How old does a shih tzu puppy have to be before it leaves its mother?

I think around 8 - 10 weeks should be an appropriate time. Once the puppy has been weaned from it's mother and is eating solid food.
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The propper age that most breeders let puppies leave the mother is at 8 weeks of age. Because those two weeks between 6 and 8 weeks are so important in the building of the pack, it is better for the puppy to stay with its littermates untill 8 weeks old.
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For a STABLE dog later in life, keep mom and siblings together for at least 8 weeks. Even when the mom has little to do with them, the learning from being with the littermates is valuable.
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Vet Tech/dog breeder

At least 8 weeks - this allows for socialization with other dogs and the puppy to learn bite inhibition with siblings.
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All dogs are the same: No younger than 8 weeks, preferably more like 12 weeks. Puppies taken from their mothers too early can exhibet a lot of behavioral problems as adults (seperation anxiety, inappropriate "humping", dog-aggression, poor socialization, lack of bite-inhibition). The mother and littermates of a puppy have a lot of valuable things to teach and taking the puppy away too early means that you'll have to teach them these things instead. Best to let Mom handle it.
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3 months I think.

OMG this reminded me of a joke. What do u call a Shi Tzu and Bulldog mix?

a BULLSH1T!!! LOL!!!!!!!!!!
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puppies are usually weaned at 8 weeks. So you have 2 months to wait.
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It's the same time around any pet. It's usually 8-10 weeks. That gives them time to notice their surroundings and explore more.
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8 weeks minimum, 12 weeks is better for the pup
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A minimum of 8 weeks but it is much better to give puppies 12 weeks…allows for additional group behavior bonding, mental growth with siblings and general overall well being.
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Bread Samoyeds…4 National Champions…all from litter kept at least 12 weeks

at least 6-10weeks for all dogs
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6 mounths
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Every puppy no matter the breed has to be no less than 8 weeks of age before being separated from their mother. This is very important for their emotional development, having breed and owned Shih-Tzu's for 15yrs my 9 yr old girl who is an absolute delight, she has a full coat which personally I find easier to manage. To have the pleasure of owning a Shih-Tzu is a 12yr + commitment they have a long coat and can be high maintainence, choose wisely.
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10 WEEKS!! Time for you to RESEARCH!!! & get supplies!
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