So often dogs get punished for growling... I don't subscribe to this. I think it's a perfect communication. To stifle it, takes away one of dogs few ways to communicate with us. Please, take a few minutes to read this article and understand a bit more about this scary thing called growling!
The theory is that if a dog, at a young enough age is exposed to enough things everything will be vaguely familiar as an adult. Walking over one bridge will make the next ones a piece of cake. Sudden noises will be no reason for fear. Strangers aren't strange. Eating in odd places will not ruin a family vacation. Everything in life then becomes building blocks on a firm foundation. It greatly reduces fearful dogs. It increases dogs that are relaxed and able to learn in different environments. It is recommended before 7 weeks but will vastly improve the quality of your dogs life at any age. Here are some guidelines to start. The more experiences you can positively introduce your dog to, the happier everyone will be!
I cannot stress how important this is. It's not impossible to reprogram a dog, but truly you're overriding Mother Nature. The dog won't be at it's best and will often revert to it's true nature. Dogs placed in the wrong environment become projects not pets. Everyone is deserving of the best experience possible. So trying to convince a dog with a huge prey drive to stop chasing your three year old is going to be awful at best. Wanting a lap dog out of an aloof by nature dog will be sad. Please take the time to temperament test your dog. The puppies I have I test, you are more than welcome to re test or watch the test. Here's how it's done