Systematic studies have appeared in the veterinary literature documenting these effects. Castration lowers the probability that an adult male dog will exhibit undesirable male-like behavioral patterns. Like the male, spaying the female will not affect the ability to perform watch-dog activities. The belief that dogs get fat and lazy after neutering is largely a myth. Consult your veterinarian for the best age when this should be done.
Child is the father to man.
These are famous words which indicate how important the early life experiences of an individual dog might be. Generally speaking, the experiences received by your dog between the fifth and tenth week are the most crucial. Most important, puppies who are not properly socialized are extremely difficult to train. Learning plays a key role in determining the kinds of behavior your puppy exhibits. Obviously, your dog in the future is a large part a result of the learned experiences acquired in the past.