Hi - we have a choc. lab/australian shepherd mix. When she was young she would chase the chickens non-stop. I had to stay with her the WHOLE time when she was a puppy to discipline her IMMEDIATELY until she started behaving properly. Now, she is older, and the chickens are safe. She will sometimes herd them, which they don't like, but doesn't try to eat them anymore. The lab in her has hunting instincts, the aussie is a herder. My chickens are now safe, but she has recognized them as ours... It took her over a year of CONSTANT vigilance to get her trustworthy. While she didn't chase them constantly, you couldn't trust when she would go after them, or if she was trying to herd them or hunt them. NOW, at 3 years old, she is fine with any ADULT chicken, but not with juvenile or baby chicks. She considers baby chicks fluff snacks (although she hasn't gotten any) and the juvies I simply watch her around to make sure she doesn't hound them or scare them. Each dog will have its own traits, some are known to be good with other animals, some are NEVER to be trusted, etc... you do have to be careful with breed. Most little dogs (chihuahua's, dauchunds, terriers for intance, were ALL breed to attack and chase down small rodents/pest animals - their instinct will be to chase and KILL little birds/rodents.) Larger dogs, if you get them young, tend to be better with training for animal care/children. Australian shepherds are herding dogs, so while they aren't trying to kill animals, their instinct is to follow and hound them over and over - also, they are ACTIVE and take longer to mature. Labs are companionable, but were breed for hunting AND companionship both, so while you can train them for animal care, it can take longer because of their instinct for the hunt. Hope that helps... the main thing is patience, get a calm older dog, or a young puppy - but WATCH either and train them the whole time they are loose until you know they are trustworthy with your personal animals. They might still go for someone else's but they should start trying to protect the ones they know. : ) Best of luck!!!