Fighting hens.....oh, what to do, any thoughts?

[jerseygirl1]

OK, I have a mixed flock of 20 hens, five bantams (not the problem, obviously) but the 13 standard size are all laying, I have two white leghorns that are now completely bloodied within days. I isolated one for a few days, and she's fine, now it has happened to the other one. I only have two.
The only thing I can assume is that they are taking too long in the nest box. There are five nest boxes, only two are being used by all 13 hens. The reason I think it is the leghorns taking too long, it seems there is blood around the nest boxes after they lay an egg. They are bloodied around their combs and eyes. I fell horrible, I'm not sure which one of the remaining 11 is doing it, and have no clue as to how to find out. The latest battle was this morning, within an hour after I went back in the house. I see no fighting at all when I peruse thru the window checking on them unnoticed, and when I observe them in the coop, so it's not a matter of them seeing me and backing off. SHould I isolate just the two leghorns? I have a large dog cage in the coop to isolate a few, but I fell awful about the two bloodied ones. I mean, they are flighty anyway, but still they are good hens. They also have the largest combs of all the hens, maybe that could be why? Help

 

[High Roost Ranch]

That's what I would do is remove them, since you can't seem to find the offenders. Or perhaps add additional nestboxes separate from the current boxes in a different area. I've not known my leghorns to take longer to lay, they are in and out in a flash.

 

[jerseygirl1]

This last one really took a beating - I wonder if getting a full size rooster would solve the dominant hen problem