I am sorry that she didn't make it. Marek's Disease is a likely cause as she is at the prime age to exhibit symptoms and silkies are particularly prone to it. Sadly it is a very common disease of adolescent chickens that varies enormously in how it presents. Infection with the virus will have occurred at least 3 weeks prior to the symptoms appearing. The mode of transmission is to inhale dander dust from an infected bird. The virus then establishes itself and lies dormant until a stressor or a weakened immune system triggers an outbreak. Some birds do recover from an outbreak but will be prone to further ones at some point in the future. Others sadly die. The ones that survive will be carriers for life but often you cannot tell unless a bird is having an outbreak, in the same way as the herpes virus lies dormant in people for weeks, months or years until something triggers an outbreak. In fact Marek's disease is caused by a Herpes virus too.
There is currently no recognised treatment although supporting the immune system with a good vitamin supplement and good food and fermented feed or a probiotic to support the digestive tract can be beneficial in helping the bird to fight it. I also find sunshine and grass have a positive effect and the company of other chickens although you have to weigh up the risks..... most will have been exposed to the virus before you were even aware it was in the flock, so I don't personally isolate Marek's sick birds other than in a cage to prevent bullying, because they tend to get depressed when they are isolated and then they lose the will to live and fight the disease. It sounds like your young bird may have had a secondary infection of the respiratory tract from the way you describe it throwing it's head back and making a choking sound. Secondary infections are common with Marek's birds because it compromises the immune system as well as the more straightforward paralysis or contortion. It may also be that there was a tumour in the lungs as visceral tumours are usually the final stage of Marek's.
A necropsy would be necessary to confirm Marek's or in fact identify any cause of death. State Agricultural depts. have diagnostic labs that can perform such testing and are often subsidised for chickens, so sometimes not too expensive. The dead bird needs to be refrigerated and sent off asap if you intend to take that route.
it was FAST. She was fine last night, eating, chasing the other girls away from the food. And gone by noon today. I’m thinking it was something more serious than wry neck, but don’t even know where to start to find out what, or if she should be concerned for the rest of her flock.
