Necropsies

[farm_mom]

Thank you maineiac and MNKris for all the great information. I really appreciate you sharing what you've discovered, and the hope that comes with it. We haven't lost any chicks since the third day, and while I do have a few showing leg problems now, there are still some acting normal and healthy. I was really hoping that I could still end up with a breedable flock, and not have to cull the survivors as the literature recommends, so thank you for the hope.

 

[coopist]

MNKris, do I understand correctly that he was hypothesizing that the breeder vaccinated for AE, but that the AE vaccine was bad? This seems logical. I didn't know that breeders routinely vacc. for AE. But that's interesting.

As to culling, I'd wonder about the carrier status. Sure, they'll be immune if they recover, but could they then shed virus and infect an adult with no immunity, who might not show disease (symptoms subclinical) but lay eggs that would hatch sick chicks? For instance, in my flock, I have many adults that I raised myself from chicks, and they've never been vacc. for anything. If they were put in with recovered adolescents, I'd wonder about their risk. I'm not making a statement on this one, I'm just offering a thought...For me, it would depend on whether or not I could keep these birds separate from potentially vulnerable older birds...

This all seems like a lot of information for you guys to wade through. And I think even those of us who aren't dealing with the problem should be grateful for your efforts, because it could happen to us in the future. I have an order in with a breeder farm in the same state, not MM but in Iowa, and this is all good to know...

 

[farm_mom]

coopist-I read this in The chicken Health Handbook "An adult outbreak is so mild it is likely to go unnoticed, lasts less than a month, and leaves birds immune w/o making them carriers."

 

[carousel]

In not a vet nor do I play one on TV <G>
and again IF B I G if some of us have AE

I would expect that once the chick recovers it should not be a "carrier" and shedding virus. (I need to know that time frame)
no more than than I am a speader of chicken pox, or the flu or the cold once I have recovered.

Just like puppies that survive Parvo - they are immune for life but are not spreading Parvo to other puppies once they stop shedding virus.

But it just depends on the behavior of the Virus - Herpes Virus for example is often shed in times of stress etc (Mareks is a Herpes virus frrom what I understand)

I got 3 of my friends chicks last night (we have a total of 5 affected chicks) that are having problems (our order that we split up between 2 houses), 2 of them have more observable symptoms than my 2. I think I'm going to take the 3 worst to the vet today. And the vet will then proceed to decide who is the best choice for a necropsy and if we need to do anything with the other 2. The other 2 in the hospital brooder are almost back to normal? we are going to give them a chance. both are flying to the edge of brooder when I change water and scratching around.

I will share what I learn from the vet as I learn it.
CS

 

[MNKris]

Quote:
All the information I discussed with the vet is completely informational at this point, based on what illness I described in the birds and the fact that one result already came back as AE from another source. The final tests have not been completed yet. He in no way was hypothesizing anything regarding a bad vaccine. He just said it was conceivable and I thought it was a good point and something I had not thought of previously. I was firing 10 million questions at him and of course, any discussion is purely speculative. I suppose, like you and me, he doesn't know what the specifics of the hatchery's vaccination policies/programs are for their resident flocks. It is however, standard industry policy for breeder flocks to be vaccinated for this particular disease.

Regarding Older Birds...I asked the very same questions, because I started thinking about my Marans, and I am still a little confused about it. If I am understanding him correctly, and again, I am not a vet and this is pretty new stuff for me, but I believe he said no, that's the beauty of the disease, if there is one. Older birds can get exposed, but are able to produce the antibodies necessary to fight the virus and normally they are asymptomatic (show no signs). From what I read, a typical sign would be a decrease in egg production if anything at all. They in turn pass these good antibodies onto their offspring. It is kind of confusing to me because I was like, "OK, then how did our chicks get sick in the first place being older exposed birds are supposed to become immune and pass on that immunity?" But if I am thinking this through correctly, there is a window where infected adult birds don't have the antibodies to pass on, and that window is where you get the vulnerable/sick chicks.

Because there has been so much info in the last few days flowing through my feeble brain, I am going to let him answer these questions for sure after our results are back. Again, I would keep these chicks separated out.

 

[fleenorfarmmom]

Thanks MNKris.That is the most helpful info so far. I have 3 Speckled Sussex that I am nursing along, along with 1 cochin and a polish with a crooked beak that just needs the tlc. They were all together to start with and all 50 of the others seem fine. We have moved some of the chicks to the chickenhouse and all seem ok out there. Keeping fingers crossed. This has been such a mess. I just HATE it for the babies.

 

[coopist]

Quote:
Okay, I see. Of course he is merely offering distant speculation at this point. I should have phrased differently. Still interesting though.

Yeah, I'm thinking similarly about that "window." Otherwise, how would the virus be transferred laterally to a hen who has subclinical infection, and thus lays infected eggs? From chick to chick, sure, but there must be adult lateral transmission too, yes?

