I have never had two roosters work out living in a pen. My free range flock on an acre have about ten hens and the roosters work together like ninjas. One was slightly older
I have 3 black lorps in North Florida but this will be first summer
They are in a Coop with a tarp on the backside so shade or sun if they prefer I guess
I'm not sure exactly what the USDA says all I can keep saying is here in the South lol. Definitely doesn't hurt anything and I strongly recommend it for any kind of illness I keep over 50 chicks and chickens and have a very very low mortality rate
The oatmeal could do nothing bad bad idk where she is located but if it's cold nights I should have stated add then as a said I would throw the kitchen sink at this until necropsy is back . Like I said before no expert i just know what I was told to so from old southern( US) farmers
The Apple cider vinegar does help with adding vitamins it is nearly constantly in my water as well as tons of other byc members , I'm not saying it will help this particular situation but a cap full definitely wouldn't hurt anything, and even old timer remedies may be all she has while awaiting...