nervous great dane puppy

Question
Hello!

I'm the owner of a 4 month old female great dane. I owned a dog before and I have prepaired for the training of a new dog so I probably couldn't have messed up that much. My dog still bites when she wants to play (anywhere.. skinn, clothes)and when I tell her to stop she get's even more aggresive and barks at me, jumps on me. She starts this behaviour when she's bored or wants something she can't get, eventhough she never got anything when she acted like that before. Sometimes she also starts digging on her bed and growling without any logical reason.
Another problem is that she doesn't trust strangers, she is scared of anyone who wants to pet her on the street eventhough I know she has never had a bad experience with people.
I would be glad for any advice.
thanks,
Alja


Answer
Young Labs, which I know best, and other puppies tend to very bad about
biting.  You see a litter of them, and all the ones that are awake are biting
another one or themselves.  I am not even sure they realize that when they are
alone, if they quit biting, they would quit being bitten.  At 3 to 4 months
they are getting their adult teeth, and it seems they spend every waking
moment biting or chewing.  One thing you can do at that stage is to knot and wet a piece of cloth.  Then freeze it.  The cooling will soothe the gums.  Only let the puppy have it when you are there to watch it.  I maintain a Lab's favorite chew toy is another Lab.  Otherwise they settle for any person they can.  They keep hoping to find one that won't yelp and jerk their hand away, or growl "Bad dog." and clamp their mouth shut.  Then offer a chew toy.  They keep trying despite hundreds of corrections.   Another good technique is to quit playing and go away.  Be sure to praise them when they are playing nice and not biting.

You just have to keep on correcting them, hundreds of times, not dozens.
Provide sturdy, safe toys such as Kongs and Nylabones.  Avoid things they can
chew pieces off and choke on them.  Keep them away from electrical cords.
Crates are essential for most young Labs and other dogs.

If the fear of strangers is recent, it could be the fear stage they commonly go through at that age.  In which case don't push her too much for now.  Although it would surprise some, people don't have the right to pet every dog they encounter out in public.  

You may want to have stranger give her a treat.  I have had some trouble with my puppies.  You can easily carry a little of the dog's kibble in a 35 mm canister to furnish strangers.