Peripheral neuropathy is a condition which develops as a result of damage to the chicken's peripheral nervous system---which interferes with proper functioning of the nerve impulses between the brain and spinal cord to other parts of the body, including muscle movement. Symptoms vary depending on whether motor, sensory, or autonomic nerves are damaged. They may also differ depending on whether it is an acute or chronic form.
Motor nerve damage
: Damage to the motor nerves is most frequently associated with muscle weakness. Other symptoms may include difficulty or inability to perch on the roosting bar at night, fasciculations (uncontrolled muscle twitching visible under the skin), muscle atrophy (severe shrinkage of muscle size), and change in voice or crow sound (for roosters).
Sensory nerve damage
: Damage to the sensory nerves causes a variety of symptoms because sensory nerves have a broad range of functions. This may result in decreased reaction to touch, pain, or change in temperature. There may also be a loss of reflexes and position sense--which may present as uncoordinated movements.
Autonomic nerve damage
: Damage to the autonomic nerves may cause a wide range of symptoms since the parasympathetic and sympathetic nerves of the peripheral nervous system control nearly every organ in the body.
Peripheral Neuropathy Causes
Peripheral neuropathy may be either inherited or acquired through disease processes or trauma. In many cases, however, a specific cause cannot be identified. Causes of peripheral neuropathy include:
- Physical injury (trauma) is the most common cause of acquired nerve injury.
- Diseases or disorders and their related processes (such as inflammation) can be associated with peripheral neuropathy.
- Kidney diseases: Kidney dysfunction can lead to abnormally high amounts of toxic substances in the blood that can damage nerve tissue.
- Infections: Viruses and bacteria that can attack nerve tissues include Marek's disease virus, retroviruses (reticuloendotheliosis virus), West Nile virus, and Toxoplasma gondii.
- Cancers: Can infiltrate nerve fibers or exert damaging compression forces on nerve fibers. Tumors also can arise directly from nerve tissue cells.
- Degenerative process: The Rhode Island Red chicken breed is genetically predisposed to developing idiopathic polyneuritis.
- Exposure to toxins: Such as lead, mercury, and arsenic can cause peripheral neuropathy. In addition, certain insecticides and solvents have also been known to cause neuropathies.