Puppies are naturally rough when they play. They jump, paw, bite and climb on each other and they transfer the same behaviors to the people they interact with. It is rarely a sign of true aggression. It's not uncommon for new puppy owners to see all the biting and chewing and growling and believe their puppy is aggressive and not bonding with them. Usually, the puppy is fine, but needs guidance from its owners to learn to interact appropriately with humans. If you are concerned about aggression problems with your puppy, seek professional help, even if it turns out to be simple puppy play. Either way, you and your pup both need to learn proper ways to interact.
Write down a description of the problem behaviors as they occur, including as much detail as possible about what was happening at the moment and about 10 minutes before the behavior.
Take your puppy to the veterinarian for a thorough examination. Sometimes hidden medical problems can cause aggressive behavior, or slow the bonding of the puppy to its new family.
Call a veterinary behaviorist or a trainer with experience in behavior problems for an evaluation of your puppy's behavior. Though it is common for new puppy owners to mistake normal puppy play and behavior for aggression, it is imperative that a professional evaluate the puppy to be certain this is not a true aggression problem and to instruct you in the proper handling of your puppy. If you have mistaken puppy behavior for aggression, then it's clear you need some instruction in reading your pup's signals and preventing future behavior problems.
Train your puppy at home and also in a kindergarten or obedience class. Continue training classes and working at home with your pup for at least the first three years.
Exercise your puppy daily. If a puppy is playing too rough and is hard to control, more likely than not it's not getting enough exercise. Puppies need on-leash and off-leash exercise each day, as well as some playtime with other puppies. Playing with other puppies helps your puppy to learn dog manners, which helps your puppy behave better with people. Find a clean dog park that has a separate play area for young puppies, and take your puppy as often as possible. Daily is best, but at least three times a week is a must.
Give your puppy attention and training treats when it is calm, sitting, playing with its toys or otherwise behaving positively. Ignore the pup when it is jumping, biting or whining.
Put the puppy into the crate or a puppy exercise pen on a regular schedule for napping or chewing on its safe chew toys. Don't leave the pup in a crate for long periods of time. It should be used a you would use a playpen for a baby. Put the puppy in the crate when you can't supervise it, when it needs a nap or is over excited and needs to calm itself by chewing.
Avoid roughhousing with your pup, and teach your children to never run or squeal around the pup. Rough play teaches the puppy that rough play is acceptable. Dogs can't tell the difference between playing with a person who likes rough play and one who doesn't like rough play or is easily hurt. Tug is OK, but you must be the leader. Don't let children roll on the floor with the puppy or play chase with it.