Do male Shih Tzu dogs still mark their teritory by peeing after being spayed?

Males aren't Spayed, they are Neutered.

Marking indoors is a training thing done on your part.
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Neuter it YOUNG and it's less likely to be a problem. Beyond that, training.
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Male dogs are not spayed, they are neutered. Some will not "mark" if they really haven't done it before, but it depends on the breed and more so individual dog. My little guy went behind all the big dogs and "marked" and we was neutered at 3 months. Shelters rules. Heck my female did it after being spayed too. It's all about dominance.
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It depends on the age and sexual maturity of the dog. The younger the dog is when it is desexed/neutered (spayed is the term used for female dogs) the less likely it will still mark its territory.

Just out of interest, female dogs also mark their territory. They tend not to be so obvious about it but some even lift their legs while they squat so that they can mark more effectively!

You can train a dog not to mark inappropriately, housetraining is a must for any dog anyway.
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After neutered, this situation might happened also.But you can potty training him in order to avoid marking territory problem!
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http://www.dogcareschool.com

Yes the dog will continue to mark many spots to let other dogs know hay Ive been here and will return just because you fix a dog does not mean he/she wont mark places they go this is normal for the animal to fix means, so neither sex can produce babies. and you spay a female and neuter a male.
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