Help, before its too late!

[chickengirls16]

Breast bone is the long, thin keel bone below the crop, see image below.
If she's very thin then something has likely been going on with her for a while. Do you know when she last laid?
You said you lost a bird to Marek's disease, do you have that confirmed in your flock?
If that is the case, then it has to be a suspect. It can kill on it's own or leave them vulnerable to other illnesses to take hold as well. Slowly wasting can be from Marek's or Lymphoid Leukosis commonly, or from simple things like not enough feeders, crop impaction, or parasites.
I've lost birds that were obviously Marek's, and others not so obvious but it's always suspect when it's not something obvious, if you have it confirmed in your flock. It has settled down in my flock and I only have occasional losses, not like it was at the beginning.
Breast bone labeled sternum in the image below, if it's very prominent that generally means low weight and poor body condition, though some breeds will be naturally leaner than others:
View attachment 4317311

View attachment 4317319

That breastbone/sternum is very sticky-outy and obvious, however she has always been very thin and flighty.flight.

Don't remember the last time she laid, but she typically lays 1-2 a month.

Pretty sure it has been mareks. We have symptoms like:
- paralyzed legs
- on side for balance
- closed, swollen eye
- won't eat or drink
If by 'confirmed' you mean necropsy, we haven't done one yet but if Sunny doesn't make it we will definitely look into it.
I'm slowly starting to think it's mareks.
We have had the WEIRDEST death rates around here-
We will have three die one month, and then for another month we have no deaths, and then the next we lose three again, it's really odd. We recently lost a roo and we dont know why but we do not think it was mareks.
First photo is the roo we lost, second is of Sunny, third is of her breastbone, which is hard to see but it's very bumped out.

 

[coach723]

With all the losses, it would be a very good idea to find out for sure what is going on. Maybe Marek's, but other things can often look a lot like Marek's and are not. So it is a really good idea to get confirmation before assuming. Marek's can be manageable, but losses will be higher. But knowing for sure makes decision making easier going forward. I used to wait longer before euthanizing in my flock, but now if that is what it looks like, I do it sooner. Rather than letting them suffer for no reason. I still lose birds to other things (that is more common now), but with time and experience you get better at recognizing the differences a bit more. Still, it's often not known for sure until necropsy. I do most of my own necropsies now, and most of the time I can figure out what was wrong just by looking. Occasionally I get a mystery, but not very often. If I were to suspect something contagious (other than Marek's) I would send them so there are labs. Any hen over the age of two is a candidate for a reproductive problem, like cancer, so those are sadly common. Anytime you have multiple unexplained losses it's a very good idea to figure out why. Sometimes it's simply random coincidence, but sometimes it can mean a virus or toxin. It can also help to keep a simple log of your birds. When one is ill listing symptoms, treatments, outcomes, dates & times, etc., feed changes, worming dates... How much detail is up to you. Over time it's easy to forget what, who, when and the log can help. It doesn't have to be complicated or time consuming, just what works for you. It also helps with hatch dates, ages (time flies and I forget how old they are otherwise- I've had some 13-14 year old birds) and who came from who if you hatch. I will also leg band some birds to help with recognizing age groups and to easily identify a bird that might have a health issue, so I can easily pick them out in the flock to monitor. I've had birds who repeatedly prolapsed, so they get banded so I can spot them every time I'm out there, for a quick check without having to catch them every time. That is very helpful if you have many birds of a breed that are hard to tell apart. My Fayoumi's all look identical (and are very hard to catch), so three age groups are banded different colors and one bird is wearing a band to keep an eye on for possible health issues.

 

[chickengirls16]

With all the losses, it would be a very good idea to find out for sure what is going on. Maybe Marek's, but other things can often look a lot like Marek's and are not. So it is a really good idea to get confirmation before assuming. Marek's can be manageable, but losses will be higher. But knowing for sure makes decision making easier going forward. I used to wait longer before euthanizing in my flock, but now if that is what it looks like, I do it sooner. Rather than letting them suffer for no reason. I still lose birds to other things (that is more common now), but with time and experience you get better at recognizing the differences a bit more. Still, it's often not known for sure until necropsy. I do most of my own necropsies now, and most of the time I can figure out what was wrong just by looking. Occasionally I get a mystery, but not very often. If I were to suspect something contagious (other than Marek's) I would send them so there are labs. Any hen over the age of two is a candidate for a reproductive problem, like cancer, so those are sadly common. Anytime you have multiple unexplained losses it's a very good idea to figure out why. Sometimes it's simply random coincidence, but sometimes it can mean a virus or toxin. It can also help to keep a simple log of your birds. When one is ill listing symptoms, treatments, outcomes, dates & times, etc., feed changes, worming dates... How much detail is up to you. Over time it's easy to forget what, who, when and the log can help. It doesn't have to be complicated or time consuming, just what works for you. It also helps with hatch dates, ages (time flies and I forget how old they are otherwise- I've had some 13-14 year old birds) and who came from who if you hatch. I will also leg band some birds to help with recognizing age groups and to easily identify a bird that might have a health issue, so I can easily pick them out in the flock to monitor. I've had birds who repeatedly prolapsed, so they get banded so I can spot them every time I'm out there, for a quick check without having to catch them every time. That is very helpful if you have many birds of a breed that are hard to tell apart. My Fayoumi's all look identical (and are very hard to catch), so three age groups are banded different colors and one bird is wearing a band to keep an eye on for possible

With all the losses, it would be a very good idea to find out for sure what is going on. Maybe Marek's, but other things can often look a lot like Marek's and are not. So it is a really good idea to get confirmation before assuming. Marek's can be manageable, but losses will be higher. But knowing for sure makes decision making easier going forward. I used to wait longer before euthanizing in my flock, but now if that is what it looks like, I do it sooner. Rather than letting them suffer for no reason. I still lose birds to other things (that is more common now), but with time and experience you get better at recognizing the differences a bit more. Still, it's often not known for sure until necropsy. I do most of my own necropsies now, and most of the time I can figure out what was wrong just by looking. Occasionally I get a mystery, but not very often. If I were to suspect something contagious (other than Marek's) I would send them so there are labs. Any hen over the age of two is a candidate for a reproductive problem, like cancer, so those are sadly common. Anytime you have multiple unexplained losses it's a very good idea to figure out why. Sometimes it's simply random coincidence, but sometimes it can mean a virus or toxin. It can also help to keep a simple log of your birds. When one is ill listing symptoms, treatments, outcomes, dates & times, etc., feed changes, worming dates... How much detail is up to you. Over time it's easy to forget what, who, when and the log can help. It doesn't have to be complicated or time consuming, just what works for you. It also helps with hatch dates, ages (time flies and I forget how old they are otherwise- I've had some 13-14 year old birds) and who came from who if you hatch. I will also leg band some birds to help with recognizing age groups and to easily identify a bird that might have a health issue, so I can easily pick them out in the flock to monitor. I've had birds who repeatedly prolapsed, so they get banded so I can spot them every time I'm out there, for a quick check without having to catch them every time. That is very helpful if you have many birds of a breed that are hard to tell apart. My Fayoumi's all look identical (and are very hard to catch), so three age groups are banded different colors and one bird is wearing a band to keep an eye on for possible health issues.

I have heard a lot about necropsy on this website. I have always kind of thought they weren't worth it, but now I think I will try. (Definitely not by myself - I'm not exactly the dissecting chickens type.)

I do keep a log on excel for my chickens - name, breed, dob, date of death, how they died, and who was broody when an who they hatched.

Thank you, you have been so helpful!