HUGE bumb on beak

[cravenchicken]

I got these 4 chickens a few months ago.I hate to say this but i dont really know much about chickens.They started getting sick a few weeks ago i really didnt think much of it figured it would just go away a week later they didnt get better so i went to the feed store told them and they gave me some antibiotics for the girls.Now one has a huge bumb almost looks like a puss blister or blood filled.What is on my chicken it looks crazy...

 

[TaLani]

So the bump isn't part of the comb on the top of its head? Maybe one of the others pecked at its head and it is a blood blister. Would you be able to post a pic?? Otherwise

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