Nervous System Diseases Affecting Chickens

Chicken that died from Disease

There are Many Diseases That Can Affect the Nervous System of Your Flock.


As an owner of a small flock of chickens, one of your primary concerns will be keeping your birds healthy.

By understanding the various health risks that chickens face, you’ll be better able to recognize symptoms when they crop up and treat outbreaks quickly.

On this page, we’ll address a few common chicken diseases that attack the nervous system. If you start to notice symptoms of any of these diseases, it’s important to treat your chickens quickly. The sooner you recognize the signs, the better your chances are of preventing further contagion.


Avian Encephalomyelitis Virus

Avian encephalomyelitis virus (or AEV) is a virus that attacks the central nervous system and is particularly prevalent in young poultry. Chickens, turkey and pheasants are especially prone to this disease.

Spreading the Disease

The disease can be spread vertically from the mother hen to the chicks as well as horizontally through contact with other infected members of the flock as well as oral ingestation of the virus through food or water contaminated by the virus through fecal droppings.

Signs & Symptoms

Symptoms will come on rapidly in young chicks. You may first notice a pronounced dullness in the eyes, followed by tremors and a marked loss of muscle control (especially in the head and neck). Tremors are the characterizing symptoms of the disease.

Treatment

Unfortunately, there currently is no treatment for AEV. If your flock is affected by AEV, you may need to immediately cull and incinerate severely infected birds. Birds that survive AEV develop immunity and cannot get reinfected.

Prevention

Because AEV is a virus, vaccinations are available. You’ll want to check with your local avian vet for availability and pricing. Sourcing your hatching eggs from immunized breeders is also a good step. Because the disease is spread through fecal contamination, always provide your flock with plenty of fresh water and food.

 

Botulism

Avian botulism causes paralysis of the muscular and nervous systems. The disease is caused when a bacterial toxin produced by Clostridium botulinum is consumed by the birds. 

Spreading the Disease

This toxin is found in decaying plant or animal matter. If a toxin-containing material (like pond mud or maggots) is eaten by your chickens, you may be facing an outbreak of botulism.

Signs & Symptoms

Symptoms of botulism include a gradual weakness and paralysis of the legs, wings and neck, followed by sudden death. You may find that the feathers of an affected bird are easily pulled, and you may discover maggots in the dead bird’s crop.

Treatment

Afflicted birds can be treated with a course of antibiotics as well as supplemental vitamins. Birds that survive the first 48 hours have a strong chance of full recovery. If the infection is mild, the birds may recover on their own. Always provide plenty of fresh, clean food and water.

Prevention

Because chickens are omnivores and will eat pretty much anything, it is especially important to keep them away from rotting flesh like dead rats and nice as well as other sources of contamination. Botulism can be largely prevented by preventing access to suspect food and water sources. Always provide plenty of fresh, clean food and water.

 


Marek’s Disease

Marek’s is an unfortunately prevalent, contagious disease among chickens. It’s so common that nearly all birds have been exposed at some point. There are four strains of this viral disease:

  • Neural
  • Ocular
  • Cutaneous
  • Visceral

Marek’s is the result of six herpes strains, and it typically affects young chicks. Newborn chicks are usually protected for the first few weeks of life due to antibodies from their mother, but become susceptible at around 3-4 weeks of age.

Spreading the Disease

It is spread through direct contact – either bird-to-bird, through inhalation (infected dander or feathers), or through bugs that live in the coop.

Signs & Symptoms

The neural form causes a progressive paralysis in the legs and wings, often accompanied by diarrhea. Death quickly follows as immobile birds cannot reach food and water.

Treatment

There is currently no treatment for Marek’s and the expected mortality rate for infected birds is extremely high.

Prevention

Marek’s can be largely prevented through good sanitation and ventilation, along with vaccination. Many hatcheries will vaccinate the newborn chicks for a nominal fee.  Infected birds should be culled immediately.


Newcastle Disease

This is one of the more serious nervous system diseases affecting poultry in the world. In some countries it is endemic. It’s a highly contagious viral disease that can be transmitted to humans through contact with an infected bird. Newcastle can cause flu like symptoms in humans, otherwise it generally it poses no serious health risks to humans. 

Spreading the Disease

Newcastle Disease is most commonly spread through the infected chickens' droppings (manure) and respiratory secretions from the nose and mouth as well as ocular (eyes) secretions.

Signs & Symptoms

Symptoms can range from fairly mild to such severity that infected birds may die without a single warning sign.

Severe illness will result in obvious nervous problems, including muscle tremors, a twisted head, drooping wings, and paralysis. Other symptoms may include coughing, sneezing, depression, and diarrhea.

Treatment

There is currently no treatment for Newcastle Disease. Anti-biotics may be given to control secondary infection symptoms.

Prevention

Vaccination can prevent outbreaks among your flock. The disease can be largely controlled through good flock hygiene and maintenance. Cleaning, pest control and proper carcass disposal are all important measures in the prevention of Newcastle Disease.

Encephalomalacia

Encephalomalacia is a disease that is thought to be triggered by lack of Vitamin E in the chicks' diet. It is sometimes referred to nutritional Encephalomalacia

Spreading the Disease

Encephalomalacia generally crops up in young birds within their first five weeks. This problem is typically brought about due to rancid feed – most often in high-fat diets.

Signs & Symptoms

This can result in a number of neural problems, including staggering, imbalance, uncontrolled movements and even paralysis.

Treatment

Fortunately, the condition is quite treatable with vitamin E and/or selenium supplements to the diet. In some cases, broad-spectrum antibiotics are also helpful.

Prevention

In most cases, the disease can be prevented by maintaining a good quality diet with proper levels of vitamin E, antioxidants and selenium.


Unfortunately many Nervous System Diseases of Chickens have no treatment, but with proper preventative measures, many of them can be avoided.

Return from Nervous System Diseases to Common Chicken Diseases

Protected by Copyscape Online Plagiarism Scanner