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Canine Behavior/12wk old English mastiff puppy


How do we get our 12 week old female english mastiff to stop biting all day everyday?

Congratulations on your new puppy! Such a fun time - and also a very trying time as we try to teach our pups to be polite and learn to live in our human society.

At this age, your pup is exploring her world with the only tools she has at her disposal - her nose and her mouth.

Part of being a puppy is learning how to use her mouth gently. We refer to this as learning "bite inhibition". In other words, she is learning how to inhibit her bite so that she doesn't cause harm when she doesn't mean to. And at this age, she has tiny, razor sharp carpet-knife teeth and so even a gentle chomp feels very sharp and painful.

There are a few things you can do to help her learn to control that mouth of hers.

First, be consistent in your interactions with her. If you're playing with her with a toy (e.g. Tug - which is a FANTASTIC game to play as it teaches cooperation, coordination and can be used to teach impulse control and practice skills such as Drop, Wait, Focus (eyes on me), Get it, Bring it), etc) and you feel teeth, the game stops. Drop the toy and say "ow. I don't play like that." I usually say this in my normal volume, but in an irritated/annoyed tone of voice. When I drop the toy, I pull my hands to my chest so they are not targets to be chased and I turn my head away to break eye contact. If necessary, I'll get up and leave the room for 30 seconds.

After a 10-30 second pause, I'll restart the game at a lower energy being sure to offer the toy again and praising the pup for grabbing the toy and not me. I like to use long toys so that there is quite a distance between her mouth and my hand. And if she starts to bite her way closer to my hand, I can just grab the other end and the game can continue. I also like to use large, plush toys that I can sort of bury my hand in so that the pup can't grab me while trying to grab the toy.

The key to this is consistency - you must interrupt the game EVERY SINGLE TIME YOU FEEL TEETH even if it's only incidental contact that doesn't actually hurt . Every person who engages with her must respond the same way and they must do it every single time so that she learns that across the board, teeth during play is unacceptable. If you find that she is just getting your hands all the time during play, then wear gloves. I specifically like cycling gloves because they have extra padding. This way, even if she gets you, it won't hurt so much and you still respond the same way - interrupt the game with an irritated, "I don't play that way", pause for 10-30 seconds before resuming at a lower energy.

One thing to keep in mind is that puppy jaws usually aren't strong enough to puncture our skin on their own. We get cuts during these interactions because we pull our hands away. If you can hold perfectly still - stopping the game and saying irritatedly your phrase of choice "I don't play that way" or similar, and then redirect back to a toy, you will end up with far fewer skin breaks.

If she's grabbing at your ankles/pants as you walk along, stop moving. The movement is what makes your feet/ankles a target worth chasing. So stand still. Then direct her ahead of you. You can do this by pointing and leading her along. Or you can toss a toy down the hall or across the room for her to go after, or you can carry a long toy for her to grab at and tug with along side you while you walk.

One thing to avoid is playing wrestle games where you're gently batting at her face and shoulders trying to get her to engage. When we play that way (which is a favorite way for men to play with dogs) we are teaching her to attack your hands as part of that play. Until she has learned to be gentle with her mouth, you should avoid that game.

On the flip side of all this, I think it's important for dogs to learn how to use their mouth softly with us. If you trip and fall on or near her, or accidentally kick her in the dark when you get up to go to the bathroom at 3am, if has no practice at using a soft mouth, she may well take a chunk out of you. If she's well practiced at using a soft mouth on people, then if she's startled or hurt, she's far more likely to make her point diplomatically and not actually bite you.

To that end, during quiet times, when the pup is relaxing with you, I will offer my fingers. If the pressure is soft and if the contact is brief, I will say quietly, "That's a good girl. I like a gentle mouth." If she's using just her front teeth or just the teeth on one side of her mouth, I will praise that. If she uses her entire mouth, if she bites and holds (outside of falling asleep), or if her pressure increases beyond very gentle contact, then I quietly, but irritatedly say, "ow. I don't like that" and remove my hand from her mouth for 10-30 seconds before offering again.

