My Chihuahua was raised first as a city dog. She was an adult when I got her and was an only pet for years. She and the chickens just don't mix. On the other hand, my Livestock Guardian Dogs, the Mastiffs were raised with all my animals and do great with my chickens. So, my 150 pound dogs are trusted with the chickens, it's the 13 pound dog that isn't allowed anywhere near them. On rare occasions the Mastiffs will hold the Chihuahua down with one paw and bark for me if someone lets her out. But, at this point, I don't let her out, she has a coyote proof run and she can get outside with her doggie door, she doesn't try to get out to the rest of the farm. It's always an adventure here!!