Marek's Disease in Chickens: Symptoms of Manifestation and Treatment
- 20 Oct 08:45
Marek's disease in chickens, the treatment of which will be the subject of our conversation now, refers to the most common type of disease - lymphoproliferative. Of course, for many this word is not familiar. The peculiarity of the ailment is that it proceeds in three forms: occipital, in the form of tumors and neural in.Read this article.
- 1 Description
- 2 Symptoms of
- 3 Treatment Methods
- 4 Video «Principle of vaccination of chickens from Marek»
The cause of the disease Marek is a virus that is aerially transmitted. Today, scientists have learned from the chickens to create transovarian immunity, however, this does not completely control the disease.
So, the Marek virus is correctly called herpesvirus, as it is associated with the defeat of the cells of the body. Its properties of influence are similar to the properties of gamma-herpesvirus and are designated as serotype 1 and neonicogenic strains of serotype 2. Chickens are just the carriers of these some strains, which is why it is they who so often have a disease. For the first time, the name of Marek was diagnosed with illness in 1961 in order to make a clear distinction between other lymphoproliferative diseases. Prior to the invention, the virus was a huge threat to the production of chickens.
However, even a vaccine is not always a guarantee that poultry does not suffer from this disease. True, the virus ceased to represent a threat to the economy, although many birds die from it. Today, Marek's disease of chickens is common in all countries of the world.
Symptoms of the manifestation of
The main symptom of Marek's disease is a limb paralysis. Which part of the body will be paralyzed, or all the limbs depend only on which nerve or somewhat damaging the virus. The incubation period depends on the age of the bird and may range from 2 to 15 weeks.
Due to the infection in the bird, there is a tendency to movement, weakness, followed by complete paralysis of the wings, paws, goiter, neck, etc. With such damage, mortality occurs in 10%.But if the paralysis affects the nerves of the internal organs, for example, the stomach and leads to its atrophy, the bird dies quickly. In adults, Marek is often a symptom of deformity of the pupil and iris.
The first sign of the disease may be the restless movement of the chicken, its unnatural stroke, and also the posture where one paw is extended forward and the other is back. In case of mass infection in the hens, severe depression, paralysis, depletion and dehydration of the body develops. After that, as a rule, birds die. They also instantly slip away with eye damage.
It is important for owners of hens to remember that the younger the bird and the higher the genetic potential of the breed, the more it is prone to Marek's disease. Today, it is also distinguished by its classic shape and sharpness. In classical birds, the
- nerve syndrome may appear;
- eye damage;
- Neck twist;
- is a semi paralysis.
In this form, chickens die in 30% of cases, to a greater extent in the treatment, the disease passes and the bird heals.
The most important rule for Marek's disease is the age-old vaccination. This is the only and correct prevention of further illness. In some cases, the chickens can be vaccinated again - between 10 and 21 days from birth.
Today the poultry farms use the following vaccines:
- Virus vaccine is liquid culture;
- Nobilis Rismavac and Nobilis vaccine;
- Bivalent Cultural Virus Vaccine.
Treatment is difficult and possible only in the early stages. If paralysis occurs, usually a complete recovery does not occur.