That pause during the game or these quiet-time tests is to help her have a clear understanding that her behavior halted her interaction.

NOTE that I do those tests when she's quiet and relaxed, not during a high energy game.

When she gets older and has demonstrated a clear understanding of how to play with high energy and still be gentle with her mouth, then you can allow incidental contact that doesn't hurt slide. Then you can test out gentle wrestling to see if she'll use her mouth softly during the game. If she is being very gentle, praise her and keep going (though keep the energy from escalating). If she uses too much force for your comfort, then tell her "Ow. I don't like that" and change the game - she's not ready for mouthy play yet.

You will likely find Dr. Ian Dunbar's book, Before and After Getting Your Puppy: The Positive Approach to Raising a Happy, Healthy and Well Behaved Dog to be super valuable. He has a whole chapter puppy bites, as well as other normal puppy behaviors that we all need to address such as jumping, chewing, potty training, etc.

I also have a blog I wrote a while back called Puppies Bite - What Can We Do About That?

I also have a video demonstrating how Tug games can be used to practice multiple other obedience skills and to improve impulse control.

I hope that some of this proves helpful. Please feel free to followup if I can be of further assistance.

Los Angeles Behavior Specialist

Canine Behavior

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Jody Epstein, MS, CPDT-KA


IF YOU BELIEVE YOUR DOG IS ILL OR INJURED, PLEASE CONTACT YOUR LOCAL VETERINARIAN IMMEDIATELY. THIS IS NOT THE FORUM TO ADDRESS URGENT MEDICAL ISSUES. I AM NOT A LICENSED VET AND HAVE NO DIAGNOSTIC SKILLS. ***I have been answering questions on All Experts for over 8 years now. I enjoy being able to offer assistance in this forum. I do need to be clear, though. If you’re looking for free advice about a specific behavior question, you MUST submit your question to me via All Experts. If you bypass All Experts and write to me directly through my website, I will ask you to submit via All Experts. On the flip side, if you’re local to Los Angeles and you wish to speak to me privately about an in person consultation, please go through my website. I appreciate your assistance in keeping my volunteer work on the volunteer site.*** I can answer questions about the following canine behavior issues: obedience, timid/fearful & fear-based aggression, nuisance behaviors, families that are expanding with either new human or new animal members and many other issues. If you have potty training questions please first read my trio of blogs at If you still have questions after reading the blogs you can post your specific questions here. PLEASE be as specific as possible when asking a question. Give me a detailed example of the situation - dog's behavior, body language, circumstances surrounding the issue, what the consequences are (another dog's response, your response), etc. I can only provide insight if I can get a picture of the whole scenario. If I ask for further details, please provide them. In person I would normally observe for at least 90 minutes to assess the situation and the dynamics before offering tools and suggestions to modify it. In writing it is ever so much more difficult. Thank you for your participation in the process.


I have been a professional obedience trainer for 9 years, and specializing in behavior modification for 8 years. I have owned dogs my entire life. I own my own dog training and behavior modification business called Nutz About Mutz.

I am a Certified Profession Dog Trainer - Knowledge Assessed (CPDT-KA), #2133301 ; I am a member in good standing with the Association of Professional Dog Trainers (APDT), #77763 ; I am an AKC certified Canine Good Citizen evaluator (CGC), #71253

Publications ; ; Multiple articles in the local pet magazine Pet Press (found across Southern California)

I have a masters degree (MS) in Animals and Public Policy, with a minor in Animal Behavior, from Tufts Cummings School of Veterinary Medicine. I also have 3 years of graduate education in Animal Behavior and Learning from UM-Missoula and UL-Lafayette. I continue to educate myself to canine-specific behavior through extensive reading, online interactive workshops, vidoes and attending canine behavior conferences, workshops and seminars. Beginning in March, 2017, I will be the Behavior & Training Manager at Second Chance Center for Animals in Flagstaff, AZ.

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