Hen gasping, chest popping, help!

[rosiehenfeathers]

My sister's serama hen is really sick. Ahe started out yesterday morning gurgling when she breathed and open mouth breathing a bit. She was given Liquamycin-200 and vetRX in the evening. But this morning she is gasping for air, chest popping (not crackling, heavy almost, twanging pops). I gave her A direct oral dose of Denagard for her size, but is there anything else we can do??

She's been sick twice before in 30 days, treated with tylan, then LA-200 both times and pulled through. But now it's not looking so good.

My sister believes she has chronic mycoplasma in the flock. From how she has lost birds in the past, but no vet confirmation

 

[Wyorp Rock]

Can you get a video of her breathing and what she sounds like?

Upload video to YouTube and provide a link.

Was the Liquamycin given by injection or orally?

Is her crop emptying?

Is this the sweet little Serama hen you posted about that was isolating herself? Any chance she was injured?
Can you gently feel all over her body to make sure there's no feeling of air trapped under the skin?

If you suspect MG, then I'd treat with Tylan is you have it. Do you have the liquid (Tylan50) or the powder that goes in water?