Upper respiratory infection??

[casportpony]

Would I freeze them if I cull him.?

Refrigerate, do *not* freeze.
https://www.backyardchickens.com/t/799747/how-to-send-a-bird-for-a-necropsy-pictures

 

[Eggcessive]

Here are some links as well for finding your state vet or poultry lab to contact:
http://www.usaha.org/Portals/6/StateAnimalHealthOfficials.pdf
http://www.metzerfarms.com/PoultryLabs.cfm

 

[jaybud]

Just went thru the same crap with my flock. I gave tylan 50 injections once a day with 1cc and but vet rx antibiotic solution in the water once a day. Cured them in about 1 week.