Thank you all for your your kind thoughts and advice, I was very aware that the dog may come back so after much soul searching my wife put out a message on Facebook to see if anyone could re home my last Chicken.
A big thankyou to Anne-Marie, who lives a few miles away and offered to take her for me. We took her round this morning and introduced her to her new friends, a Duck and another Chicken, it was the most difficult thing I have had to do. A couple of hours later we got a text letting us know that she had settled in fine with her new buddies and had gone into her new Ark to lay, I am now looking forwards to seeing picturtes of her in her new home up on Facebook soon.
I will get some new Girls at some point in the future, but only when I can be sure that the garden is not only chicken proof, but also Dog proof. It is a terrible way to end your days and I will be as sure as I can that it will never happen again.