Not socializing your dog
“Similarly a dog that has no human interaction, no fun, no playtime, can get depressed.” If there is something important dog owners forget to do is to let their pups make new friends not only with other dogs, but also with humans. One of the biggest problems with poorly socialized pets is a decreased quality of life. Walks, visits from guests and encounters with potential puppy playmates can be terribly frightening for dogs that aren’t used to be exposed with other dogs and humans.

Exposing your dog to second-hand smoke
The same that happens with humans can happen with dogs, canine lungs are not equipped to handle smoke being blown at them all day that is the reason why secondhand smoke can be a killer for dogs. Allergies, respiratory issues, heart disease and certain types of cancer can be some of the problems caused by toxins from cigarette smoke.
