Author Topic: Vision problems in chickens ? Mareks (Read 3197 times)

TyIsa · « **on:** July 20, 2021, 02:40:26 pm »

I have 2 chickens that have recently developed vision problems. They are ex commercial dark egg laying Marans type hens and I've had them a year so I suppose they are coming up to 3 years old.
One hen is very slow and does a head flicking movement that makes me think Marek's but surely an ex commercial bird would have been vaccinated against this? She first become ill while broody but she managed to successfully raise her chicks and these are now 12 weeks old. Her eyes look normal to me but her vision is definitely deteriorating. I did a faecal egg count when she first became unwell which didn't show anything accept coccids and as there are no symptoms of coccidiosis in her or the rest of the flock I don't think that is the issue.
The second hen has visibly cloudy eyes and often stands with eyes closed. Other than that she lays, eats and gets about normally. The rest of the flock of 15 chickens of various breeds and ages all seem very healthy.
Really thinking I will have to euthanase these 2 girls but I'm so reluctant as they are managing to eat and even lay. If it is Marek's - what does this mean for the rest of my flock?

twizzel · « **Reply #1 on:** July 20, 2021, 03:14:02 pm »

Could be mycoplasma ? My only experience of mareks was it killed a bunch of pullets I bought in, they all went off their legs.

TyIsa · « **Reply #2 on:** July 20, 2021, 03:36:32 pm »

Just looked up mycoplasma - I think they'd have discharge from their eyes. Your description of Mareks sounds typical - young birds, leg paralysis. Mine are slow and do funny head movements but not paralysed.

chrismahon · « **Reply #3 on:** July 20, 2021, 04:44:52 pm »

Most likely to be a breeding problem I think. They are only bred to last 18 months, so any future problems haven't been eliminated. I'd certainly not breed from them any only pts if they actually can't live a life anymore. That's very sad as we have two Marans (from France) that are perfectly healthy, laying and are coming up to 5 years old. Must be in-breeding in the UK and my guess is trying to make money by breeding from pullets- disgraceful!!!

TyIsa · « **Reply #4 on:** July 20, 2021, 04:58:53 pm »

I'm inclined to agree it's likely a genetic issue - i had hoped for better from these birds as they are so different from your typical ex commercial Warren type. Who's ever heard of commercial hens going broody?! Such a shame as they're beautiful birds laying really dark brown eggs.

twizzel · « **Reply #5 on:** July 20, 2021, 09:03:26 pm »

Quote from: TyIsa on July 20, 2021, 04:58:53 pm

I'm inclined to agree it's likely a genetic issue - i had hoped for better from these birds as they are so different from your typical ex commercial Warren type. Who's ever heard of commercial hens going broody?! Such a shame as they're beautiful birds laying really dark brown eggs.

I had a couple go broody once, they hatched out a few chicks each

SallyintNorth · « **Reply #6 on:** July 20, 2021, 10:44:29 pm »

Quote from: TyIsa on July 20, 2021, 04:58:53 pm

Who's ever heard of commercial hens going broody?!

Everyone who has ever had any kept naturally

TyIsa · « **Reply #7 on:** July 22, 2021, 04:08:57 pm »

Thanks Scarlet dragon, that's really interesting. I notice on the local Facebook chicken forums here people are very quick to 'diagnose' Marek's without much evidence.
I know you are not supposed to mix vaccinated and unvaccinated chickens because of the risk of the vaccinated birds being asymptomatic carriers of Marek's, however this is something I have done without problems for many years (always have a few hybrids and ex batts amongst my home hatched stock). If it is Mareks in these two, it has not affected any of the others so I assume they must have good natural immunity.