Can 9 month old vaccinated pullets bring Marek into my flock?

[BDutch]

I personally do not bring in chickens from outside my flock due to the unknowns of what they might be exposed to at their previous location. Mareks is pretty much everywhere in the world, but I would rather start with healthy chicks from a hatchery for the best chances. Unfortunately, that limits some of the rarer breeds.

Here in the Netherlands it’s easier to buy hatchery eggs from hobbyists. It’s not allowed to send chicks by mail.

The commercial hatcheries who sell bantams don’t sell hatchery eggs. They prefer to sell POL chickens.

I like to give my Dutch a 6 pack fertilised eggs to hatch if they are broody . And its always nice to have contact / see the setups of the breeders. The prices for the eggs are nice too. They vary from € 1 - € 2 for most breeds.

The only con is that I have to give away all cockerels.

 

[BDutch]

I remember that we have a trustworthy animal site in the Netherlands.
It has a good explanation on Mareks disease. No time now to translate it now. But Google translate or chatGtp can help everyone who is interested.
https://www.levendehave.nl/dierenwikis/pluimvee/ziekte-van-marek

 

[BDutch]

Video from the article and ..
The translated article from levende have wich means living lifestock.

Spoiler: Marek’s disease

Marek's disease is a common condition in chickens and turkeys. It is a viral infection, which causes tumor formation in the nerve tissue. The symptoms can vary quite a bit, because the place where the virus settles in the nervous system can also be very different.

In Marek's disease, leg palsy often occur, because the problem occurs in the nerves that run to the chicken's legs. Sometimes one leg is done, sometimes both. The animal drags on or can no longer walk at all. Other nerve tissue can also be affected, for example the optic nerve, so that the animals become blind on one side or at both eyes. The tumors can also strike in one or more organs, which can cause acute mortality at the age of about three months. An enlargement of the head can also occur in Marekse Disease. The head has been paralyzed by damage to the head nerves.

By performing the so-called 'stret reflex', it can be determined whether the nerves are affected. Lift the chicken at the wing base and make a quick 'fall movement' from about one meter height. Healthy chickens will then stretch both legs. Animals with Marek's disease lack this reflex, on one or both legs.

Marek's disease is a highly contagious disease, which is seen in young chickens aged three to five months. The infection does not cross from mother to young through the egg, but occurs through dandrogs and feather particles of the older animals that can form a permanent source of infection. Chicks are infected at a very young age. Infection in old age also occurs, but that has much less consequences for the infected chicks. It takes a few weeks for the infection in the young chicks to develop sufficiently and the first victims become visible. Especially the varieties Sebright and Barnevelder and to a lesser extent also the Brahmas are sensitive to the disease.

Diagnosis

The diagnosis can be made on the basis of the clinical picture and by experts via section of sick or deceased animals. The abnormalities in the nerves are visible to the naked eye or via microscopic examination. Turning necks, falling over, lowering through the legs, curvature of the toes and leaving the head hanging are the most eye-catching phenomena. In the acute form, the lis and legs become paler. The animal also thins quickly.

The infection can take decent forms, that is, many animals are affected and the symptoms come back in each subsequent couple of chicks. Some animals survive and can permanently transmit the infection. There is no therapy. Marek's disease is a viral infection and by definition there is no treatment for it.

If you have a chick with Marek's disease, there is a good chance that more victims will fall. It's always good to inform the person from whom you bought the chicks. It's best not to add new chicks now and take a look at it. When all the chicks have died, you should clean and sanitise the chicken coop well with a remedy that also kills viruses. Like Virkon S.

Prevention of Marek's disease

Prevention is possible. One could breed chicks separated from older animals in a disinfected room, or in a room where poultry has not been housed before. The infection goes from older to younger animals and an absolute separation between these groups could offer a solution. This is of course difficult to do for hobby animal owners with whom the chickens raise their own chicks. But if there are chickens that have been vaccinated in the past, that is wise. These chickens can still carry the virus with them. It also often happens to chickens from the industry that they are poorly vaccinated, so that they can later get Marek's disease. If you can't rule out Marek's Disease, set the chicks aside immediately after they come out of the egg.

In professional poultry farming, a prevention method has been sought through vaccination. It was also found. Because different virus strains occur, a milder form has been used to prepare a vaccine. It also works, but vaccination remains difficult for hobby animal owners to do. Because the infection can occur shortly after birth, rapid intervention is necessary. Immediately after birth, the chicks can be vaccinated, but that must be done accurately. The vaccine is 'freezed', that is, delivered in powder form. It should be prepared and then applied immediately. The effectiveness disappears quickly (within a day). Every animal must also get enough vaccine, otherwise it won't work yet. Care with that little chick is therefore required.

What to do if you never vaccinate against Marek, but suddenly get chicks that have been vaccinated? Then there is a small risk: these chicks can excrete a limited amount of virus. Whether that's enough to get your unvaccinated chickens into trouble, you have to wait and see. Older chickens won't get sick anytime soon.

Bulk packaging

The problem for hobby animal owners is now that the graf is only available in bulk packs (1000 doses). Vaccination of some animals is therefore almost impossible, unless one is willing to destroy the other vaccine. A solution can be found in hatching eggs in a common incubator. Hobby animal owners can jointly incubate a much larger number of eggs at the same time. The chicks, which then hatch approximately simultaneously, can be vaccinated by the veterinarian at the same time. Another possibility is to contact a professional chick brother, who may be willing to give up a number of doses of vaccine. The eggs must then hatch on the same day as the chick brother's. In short, a difficult problem that turns out to be solvable with some creativity and perseverance.

If you want to vaccinate your chicks against Marek's disease, contact your veterinarian or a poultry club near you.

Not everyone is in favor of vaccinating. Opponents warn: once vaccinating is always vaccinating. The virus can also return in vaccinated animals. According to them, it is better to breed only with animals that have no predisposition to the disease.