Diseases Of Chickens. Infectious. Part 1

2024 Author: Gavin MacAdam | [email protected]. Last modified: 2023-12-16 13:38

In previous articles on diseases of chickens, diseases of a non-infectious nature were described. This article on diseases of an infectious nature is purely advisory in nature and in the event of symptoms, a veterinarian's consultation is mandatory. Some viral diseases are capable of destroying 100% of the poultry population not only of one farm, but of a settlement as a whole. Cities and villages are being quarantined and the export of live and slaughtered poultry is prohibited. Such measures have been used all over the world for many decades. By strict measures, for example, in Germany, the bird plague virus was defeated and for more than 30 years it has not been remembered

Infectious diseases include viral, bacterial and parasitic diseases. Regardless of the nature of the disease, there is a list of the most common symptoms, such as: a rise in temperature up to 44 ° C, drowsiness, loss of strength, inflammation of the mucous membranes, the nasal passages and the oral cavity are covered with mucus, difficulty breathing. Wheezing is heard, the bird breathes with its open beak. Diarrhea is also a common symptom, the plumage near the cloaca becomes contaminated with feces, sticks together until a plug is formed. In general, plumage is a very clear indicator of the health and proper development of a bird. Normally, the plumage is clean with shine, bright according to the color.

Viral diseases

Newcastle disease (Pseudo-plague)

Viral disease with an incubation period of 3-7 days. A very unpredictable disease, since it can develop into an acute form in 1-3 days, leading to death, or it can turn into a chronic one and last 2-3 weeks. The bird has a chance to recover and gain natural immunity, but it is very small and incomparable with the danger of a pseudo-plague epidemic. When an autopsy of the first diseased bird confirms this diagnosis, the rest of the diseased bird is destroyed bloodlessly to prevent the spread of infection.

The main symptoms of the disease are pronounced swelling of the respiratory tract and, as a result, the bird walks with an open beak, making croaking sounds. Thick mucus completely covers the beak and nostrils, the bird sneezes and coughs. The cornea of the eye often becomes cloudy, general weakness, fever, which later turns into neurological symptoms: circular head movements, paralysis of the limbs and neck. Diarrhea with blood is also found (as the autopsy shows, the reason for this is numerous bleeding ulcers on the internal organs)

There is no drug treatment. As a prophylaxis, specific vaccines called "La Sota", "Bor-74" are used, which are injected into the nose or by drinking. They are recommended for poultry farms with more than 200 heads. If the diagnosis is confirmed, the sick bird is selected and sent to slaughter. Healthy individuals are constantly monitored for the smallest symptoms. All inventory (drinkers, feeders, flooring, perches) is changed and the room is sanitized with bleach or formalin solution. Birds are not allowed to walk in the open air, especially near other farms. It is forbidden to buy new birds until 30 days have passed since the last case of the disease. It is worth noting that this disease remains viable for a very long time in the external environment (in cool weather up to six months, but does not persist well in dry hot weather). It is also worth noting that this disease is transmitted to humans! In humans, it occurs in the form of ARVI, complicated by conjunctivitis.

Laryngotracheitis

Laryngotracheitis is a viral disease that mainly affects grown-up birds from 5 months to a year, less often chicks are susceptible to infection for 20-35 days. The disease begins mainly in the trachea region. At first, these are painful sensations in the trachea. The bird unnaturally stretches its neck, shakes its head. Later, breathing becomes difficult, wheezing appears. The mucous membrane is covered with curdled deposits. In severe form, when the head is shaken, these deposits are separated and come out interspersed with blood. As a consequence of inflammation of the conjunctiva, there is a noticeable photophobia. The reason for the death of the bird is suffocation.

Infection of a bird occurs through contact with secretions from the respiratory tract, even with a microscopic amount. The incubation period of the disease is from 2 to 30 days. The surviving bird carries the disease for another two years. Poultry vaccinated with a live vaccine is contagious for 90 days. Thus, once having entered the farm, this disease becomes stationary and returns again and again. The disease is activated in cool weather, when the young are transferred to a new room. Deteriorating conditions of detention, poor feeding, high humidity, poor ventilation can all give rise to a new outbreak of the disease.

There is no specific treatment, symptomatic drug treatment is used. The poultry is given antibiotics in combination with antimicrobial agents such as Furozolidone and vitamins such as Trivitamin, Dioxidin for external treatment of poultry, premises and equipment.

Bird flu

A sensational disease called a virus

H5N1 is a type of bird flu. Poultry is most susceptible to disease with subtypes H5 and H7. It has many developmental options, affecting both the respiratory and circulatory systems. The main symptoms are profuse mucus enveloping the respiratory tract, swelling and sticking of the eyelids. The respiratory system also clogs up as the mucus dries out, and the bird dies from suffocation. Another way of development of the disease is massive internal hemorrhages, edema of internal organs, hemorrhagic meningitis. Neurological symptoms such as cramps of the wings, neck also join; diarrhea (brownish-green discharge).

As in the case of other viral diseases, infection occurs through airborne droplets. This disease also lives for a long time in the external environment, remaining viable for up to six months in favorable conditions. There is no cure. Tough quarantine measures are being taken. A sick bird is separated and disposed of by a bloodless method (burned). A bird without symptoms is considered

CONDITIONALLY healthy and also subject to slaughter, but it is fit for consumption and processing. Since the disease is contagious to humans, the attendants are assigned to a specific chicken coop and are not allowed to visit other birds. The person must wear disposable clothing and undergo a daily medical check-up.

Quarantine measures are lifted after the following conditions are fully met:

• 21 days after disposal of the last diseased bird

• 21 days after the processing and sale of the last conditionally healthy bird

• complete sanitization of premises and equipment

• 21 days after the last personnel case.

It should be remembered that only specialists in the laboratory can make these diagnoses. These are all serious diseases that cause enormous economic damage, sometimes even on a national scale. Be vigilant and comply with all sanitary standards in your farms.