And of course, carousel, it would depend on the behavior of the virus. But, as you rightly point out with herpes, some infections recur during stress. I have no idea how avian picornaviruses behave. But I'm looking forward to learning more about this.

 

[dlhunicorn]

...with great sadness I have read about these chicks...so very sorry for all having to deal with it.
In addition to the excellent information given here, I am posting some info which I hope will help those looking (((hugs to you all))) :
http://www.spc.int/rahs/Manual/AVIAN/AVENCEPHALITISE.htm
Nature of the disease
Avian encephalomyelitis (AE) is a viral disease of young chickens caused by a virus from the Hepatovirus family and characterised by central nervous system signs (Epidemic Tremors). It can be the cause of significant economic loss.
Classification
FAO List C disease
Susceptible species
AE occurs naturally in chickens, turkeys, pheasants and Japanese quail.
Distribution
AE has been reported from virtually all developed countries, including New Zealand, Australia, USA and New Caledonia.
Clinical signs
Chickens of all ages are susceptible, but clinical signs of encephalitis only develop in those younger than four weeks. The disease is similar in turkeys and chickens. Under field conditions disease is most common in the 1–2 week age group. Following initial dull expression of the eyes, the following signs are seen:
- progressive ataxia with the chick losing control of legs, sitting on its haunches and falling onto its side;

- tremor of the head and neck.

Ataxia progresses to paralysis and death results from inability to feed or drink, or through being trampled.

Some birds recover, and others may survive with persistent clinical signs.

In susceptible adult birds, infection is usually sub-clinical, although there may be a transient drop in egg production.

Post-mortem findings
In chicks dying of AE there are no characteristic gross lesions. Histological examination of brain and spinal cord reveals characteristic encephalomyelitis with neuronal degeneration, perivascular cuffing and gliosis.

Differential diagnosis
Newcastle disease
St Louis encephalitis
ricketsiosis
vitamin E deficiency
vitamin A deficiency
riboflavin deficiency
perosis

Specimens required for diagnosis
Samples of brain tissue should be collected for histopathology, fluorescent antibody testing and/or virus isolation.
Serum sample from young chicks should be collected for ELISA test.

Transmission
AE virus is transmitted both vertically and horizontally i.e. through the egg and by contact. Eggs laid by hens with sub-clinical infection will carry the virus. While hatchability drops, eggs will hatch and chicks will develop clinical disease soon after. Affected chicks shed virus in faeces and will infect susceptible in-contact chicks.
To date wild birds have not been incriminated as reservoirs.

Risk of introduction
AE could be introduced through the import of sub-clinically infected adult breeding stock, infected day-old chicks or hatching eggs.
Control / vaccines
Immunisation with unattenuated live virus or with inactivated vaccine has been successfully used to control AE in both chickens and turkeys. If live king water. Breeder chickens are vaccinated at 10-16 weeks of age. Pheasants are vaccinated at 5-10 weeks of age and bobwhite quail at 6-10 weeks of age virus is administered to breeding pullets before they come into lay, their progeny will be protected by maternal antibody.
The disease can be eliminated from flocks by immunisation, but sometimes recurs after several years of freedom.

References
Epidemic Tremor, In Merck Veterinary Manual, National Publishing Inc. Eight ed, 1998, Philadelphia, p 1971
Office International des Epizooties, 2002

http://www.idexx.com/production/poultry/poultry5.jsp
FlockChek* Avian Encephalomyelitis Antibody Test Kit
Availability/Distribution: Worldwide
The FlockChek Avian Encephalomyelitis Antibody Test Kit is an enzyme-linked immunosorbent assay (ELISA) designed to detect antibody to avian encephalomyelitis viruses (AE) in chicken serum.

http://www.lahinternational.com/pdf/AETechnicalBulletin_w.pdf
Technical bulletin (pdf) over the vaccine

 

[RedTailRanch]

Hey Everyone! Until we know for sure what we have going on here, I would like to keep looking for other things that might be the cause.

I read on another thread (a few, actually) where giving electrolytes (such as in quick chick) can sometimes do more harm than good! I posted a new topic on the subject, but wanted to respond here as well, in case more people read this thread.

There was a woman a few months ago who had a silkie exhibiting the same symptoms that some of us have. Another member warned her about the elctrolytes and she took her silkie off of them. She said she saw an improvement in the bird and it started standing and walking better.

Of course, there is no scientific evidence that the electrolytes were causing any problems, but it certainly is worth a try! I was under the impression that I was supposed to use the quick chick until it was gone!

Instead, I am going to look into a plain vitamin supplement. In the meantime, I changed out their water and did NOT add the quick chick to it. I also was not sure if using kitchen tap water, which goes through my water softener, was a good idea, so I've used water from an outdoor faucet. It may sound over the top, but I'll try anything to keep these little guys from suffering.

I would be interested to know how many people with chick problems have been using electrolytes...

 

[ChicknThief]

Quote:

I could not have said that better Terrie.


That said, has the OP udated?