Newcastle disease in chickens: description and forms, symptoms and treatment of pseudo-plague, signs

Breeding birds is labor intensive. Birds often succumb to various infections, viruses. One of the severe pathologies is Newcastle disease in domestic chickens.

To prevent the development of the disease, to save the livestock, you should familiarize yourself with its features.

What is Newcastle disease?

Newcastle disease is an acute, highly contagious disease of birds, caused by viruses, phenomena of hemorrhagic diathesis. The gastrointestinal tract, respiratory tract and central nervous system are affected. Waterfowl are not susceptible to pathology.

Death occurs in 80% of cases. Possible spread of the virus to nearby households, people.

Disease forms

Newcastle disease is acute, the clinical picture is easily recognized. There are 4 forms of the pathological process, which differ in the intensity of symptoms, the scale of damage. Young chickens are more at risk.

Beach Shape

Acute form of infection of viral etiology, entails the death of almost all chickens. Symptoms include coughing and trouble breathing. The conjunctiva of the eye becomes inflamed.

Doyle uniform

The form of Newcastle Doyle's disease is experienced most severely by birds, they lose their appetite, muscle spasms appear, weakness, accumulations of mucus in the nasal passages. Chickens often go blind, paralysis of the limbs occurs.

Form Bodette

Compared to the previous forms, this one is lighter. With successful treatment, 2/3 of the population is saved. Young chickens suffer the disease more severely than adults, often dying after severe damage to the central nervous system. The mold is used to make a live vaccine.

Hitchner Shape

Easiest form - Hitchner, birds lose their appetite, become weak, overall performance drops. Due to its low virulence, the variety is used to create most of the vaccines. Fatality is rare.

Is Newcastle disease dangerous for people

Adults are not threatened by Newcastle pathology, but infection is possible when interacting with a sick bird, since the virus is transmitted by airborne droplets. You can also get infected by rubbing your eyes with dirty hands.The incubation phase for humans lasts 1 week. Symptoms are similar to the first manifestations of the flu. Hyperthermia, runny nose, general weakness in the body begins. In more rare cases, diarrhea, conjunctivitis occurs.

Prevention includes washing hands thoroughly after working in the chicken coop, not eating raw eggs, wearing a mask when vaccinating.

The virus is dangerous for children, but such cases are rare. In its severe form, Newcastle disease causes brain damage.

Causes of occurrence

The sources of Newcastle disease pathogens include infections. 2 days after infection and a day before the onset of symptoms, the virus is released during breathing and coughing, with expiration from the oral cavity, feces, eggs.

Among the possible causes of Newcastle disease are the following circumstances:

not maintaining sanitation in the chicken coop;
lack of bird vaccination;
contact of domestic individuals with wild birds, no distinction in the form of a poultry house.

Carriers of pathogenic agents can be passive-immune chickens infected from birth, and adults with low protective properties.

Signs and symptoms of Newcastle disease

In chickens, the incubation period lasts 3-6 days, the symptoms are varied, depending on the form of the pathology and the stage of its development.

The main manifestations of Newcastle disease include:

feed refusal;
decrease in activity;
lack of response to sounds;
hyperthermia up to 44 degrees;
conjunctivitis and cloudy eyes;
increased goiter, excretion of fetid exudate from the beak;
diarrhea of a green tint with mucous impurities, sometimes bloody streaks;
breathing problems - beak open, chickens coughing, sneezing, stretching their neck, wheezing.

In an acute course, birds die in 2 days. When the nervous system is damaged, coordination is disturbed, chickens walk in circles, tremors, convulsions, paralysis of the wings, twisting of the neck are noted. Death occurs in 3-12 days.

When a bird recovers, it remains a source of infection for 2-4 months. It is necessary to isolate cured individuals from he althy chickens for this period.

Diagnosis of disease

To establish a diagnosis, you need the results of clinical and post-mortem studies using laboratory tests.The spread of infectious agents to nearby territories is also taken into account. A veterinarian is called to the site, it is impossible to independently establish a verdict based on symptoms.

How pathology is treated

There is no therapeutic regimen for Newcastle disease. The poultry farmer should only stop the spread of the virus. The following complex of manipulations is being carried out.

All excrement is removed from the chicken coop, burned.
The room is treated with caustic soda, formalin solution, carbolic acid and alcohol.
Sick individuals are killed, cremated.

After processing, the chicken coop is closed. When the quarantine is completed, the premises are chemically treated. Sometimes a veterinarian will prescribe antibiotics given to isolated, sick chickens. The success of therapy is doubtful, depending on the stage, form of the pathological process.

It is forbidden to hold such events:

take out birds, their eggs;
sell the meat of a dead bird, its down and feathers.

It is necessary to close access to the territory to unauthorized people.

Possible consequences

If left untreated, the livestock dies, the virus spreads to nearby birds. Children can become infected, the well-being of adults will worsen. When new chickens are brought into the house, they also become infected with the virus because the house is not treated.

Prevention of occurrence

In poultry farms, chickens are vaccinated. Chicken coops are disinfected about 2 times a year. Newcastle disease virus susceptible to sodium hydroxide solution 2%, bleach 3%.

Cleanliness

The poultry house should be cleaned once a week. It is important to take away all the feces, fallen feathers, and burn them.

Decontamination

The poultry house should be periodically disinfected with ultraviolet rays, lamps should be installed in it. Still resort to quartz. Decontamination should be done once every 2 weeks.

Quarantine

The poultry farm is closed for quarantine for a period of 1 month. Notify the local authorities, veterinary service, supplier farms and partners about the viral infection of the livestock. Poultry farms enclose, close access to third parties. The supply of birds is suspended, trade is stopped. Sick individuals are destroyed by strangulation, a bloodless method is required. To prevent the spread of viral agents during the killing of birds, close all windows, doors, hoods.

Corpses are burned in 0-deep pits.7 meters or ovens. The inventory and the place of burial are disinfected. He althy individuals are kept in isolation, vaccinated. Before the end of the quarantine, the poultry house is disinfected. Metal equipment is not resistant to bleach and alkali. Their processing is carried out with formalin, wet or aerosol. When a mass death of birds occurs from Newcastle disease, quarantine is established for 5 days. During this time, they destroy all individuals, make a complete disinfection dangerous by contamination of the territory.

Chicken vaccination

Chickens are immunized with vaccines based on live or inactivated viral strains. The choice of the drug depends on the age of the bird, the well-being of the area, the direction of the farm.

There are such features of different types of vaccinations:

inactivated - manipulation is carried out when chickens reach the age of 120 days, the duration of immunity protection is 6-12 months;
live - weakened viral agents are used in pathologically disadvantaged areas - the North of the Caucasus, the South, preparations are prepared from the strain La-Sota or Bor-74.

After being vaccinated, birds develop antibodies within 3 months. Mostly vaccinate young chickens at 15 days. Young growth of egg breeds are vaccinated again from 2 months. The effectiveness of the formation of the immune response is due to the conditions of keeping and the quality of nutrition of chickens, the method of vaccination.