Socializing your dog is one of the most important things you can do to ensure you raise a well balanced pup.
Most pups are generally taken from their litter at around 8 weeks when they’re weened off their mothers, after this, unless their new forever home has existing animals in it, they’re likely to find any form of animal uncomfortable or threatening.
Its important to note that whenever we talk about socialization, were not just talking about socializing with other dogs. Socialization comes in a range of different forms and its important your dog is socialized with a range of different things. This could be anything from Other dogs, other animals, children, sounds, the elderly and so on. The more types of animals, sounds and humans they’re exposed to, the more likely they are to be comfortable with it.
Reference: https://www.puppytodogschool.com.au/dog-training-school-sydney/