Hen injured, Help NEEDED!!!!

My buff orpington hen was attacked by a dog at the end of last week and we thought she was okay. I finally caught her today when I noticed her fethers were dirty around her chest and found a large injury there. There is a big wound and what looks like her exposed/open crop. I can see bits of grass and grain. She has been getting around okay, and my husband and I were wondering if chickens can recover from this type of injury. If so, what can we do to aid the healing? We raise chickens mainly for eggs and tick control, but occasionally will harvest them for meat (excess roosters usually). If we need to harvest her, I want to make sure that she doesn't become so far gone that the meat is wasted. I would like to save her if it is at all practical. Thanks.