The most common reasons pets are surrendered to shelters are behavioral problems that are largely preventable through early socialization and appropriate training during critical developmental periods.
Behavioral problems in companion animals cause welfare harm on multiple levels: the animal suffers from chronic anxiety or fear; the owner-pet relationship deteriorates; and ultimately the animal may be surrendered and euthanized for a condition that was preventable. The critical socialization period is the most powerful lever for preventing these problems — the experiences animals have during this window shape their behavioral responses for life. This places significant responsibility on breeders, who control the critical period for puppies and kittens before they reach their new homes. Breeders who prioritize health testing but neglect socialization may produce physically healthy animals whose behavioral health is compromised from the start.