I know this thread is forever ago, but I wanted to update....the training collar worked wonders. It's been nearly a year and no more chicken incidents and she rarely bothers them at all. Sometimes she sits and watches them but does not go too close.
While I would never trust her with them alone while they free range, like I can my mastador, it's been very good.
On the second bright side, she's seem to dispatched with all the OTHER small animals that ate my apple trees this winter. One rabbit and three squirrels this week alone! So the training collar hasn't affected her "other" hunting skills.
So if anyone is thinking about re homing their dog, think about the behaviour modification with the training collar. I'm so glad I did. She's really a great dog and I think I would have regretted giving her away.