Could you please be more specific? In the past year, exactly how many deaths have you had due to illness, how many to presumed predators, and how long had you owned each animal before it died or disappeared?...
Background: What I have now is over 100 hatchery birds, various hatchery breeds, chickens, ducks, and turkeys, the oldest of which were bought in April of 2012. We've added a few more batches of chicks, poults and ducklings since last April, and have also hatched out some mutts here.
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I really don't think we've had any serious health issues with our flock ... very few deaths, predator or otherwise.
The thing is, if you have a serious predator or infectious problem, that needs to be addressed FIRST so that your "real" birds will be safe and well when you bring them to their new home. This thread is also a great place to get advice on those issues.
Best wishes,
Angela