I should have elaborated on our situation and explained that she came from a reputable breeder and was vaccinated. My neighbor bought her with 2 other Whiting True Blues and found her lying on the floor of the barn a few days later. Our immediate thought was that she had fallen from the perch but because there were no visible or palpable injuries we weren’t sure. Obviously there was compression on the sciatic nerve causing the paralysis but no other symptoms. We did daily physical therapy and made her a sling and memory foam bed but figured at some point she would have to be euthanized. Meanwhile I contacted the breeder who was adamant that she had never had a case of Marek’s among her birds in 20 years.
I’ve raised hundreds of chickens myself over the last 20 years and have never seen a case either, but I’m 99% confident our bird doesn’t have it based on her history, situation, recovery and lack of other symptoms.
The OP’s chick at 4.5 months is on the outside cusp of the most vulnerable age, which of course means nothing since a chicken can be infected at any age. Fingers crossed.
