What do you dog people think about a rottweiler/lab mix as a chicken/farm dog?
Lab breeding is iffy for poultry because they are bred to be bird dogs in the first place.
Individuals *can* be an exception though. Even if you decide to go for a Pyr or an anatolian don't leave the puppy unsupervised with the birds. My Pyr boy mistook one of my ducks for a squeaky toy once (bird was fine. No problems now, dog or bird) and a contact's anatolian used to catch the chickens in his paws and lick them until their hearts exploded in fear when he was a puppy.
Breed is not most important issue. I have always used short-haired hunting dogs of some sort (most were black and tan hounds) and presently a German short-haired pointer which is decidely used as a bird dog in this country. Even the latter can do quite well if it stays on site. In east-central Indiana the coyotes are going to be bigger so a larger dog needed to deal with them consistently. All dog breeds can be a problem if not properply imprinted or trained. The typical livestock guarding dog is typically prepped by imprinting while the hunting dogs require more in the way of training although imprinting can be used with them as well. Key point to remember is that none o fthe currently used livestock guarding dogs were developed to protect poultry and most breeds of dogs have at least some ancestry (thousands of years worth) where they where used extensively to defend the farmsted. Protecting poultry has a lot more in common with defending a farmsted than a mobile flock of sheep or goats.