Swollen Head Syndrome? Is it contagious?


8 Years
Feb 2, 2011
Middle GA
I have a Dominique rooster who will be a year old in December who developed a swollen face (behind his eye, only on one side) about 2-3 weeks ago. It is slowly getting bigger. He is acting perfectly normal......no other signs of illness whatsoever. The swelling isn't in his comb or wattles, and has only increased in size by a small yet noticeable amount in the past 2 weeks. At first I thought he got stung by a bee or something. But 2 weeks later and it looks like it has gotten a bit worse?

He is in a fully enclosed pen with several other hens and another rooster (they get along well, he's actually dominant.) No one is showing any signs of anything abnormal. All the other birds in there I either hatched myself or got directly from a hatchery. I have other chickens on the property, but other than a bought of cocci, everyone has been healthy. NO sneezing, rattling, bubbly eyes, bad smell, odd deaths, etc. in anybody.

Does this sound like it could be SHS, even though its only really on one side? And if so, is it contagious? What can I do to help the guy out? Like I said, it's not as bad looking as some pictures I've seen, but I don't want it to get worse. I tried to take pics, but I was by myself and they didn't turn out well.

Swollen head syndrome is rare, more in meat birds, and the swelling is over the whole head. You are probably dealing with MG, which can be treated with Tylan 50 injections or oxytetracycline in the water. Tylan 50 can be given orally also--dosage is 1 ml for over 5 lb orally for 5 days, or given as a shot 1/4 inch into the breast muscle for 3 to 5 days. MG and other respiratory can cause carriers, so you will want to close your flock, and not sell birds or hatching eggs. Eggs for eating are fine. Here is a link to read about the common respiratory diseases--MG, bronchitis, coryza, and ILT: http://edis.ifas.ufl.edu/ps044

Below is a chicken thought to have swollen head syndrome:

Last edited:
Can wild birds be carriers of MG? I know it is very common, I had a flock that had mycoplasma years ago. I was hoping to avoid it this time. :(

These birds are not (or have ever shown) any symptoms of what I dealt with before.....aside from this fella who has half a swollen head, and all swelling is behind his eye. (The birds I had before with mycoplasma didn't ever swell though, just had the bubbly eyes and sneezing.) All my current birds came in as chicks from hatcheries or eggs I hatched from NPIP breeders.

If I have this AGAIN I will be devastated. :(
I guess I could also mention that the "swelling" almost looks more like a growth. It's more isolated than spread out......like it's almost like a horn bud that is protruding, there is almost a definite "line" where it stops.
Yes, wild birds can carry most of the common respiratory diseases including MG. With a milder case of MG it is possible to just have some swelling around one eye and nothing else. Your picture will be good. Someone else recently had a similar growth that looked like a small horn coming out of the face. I'll see if I can't look it up.
So if birds can carry it, how are our flocks supposed to stay safe? :( The blue in the tip of his comb is new today. Still no other symptoms, he's eating fine.

New posts New threads Active threads

Top Bottom