Very good.
In the future, if you can only give 2X a day, increase your dose. Tylan has a wide dosing range of 10-40mg/kg and the dosing I gave you is for 25mg/kg, so I'd just increase to 30-35mg/kg and give 2X a day. Make sense?
As for the photos. The cecal poop is a bit muddy looking, but...
Here's some information about treating Vent Gleet.
https://www.tillysnest.com/2012/12/vent-gleet-prevention-and-treatment-html/
I'd check the hens over for lice/mites and make sure the crops are emptying overnight.
If the respiratory distress is caused by a Virus, an antibiotic will not...
Can you get a video of her actions and photos of her, her face/eyes and her poop?
Photos of the other hen that you think has Vent Gleet?
Corid will not treat Vent Gleet. Vent Gleet is a yeast or fungal infection of the Cloaca/Vent. You will need to treat with an antifungal or yeast...
More information please?
What are you trying to treat?
You mention your hen(?) is having a hard time breathing. What are her symptoms, how old is she, does she have a history of respiratory illness, is her crop emptying, does she have fluid or bloat in the abdomen, is she having a hard time...