With weeks 7 to 12 very critical in these months. From weeks 8 to 12 puppies go through their fear imprinting stage. Before this they were curious of things now they are fearful. During this stage you must introduce the puppy to different people animals and stimuli(sounds odours places). Ensure these introductions are positive experiences. The frequent positive social experiences when young will halt fear biting and antisocial traits. Any negative experiences during this stage will have a lasting negative effect and will be difficult to counteract. The most common reason for unprovoked dog aggression is lack of proper socialisation. If a puppy is not socialised after 14 weeks, more than likely it will be a problem dog and will have to be trained to unlearn its fears and anti social tendencies which will be frustrating and difficult for the owner. Socialisation will reduce the fear of the unfamiliar . A dog that was not socialised enough as pup can often be made into a good pet but it will be hard work. As the adage goes a stitch in time saves nine.
If puppy growls at a person or thing do not pick up and pet him/her. This will only intensify the bad behaviour. Cuddling will not get rid of the fear it will just make it stronger. The puppy will think that if it has fear it should growl. The growling could lead to biting and chasing. You must correct the puppy let it know that the growling at every new thing is not acceptable.
When you are socialising your puppy you must be calm, consistent and stern. Dogs can read human emotions so if you are feeling fearful anxious scared nervous etc the pup will pick up on it and will feel these emotions. Be confident when introducing new dogs, people etc. You are the pack leader and should be strong don't let the pup override you. A puppy has a playful growl and a defencive know the difference. Its best to introduce the puppy to new things when you can control the experience. Work at the pups pace when introducing a new person. Let the pup approach the new person,to sniff around and discover that there is nothing to be fearful off. If the new person is too full on and gets too close too soon it could cause a setback and induce fear and aggressiveness in the pup towards the new person. Encourage the new people to give treats. Walks are a great way for the pup to become accustomed to new people. Reward good behaviour with a treats praise etc. Do not socialise your dog with people who are not confident with animals this could undo your hard work. Make sure your pup is not isolated from the family give pup alot of company. Ensure that your pup does not spend time with aggressive people or dogs. Dogs like attention and will do annoying things to get it. If you have a problem with a dog jumping on you or the table pushing him off will not solve this. You must stop him before he starts and reward good behaviour. When pup attempts to first jump on you say sit and reward. Reinforcing good behaviour is vital.
The pup must learn how to interact with other dogs. Let the pup interact with vaccinated pups and adult dogs. The pup can learn skills of the older dogs. Learn dog language and body language. The pup should learn what other messages the other dogs are giving of and what messages to send of. Interrupt and separate your pup if their is any undesired behaviour with the other dog/pup. Make sure to always reward the good behaviour.