Is my 10-week-old puppy's rough play and biting normal behavior?

At ten weeks of age this is still very normal behavior. If Safiro is getting too excited, taking a time out and stopping all play/walking away until he's calm again can help to teach him that getting too excited results in the fun ending, and that calm behavior is rewarded with more play time. Working on some impulse control training (such as airplaning treats, taking and dropping toys, taking treats nicely, sitting politely -- YouTube has great tutorials for all of this) can also help with over excitement and biting behavior.

This is indeed common in puppies (and some adult dogs). When Julius gets riled up or too excited, stop all play until he calms down. If he bites, a stern "No" or "No bite" should get him to stop. Praise and reward him when he complies. Be firm and be consistent.

This is very normal puppy behavior, but it’s important to discourage this ‘mouthiness’ so you don’t have an adult dog who tends to by mouthy or nip. This website has some great training tips in general, and this article addresses this problem specifically: https://drsophiayin.com/blog/entry/puppy_play_leads_to_nip_marks_on_hands_and_arms/

Hello, rough play is ok as long as they are not showing teeth or biting each other. It is also ok, as long as both of them want to play and not one picking on the other. If you think they are showing some aggression or if it is getting too rough, you can separate them for some time. Also ensure they have enough toys, especially chew toys so that they can redirect their rough play to those chew toys in particular. Hope this helps.

Yes, it's very normal for a 5-month-old puppy to try and grab whatever he can with his mouth - this is how puppies explore the world, and how they instinctively want to play. I would recommend getting some nice long, floppy rope or fleece toys that you can carry with you for him to grab when he gets excited, rather that biting your clothes. This is a better option than scolding him, which tends to just make the pup more excited and often makes things worse. If you need some hands-on guidance to help you with this, you can search for a qualified reward-based trainer in your area here: www.ccpdt.org

Oh dear! Growling when you pick her up is a major red flag for future problems in a puppy this age - this is not normal, and needs more help than just socialization. From your description, it's hard to say if her behavior with the other puppy is normal play or aggression. I would strongly recommend making an appointment with a veterinary behaviorist who can evaluate her in person and help you put together a plan to work on these issues - it's best to do this as soon as possible, since early intervention gives you a much better chance of being able to change this behavior before she grows up. I'm not sure what part of Canada you're in, but your regular veterinarian should be able to help you find out where your nearest board-certified veterinary behaviorist is so that you can make an appointment. In the meantime, I would try and avoid doing anything that tends to make her growl - instead of picking her up, for example, use treats to encourage her to come to you. I would also not recommend any kind of punishment for this behavior, as this has a high risk of making things worse over time. The behaviorist can help you identify what kinds of situations tend to trigger the growling, and will put together a training plan to work on this issue.

Biting and mouthing during play and at other times including when you pet her, when you are walking, etc. is completely normal behavior for a puppy this age - this is how puppies explore the world, and how they instinctively want to play. I do not recommend scolding her for this or telling her "no!", as this often makes dogs more frustrated and worked up, and tends to make the problem worse. Instead, redirect her to one of her toys and encourage her to bite the toy instead. Make sure that she has a variety of different toys available to provide an appropriate outlet for this behavior - long floppy rope or fleece toys for tugging, plush toys for biting and carrying, and smaller toys or balls for chasing and fetching. She also needs lots of different things to chew on - bully sticks, rawhide chews, cow or pig ears, and puzzle toys such as a Kong stuffed with peanut butter are all good options you can try. This behavior normally resolves on its own as puppies get older, so there is no need to attempt to punish her for it - just redirect her to something more appropriate, and be patient while she learns :)