Etiological Analysis of Chicken Encephalopathy

Chicken encephalopathy refers to the disease caused by the invasion of chicken brain tissue. The main manifestations are a variety of neurological symptoms, such as head and neck tremor, movement disorder, wing and leg paralysis, crooked neck, rotation and so on. The causes of the disease are varied, including bacterial, viral, metabolic, toxic and so on.

Caused by E. coli invading brain tissue.

Autopsy showed large grayish-white necrosis and depression of beans in the posterior part of the cerebral hemisphere.

Clinical symptoms can be seen head and neck tremor, standing instability and so on.

At the time of diagnosis, the necrotic brain tissue was aseptically taken and cultured in McConkey medium to grow red medium-sized colonies. Gram staining was identified as g-bacilli, usually confirmed as Escherichia coli by microscopic examination.

In terms of treatment, drug sensitivity test was used to screen effective antimicrobials.

Also known as brain-type white dysentery, is caused by salmonella invading brain tissue.

The changes of autopsy and clinical symptoms were similar to those of Escherichia coli encephalitis. Gram-negative bacilli can be detected under microscope. Small white colonies were grown in S.S medium and identified by biochemical test as Salmonella pullorum.

The treatment is similar to Escherichia coli encephalitis.

Also known as epidemic tremor. A central nervous system damaging infectious disease caused by encephalomyelitis virus. It mainly damages the chicks under 1 month old.

Diseased chicks have typical symptoms such as head and neck tremor, with a mortality rate of 10% to 30%. Laying hens only show a temporary decline in egg production, and chicks hatched with poisoned eggs show typical symptoms.

The characteristic pathological changes can not be seen in the naked eye, and the histopathological changes are of diagnostic significance, mainly in the brainstem, especially in the medulla oblongata, with central chromatin dissolution, non-suppurative encephalitis and vascular sheath infiltrated by cells. glial cell proliferation. A preliminary diagnosis can be made by the age of onset, typical head and neck tremor and other neurological symptoms. Histopathological examination is helpful to the diagnosis, and it can be confirmed by isolating the virus if necessary.

Vaccination of breeder flocks is an effective way to prevent this disease.

Caused by Newcastle disease virus invading brain tissue.

The main symptoms are crooked neck, numb legs, reverse expansion of angle bow, turning in circles and so on.

Postmortem examination showed meningeal congestion and hemorrhage. Histopathological examination showed changes of non-suppurative encephalitis. In addition, as a characteristic of differential diagnosis, chickens with Newcastle disease often show tracheal annular bleeding, duodenal jujube-like bleeding, cecal tonsil and rectal bleeding.

Hi test can also be used to help diagnose.

3. Metabolic encephalopathy-encephalomalacia caused by se-ve deficiency

Se-ve deficiency encephalopathy mainly affected 2Mel 4-week-old chickens.

The main manifestations are ataxia, leg spasm, head backward or downward pausing or flapping wings while falling backward or forward, and finally died of spasm.

Autopsy showed cerebellum and cerebellum, medulla oblongata edema, hemorrhage, brain parenchyma swelling and softening, yellowish, severe green. In addition to brain changes, pancreatic necrosis, subcutaneous yellow jelly-like edema and white stripe necrosis of chest muscle were common.

Treatment can be mixed with se-ve powder or "vigorously replenish" drinking water, the symptoms will soon disappear.

Toxic encephalopathy is caused by the invasion of brain tissue by toxic substances. The substances that cause poisoning are moldy feed, chemical drugs and so on. Mildew feed poisoning is because the feed contains a large number of bacteria, mold and toxins. Generally speaking, the cause of chemical drug poisoning may be miscalculation or uneven mixing.

After poisoning, it is characterized by excitement, forward or backward, and turning in circles.

In addition to meningeal congestion and hemorrhage, the main autopsy changes were hemorrhagic inflammation of digestive tract, gallbladder filling, incomplete blood coagulation and major death in chickens.

If you stop feeding moldy feed and chemicals in time, and give large amounts of electrolytes and multivitamins, the condition will be alleviated quickly.

To sum up, in the diagnosis of such diseases, the epidemiology and feeding management of chicken flocks should be investigated in detail, especially the feed quality and nutritional composition, and the manifestations and characteristics of neurological symptoms should be observed. On the basis of clinical autopsy, histopathological examination and pathogen isolation were performed. When suspected of poisoning, it is necessary to find out the possible factors and conditions of poisoning.