Nope. We can't explain it other than it wasn't infectious in origin.
Likely neurological. She could have been having strokes. She was having trouble eating without choking towards the end. Maybe she was having neurological issues affecting the use of her tongue as well.
She would not try to stand one legged. She was laying on her left side with her right leg sticking out the last week. Likely, it was not just the right leg that was involved.
She did not eat much yesterday and stopped drinking. I was holding her this morning and in a couple of minutes, she was gone.
How sad & frustrating too
It sounds so much like neurological Marek's disease. Mareck's breaks my heart & we learned it the ever-so-hard way. Yrs back we had it w/ 2 separate birds shipped to us from private breeders who didn't believe in vaccinating. Mareck's is long-lingering w/ moments of showing up-n-down weeks & then the last week rapid decline. The vet sent us home hopefully both times saying he had seen some chickens recover... but rarely.
We returned to the vet to euthanize both birds when they stopped taking nourishment. It is not a quick disease like bird flu... Mareck's is a weeks-long suffering ~ it makes me so mad w/ private breeders who play Roulette thinking AC vinegar & garlic is a holistic cure or prevention for all chicken ailments cuz they don't want to spend $$$ to vaccinate (it's not cost-effective for small flock breeders)
After experiences w/ non-vaccinating breeders we never bought birds after that unless they were Mareck's vaccinated (which is probably why those birds are more expensive to buy from private rather than hatchery).
We also practiced quarantine of new chicks/juveniles longer than a couple weeks. We'd wait 6 to 8 weeks or more before integrating & it's been a boon to do that as ailments have been caught before integration... it happened we quarantined avian leukosis shipped birds early before integration (breeder unaware of it till later).
So sorry for anyone who has to go thru non-vaccinating sources to obtain chicks/chickens cuz it really is a time bomb. One sick bird can infect a flock... doesn't mean the hardy flock will ever show symptoms but they become latent carriers & during another compromised ailment or low immunity can have Mareck's flare up.
Our Taffy was shipped in 2013 w/her sister chick unvaccinated. The chick died the 1st month but Taffy did not finally come down w/ symptoms till she was 2-1/2 yrs old & the vet had hopes but she had to eventually be put down at the vet.
2015 ~ sick Taffy
Another shipped unvaccinated bird had to be put down for Mareck's within the 1st 2 weeks we got her. The weak legs, loss of balance, falling on weak legs, the leg sticking out when sitting, so heartbreaking to remember back in time
.
2015
Chickens are such wonderful sweeties but w/ so many health challenges to be aware of. They keep us on our toes... like marriage, not to be entered into lightly
A dog that attacks your birds, will do it again, if not restrained. I take it, you don’t have much of a choice?
seems I won’t be able to build the rooster run until it stops. Gezz, the roosters will be past their idiot phase by then. 
While pouring rain yesterday ~ Neighbor across the street had an explosion in their garage & fire. 3 fire engines to break a window to put out flames w/a hose. A little overkill on the engines I think. Took 'em longer to wrap up & leave compared to how fast they got here
is better than "frosted" anything else.
. Chickens only use coops to roost, brood, or lay eggs anyway.
Oliver!
