It was possibly an ovarian tumor as chickens, not being mammals, don't have mammaries.
Mareks will cause tumors throughout the body. Sometimes they localize around the reproductive system. I would suspect normal cancer had the bird not experienced blindness and difficulty walking yesterday.
The only way to tell for sure what it was - herpesvirus or not - is through a histopathology. But really they're expensive and, in this case, not really relevant as marek's is very very common.
This doesn't mean, at this point, that your flock is more likely to die than any other flock with the zillion things that effect poultry. It is very hard to keep Mareks out of your flock anyway as it's highly transmittable, even being spread on the wind via dander, etc.
Many birds will carry mareks and not show symptoms - they just shed the virus. Once a yard is exposed to mareks, it's always exposed. But to prevent it being an issue simply choose vaccinated stock. Buy from places that vaccinate - make sure they vaccinate. If they don't, you can vaccinate easily as an SQ (subcutaneous = under the skin) injection at the back of the neck. The only drawback is that the vial comes in 1,000 dose vials only. It's best done to one-day old chicks. You should never vaccinate birds already exposed to mareks as they may possibly already be carriers. this means your extant flock. Just incoming birds on the very first day of their arrival if they're not exposed and not vaccinated.
This all sounds way more scary than it is. Just take the precautions and when you see signs like this, know it's something to rule out.
That doesn't mean that any wobbly or thin bird will have mareks and die from here on out. You'll never know until either a necropsy or a certain set of symptoms. So don't let it get you too paranoid. But if you get one that is doing the splits, paralyzed in one leg, or goes blind or has eye malformations - they could have Mareks.
As I believe I said earlier, I had two birds that lived into very old age with just the optical form of Mareks. I'm sure that probably more than a couple of my birds that died of old age died of Mareks. But who knows? Most of my flock died of old age or predation, two birds had one-eye blindness and were very very hardy. Any chicken anywhere could be acarrier, so I don't worry about it.
If I have babies that I hatch, I'll vaccinate to make it less likely they'll be effected.
Hope this helps. Take a deep breath. It's going to be ok.
Postscript: By the way, tumors in the reproductive tract of layers are very very common. That'll happen way more often than Mareks will in any flock, even an exposed one. Your bird's more likely to die of internal laying and other goofy things. It's only the presence of the difficulty walking and the sudden blindness that tell me this was mareks.
Mareks will cause tumors throughout the body. Sometimes they localize around the reproductive system. I would suspect normal cancer had the bird not experienced blindness and difficulty walking yesterday.
The only way to tell for sure what it was - herpesvirus or not - is through a histopathology. But really they're expensive and, in this case, not really relevant as marek's is very very common.
This doesn't mean, at this point, that your flock is more likely to die than any other flock with the zillion things that effect poultry. It is very hard to keep Mareks out of your flock anyway as it's highly transmittable, even being spread on the wind via dander, etc.
Many birds will carry mareks and not show symptoms - they just shed the virus. Once a yard is exposed to mareks, it's always exposed. But to prevent it being an issue simply choose vaccinated stock. Buy from places that vaccinate - make sure they vaccinate. If they don't, you can vaccinate easily as an SQ (subcutaneous = under the skin) injection at the back of the neck. The only drawback is that the vial comes in 1,000 dose vials only. It's best done to one-day old chicks. You should never vaccinate birds already exposed to mareks as they may possibly already be carriers. this means your extant flock. Just incoming birds on the very first day of their arrival if they're not exposed and not vaccinated.
This all sounds way more scary than it is. Just take the precautions and when you see signs like this, know it's something to rule out.
That doesn't mean that any wobbly or thin bird will have mareks and die from here on out. You'll never know until either a necropsy or a certain set of symptoms. So don't let it get you too paranoid. But if you get one that is doing the splits, paralyzed in one leg, or goes blind or has eye malformations - they could have Mareks.
As I believe I said earlier, I had two birds that lived into very old age with just the optical form of Mareks. I'm sure that probably more than a couple of my birds that died of old age died of Mareks. But who knows? Most of my flock died of old age or predation, two birds had one-eye blindness and were very very hardy. Any chicken anywhere could be acarrier, so I don't worry about it.
If I have babies that I hatch, I'll vaccinate to make it less likely they'll be effected.
Hope this helps. Take a deep breath. It's going to be ok.
Postscript: By the way, tumors in the reproductive tract of layers are very very common. That'll happen way more often than Mareks will in any flock, even an exposed one. Your bird's more likely to die of internal laying and other goofy things. It's only the presence of the difficulty walking and the sudden blindness that tell me this was mareks.
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