What breed is this rooster?

[Gray Farms]

Brown Leghorn

 

[LilJoe]

Dark brown Leghorn (not light brown)

 

[chickendreams24]

Unless you're certain you have cocci in your local soil I'd skip the medicated feed and feed him a high protein flock raiser or even a grower if he's as underweight as you say.

Personally we don't feed medicated feed we just give a preventative dose of corid after about a week or so on ground.

 

[drumstick diva]

brown leghorn

 

[TexasSam]

Leghorn

 

[ThenNotSoChickenMaster]

Alright thanks guys! I separated him, and is doing great. I appreciate all the help.