Something (my dog probably) got hold of chicken and tore crown, lots of blood, what do I do?

[Janus]

Title says it all really! Something got hold of one of my chickens today, they free-range all day in my garden. The dog (stupid lab) has been known to chase them but doesn't normally seem to get very close. Maybe she got lucky today?
Anyway her crown (not sure if right word but the floppy red thing on the top of her head!!) is definitely torn and there's quite a lot of blood around her neck.
She seems fine, was still pecking around when I saw her tonight and just shaking her head a bit. I picked her up but didn't want to clean her as thought it may stress her.
What do you think I should do? I think I should keep her in the cube for a day or two but the dog has free-run of the garden too (dog flap which is also the cat flap so needs to be in use). Do I hope the dog doesn't have a go again or keep her locked in a different room and supervise her visits to the garden, if possible? I am at home but often out and about with my youngest so the dog flap is great for ensuring she gets out to go to the loo.
Immediate worry is the injury to head, just wondered if anyone has had anything similar?
Thanks.

The only thing I can say is don't jump to conclusions. We thought our labradoodle was responsible for the demise of next doors chicken that landed in the garden but when the vet came out he showed us that the chicken had effectively committed suicide. So don't blame the dog and anyway if it was the dog the dog was only doing what comes naturally.

As to the chicken - if it is wandering around OK then I would leave alone but if in unhappy chicken then probably best off to putting out of misery.

If you are in and out all day then the dog should be OK to be shut in for a few hours without going out to loo.

Oh crikey clarice, can't imagine putting her out of her misery, they are more like pets really, certainly higher up the chain than the bloody rabbits!!
Being thick but what do you mean the chicken commited suicide? Do they really want to end it all sometimes?! Now I'm worried that mine isn't getting enough love, oh dear!!