My 4 year old chicken is sneezing, wheezing, and has a runny nose. What's wrong with it?

[WIchickMama]

Sorry for your loss

 

[Myrshine]

There’s a wide range of different respiratory infections that can cause these symptoms, almost every one of them mimic one another. Common respiratory diseases that may be the cause are MG, Infectious Coryza or IBV. You can read more about them here —

MG/MS - https://drive.google.com/file/d/1oz-jemqYjmVj0wEUj4gAI5VQ6idPotUU/view?usp=sharing

Infectious Coryza - https://drive.google.com/file/d/1cagk7N0YbFhryLwJu2bCM1vFFO8wUNdX/view?usp=sharing

IBV - https://drive.google.com/file/d/1PvrjqAwKgZpnhLIXUkmWmIZsyk-dWwBo/view?usp=sharing

There are treatments and preventions as well as links to online labs that you can get PCR testing at for your hen.