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[Tnkcfan]

My rooster has had this sore on his comb (it is dark from Blu-Kote) for about 6 months. Started small & keeps getting bigger. And he’s lost feathers on his neck. He acts fine.

 

[Wyorp Rock]

My rooster has had this sore on his comb (it is dark from Blu-Kote) for about 6 months. Started small & keeps getting bigger. And he’s lost feathers on his neck. He acts fine. View attachment 4316467

Looks like he's being plucked and very likely the wound on the comb is being picked at too.

You may find that you need to separate him out from the hens until he heals up. I had a rooster with a sore on his comb and would just stand and let the ladies pick at the scab until it bled (hens/chickens love blood). No matter what I tried, it would not heal and I couldn't get the hens to stop.
I moved the rooster to his own space, he pitched a fit of course, then I applied a little ointment (you can use BluKote if you wish) to the comb (the hens had almost poked a hole clean through the comb!). He was ok by himself for a few weeks of healing, he just didn't like being without the girls.
Once healed they left his comb alone.

Do check for lice/mites, but the plucking/pulling of the feathers especially on that side of the neck and where the scab is, hens are doing this to him. Roosters will often allow favorites to "groom" the feathers. Likely there's 1-2hens and they are pulling the new pin feathers out and eating them.

An alternative method would be to observe which hen(s) are picking and plucking him and put Pinless Peepers on the hens until he heals up and feathers back in, then remove the Peeper and see if the bad habits have been broken.

 

[Tnkcfan]

Looks like he's being plucked and very likely the wound on the comb is being picked at too.

You may find that you need to separate him out from the hens until he heals up. I had a rooster with a sore on his comb and would just stand and let the ladies pick at the scab until it bled (hens/chickens love blood). No matter what I tried, it would not heal and I couldn't get the hens to stop.
I moved the rooster to his own space, he pitched a fit of course, then I applied a little ointment (you can use BluKote if you wish) to the comb (the hens had almost poked a hole clean through the comb!). He was ok by himself for a few weeks of healing, he just didn't like being without the girls.
Once healed they left his comb alone.

Do check for lice/mites, but the plucking/pulling of the feathers especially on that side of the neck and where the scab is, hens are doing this to him. Roosters will often allow favorites to "groom" the feathers. Likely there's 1-2hens and they are pulling the new pin feathers out and eating them.

An alternative method would be to observe which hen(s) are picking and plucking him and put Pinless Peepers on the hens until he heals up and feathers back in, then remove the Peeper and see if the bad habits have been broken.

Thank you for your reply. I had first thought it was some younger roosters picking his feathers, so I got rid of them & now he is the only roo & has been for about a month with no improvement. I spend a lot of time with them & have never seen the hens pecking him, but I have seen the spot on his comb bleeding several times, so someone is pecking it. I will try separating him & see if he improves!