A muscle that is no longer subject to a voluntary control is said to be paralyzed. There are two different types of paralysis: flaccid paralysis caused by disease of the lower motor neurons or their fibers; and spastic paralysis which results from disease affecting cortical motor neurons or their fibers.
If the lower motor neuron in the spinal cord is destroyed by a disease such as polyomyelitis or if the peripheral nerve supplying the muscle (which contains the nerve fibers of the spinal neuron) is interrupted, the reflex arc responsible for muscle tone is interrupted. Muscle tone is abolished because the muscle is deprived of its innervation. The muscle becomes limp and undergoes severe atrophy.1
Tick Paralysis, an ascending paralysis of dogs and children, is caused by a protein toxin released by female ticks after a few days of feeding. The common ticks that bite dogs and cats are Ixodes scapularis and Ixodes pasificus. The other ticks only appear on dogs in shelters that have been wandering in tick-infested environments. They are found most commonly in and around the ears and armpits.
Ixodes holocyclus, also known as dog tick, scrub tick, or shellback tick, is dangerous to humans, livestock , and pets. Many fatalities have occurred as all that is needed to cause death, in a small animal, is one engorged female tick. Paralysis ticks are most active from August to December. An affected animal will need treatment.
Treatment of Tick Paralysis in Cats
There are three stages for tick paralysis caused by Ixodes holocyclus: removal of offending ticks; counteraction of circulating toxin, and supportive therapy. Ticks are best removed by sliding the blades of a partially opened pair of scissors between the tick and the animal's skin. Using the levering action, the tick can be maneuvered from the attachment site with its mouthparts intact. This strategy prevents additional release of toxin into the animal. Next, hyperimmune serum (a preparation with a high concentration of antibodies) may be administered intravenously to neutralize the effects of the circulating toxin.3
- An introduction to human disease: pathology and pathophysiology correlations. Leonard V. Crowley
- Shelter medicine for veterinarians and staff. Lila Miller, Stephen Zawistowski
- Feline Clinical Parasitology. Dwight D. Bowman, Charles M. Hendrix