Amybeth, you can train a dog to leave the chickens alone. We have a GSD whose German sire was 4th in the world Schutzhund trial competition. If they see you as their leader and understand that those are your chickens, they will protect them out of obedience to you. It does take a lot of patience and consistent training and you don't trust a pup alone with them until they are mature mentally. Sometimes when they are young, they may make mistakes, but you use that as a learning experience to reinforce your rules. It's not true that once they kill, they have the taste of blood and will do it again. Our English Shepherds are also dogs that protect the family and livestock, including chickens, as well as herd and hunt predators & varmints.
I'm sorry about your hen. The farmer near here with sex link chickens free ranging in his fields is losing huge numbers of them to the heat.
That's so nice of you to offer the Basque chicks. I appreciate it but can't handle having another breed here. I don't know how people breed so many different kinds and keep everything separate.
Love the pic of the chickees looking at the lizard.
Kim