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2 dogs grandpa a breeder

Yes if they dont fight and you properly socialize them.
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if your going to your friends house with your dog (first time meeting) i think id introduce them on leash's on mutual ground. like at a park or down the block neither should feel like it needs to protect their ground then
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My Schnauzer loves Yorkies.
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