Dead Hen with a lot of puss around her vent found - Wondering if Disease?

[Beamerz]

I found one of my red hens mid day near the coop water feeder just inside the automatic door with a large number of big feathers around her. She was stiff already and had a lot of brownish puss around her vent. She was in the countdown last night when I put them to bed at 5:30. I have an automatic door that opens in the morning and I didn't look inside there until mid day when I found her there . Most of the feathers around her were large feathers.. not much of the down. I'm confused can anybody guess what direction I might go in? If it was rats they would have eaten her but not eaten..just stiff. Thanks for any feedback from more seasoned folks than I...I'm only in my 4th year.
Beamerz

 

[CHlCKEN]

Did it look like it could have been egg material around her vent?

 

[Beamerz]

Did it look like it could have been egg material around her vent?

No I don't think so, but I'm wondering if she was maybe egg bound and got infected. Her body was too stiff to tell by the time I found her... I recently intergraded two younger flocks with my mixed age flock, and my numbers got high enough so as not to "screen" everyone as well as I should have at bedtime.
I have not yet culled my young roosters, so I'm now wondering if maybe they might have been rough or somehow caused a problem for her, as they have just become very active. I've never had more than two roos at a time and my senior roo who is 5 is tired at 4:30 and ready for bed some days... My total count is now 33 birds I'd added 15 hens in Jan and then raised two clutches myself since June which added 4 hens and 3 roos to the two older roos. How many roos do you all keep if you have a moderate sized flock and how do you "police" them... if you do. Thanks and sorry for switching the focus of my original question but it might be connected.

Thanks if anyone can weigh in... I'm beginning to believe the learning curve for chickens is like the horizons arc, never ending!
Thank you,
Beamerz