Sick chicken, hoping for additional feedback

[rtg54]

Hello,
We have a one and a half year old hen who has diarrhea and weakness in her legs, one more than the other. We took her to the chicken vet but we live in an urban area where the vets don't treat chickens often so we were hoping for some ideas.
The vet was not able to give us a diagnosis but brought up Marek's disease. How fast does it come on and how fast does it take them down? She started limping on Wednesday and it is now Saturday morning and she can't really stand. The vet put her on Clavamox and we have been dosing her since Wednesday evening.
She is bright and alert, eating and drinking and when we take her outside (she's in a crate in the bathroom) she chases bugs even though she can't really walk now, she is also grooming herself. She looks for her friends and except for not being able to walk is acting completely healthy. From what I've read about Marek's they show signs of not feeling well. Not saying it's not, just saying it's confusing.
We are ready to euthanize but want to make sure that we're not shorting her because we're scared.

 

[azygous]

The manifestations of Marek's symptoms are vastly variable, according to what form the disease is taking and the condition of the patient's immune responses. To get a definitive diagnosis, a necropsy on the chicken's body after death would be required. Keep it in mind because knowing if you have Marek's in your flock is crucial to future flock management.

 

[Ebony Rose]

Has anybody examined her hips, legs, ankles, bottoms of feet for swelling, bruising or evidence of bumblefoot or mites? Just saying that the vet, as portrayed in this post, seemed quick to go straight to Marek's. Did anyone check her for the more mundane?

 

[Ebony Rose]

Eeep, I should have mentioned that the diarrhea didn't overly concern me at this time of year... as it's really hot HERE and chickens consume a lot more water when it's hot out, so expel more, and it can look like diarrhea... how hot is is where you are?

 

[Shadrach]

I to would start with the more optimistic outlook and check for sprains and swellings.
Sick chickens tend to go off their food, grooming, socialization etc. A chicken with an injury tends to act as normally as the injury permits.