Symptoms and treatment of bird flu in chickens, signs and manifestations

Symptoms of bird flu in chickens frighten all owners of farms or private estates. The disease is extremely dangerous; it has another name – “classical plague”, due to its high mortality rate. The pathology is fraught with large losses, and human infection is possible. To safely prevent it, you should read the information below.

Description of the disease

The first mention of bird flu dates back to 1878. The pathological process was discovered by a veterinarian from Italy named Peroncitto. Due to the massive death of livestock, it was originally called “chicken plague.” The disease belongs to subtype A and is caused by viral microorganisms. Not only poultry, but also humans are affected. Chicken flu usually develops in winter, affecting one bird population, then the rest.

Ducks, geese, and chickens are at risk. Influenza is especially dangerous because it constantly mutates and prevents a person’s protective properties from fighting it. Since the virus is virulent, transmission occurs through airborne droplets.

Stages of the disease

Once in chicken lungs, viral agents spread throughout the mucous membrane. After 4 hours they penetrate into the general bloodstream, destroy red blood cells, causing death. Viral microorganisms affect the nervous system, after which the lungs swell and the intestines fail.

What are the stages of the pathological process of viral etiology:

• infection, further reproduction and accumulation of the virus in the body;
• spread of viral agents to red blood cells;
• the body's production of antibodies to resist viruses;
• the struggle of protective functions with pathology, destruction of blood cells;
• The body cannot cope with the virus and dies.

From 10% to 100% of birds kept in one territory die.

Forms of "chicken plague"

There are several forms of the viral disease. If we are talking about a severe phase, then for the first 15 hours of infection a clinical picture appears.

What are the forms of influenza disease:

• acute – the most life-threatening for birds, the symptoms are pronounced;
• subacute phase – less dangerous for birds, lasts about 1 month, treatable;
• chronic form - the disease is difficult to identify, the clinical picture is mild, infection develops due to a low pathogenic strain.

The incubation period lasts about 4-5 days.

Is it possible for humans to become infected?

A person can get sick with “chicken distemper” through airborne infection. This happens when cutting carcasses, assembling and packaging eggs and meat. Viral agents also enter the body when removing excrement or touching contaminated objects.

Infection rarely occurs after consumption of meat or eggs from affected individuals. Influenza is mutational and often changing in nature. Healthy people can become infected with bird flu from a sick person.

Causes of occurrence in birds

Influenza disease is provoked by the Ortomyxoviridae virus, which belongs to group A. It has a complex structure, the microorganism is capable of being resistant to medicinal drugs.

Scientists studied several varieties of the virus, but they were more interested in the H7N7 type, which causes avian plague, and the H5N1 virus, which kills birds within a day. Other types of viral agents can be asymptomatic or mild; they are usually not dangerous.

In addition to animals, carriers of pathogenic microorganisms can be:

• duck eggs;
• chicken eggs;
• carcasses of infected birds.

The deadly H5N1 virus is also dangerous because it is invisible and easily adapts to the environment. Methods for its destruction have not yet been developed. The main carriers of influenza include wild waterfowl and migratory birds. They do not experience widespread diseases; usually only a few individuals get sick. The pathology occurs without symptoms, but they can infect domestic birds or people. The second group of virus carriers includes exotic birds, for example, parrots.Chickens can become infected from them if the owner of the house keeps these pets.

Clinical picture

The disease manifests itself with varying intensity, depending on the stage. The main symptoms of “chicken plague” include:

• a sharp decrease in egg production;
• exhaustion, complete refusal to eat or drink;
• feathers are very ruffled;
• the birds wheeze, their breathing is gusty;
• the temperature rises, it can reach 40-44 degrees;
• there is stool disorder, the droppings are brown with a green tint;
• Convulsive muscle contractions and neurotic behavior begin.

First of all, the nervous system is affected, the chickens cease to navigate in space. They stagger, are unable to stand on their feet, and fall.

The wings and neck are deformed, they acquire a non-standard position, and there is no reaction to external stimuli. The birds suffer from thirst and die after pulmonary edema.

How to identify chicken flu: diagnosis

Pathology is diagnosed after autopsy of the dead carcass. Before the birds die, infection can be determined by symptoms. In the laboratory, influenza is detected by isolating a strain from pathological material. Blood serum analysis is done at different stages of the disease. These signs indicate the presence of “chicken plague”.

Is treatment possible?

It is useless to treat chickens for a viral disease; scientists have not come up with optimal therapy. You can only take preventive measures on an ongoing basis. If bird flu has been detected in nearby regions, the bird should be completely isolated and kept in a closed place for 21 days in quarantine. If primary symptoms are detected, call the veterinary service.

How to deal with sick individuals

All birds affected by the influenza virus are killed to prevent further spread of pathogens. It is recommended to burn carcasses in designated areas. It is undesirable to eat the meat of sick individuals.

How can humans protect themselves from bird flu?

To prevent farmers from becoming infected with bird flu, the following rules should be followed:

• prevent children from interacting with wild waterfowl;
• if there are sick birds in the flock, when interacting with the entire group, wear a respirator, mask and gloves;
• use replaceable shoes when working in the chicken coop, and then thoroughly wash your hands and face with soap, spray your clothes with disinfectants to which viral agents are sensitive;
• Always store meat and eggs in separate containers in the refrigerator.

If a person exhibits the first symptoms of chicken flu, he should immediately consult a doctor.

Prognosis and prevention

According to experts, no amount of prevention can guarantee 100% protection of birds from bird flu. If you act comprehensively, you can create a reliable barrier that can overcome viral microorganisms. The main preventive measures are in the following aspects:

• keep chickens in a chicken coop so that they do not interact with wild birds;
• limit the access of domestic animals to water bodies, and in the event of focal outbreaks, from possible places of residence of wild birds;
• strictly control the food and water quality consumed by domestic birds;
• regularly disinfect feeders, drinkers and poultry houses;
• organize a balanced diet for chicks from their first days of life, introduce vitamins into the menu;
• if infection is suspected, spray Terramycin at a 20-centimeter distance from sick chickens;
• disinfect birds with Chlortetracycline, adding it to feed mash at the rate of 0.3 g per 1 kg of bird weight.

If preventive measures are taken, it will be possible to protect chickens from bird flu by 90%.