COOPERATIVE KENTUCKY STATE UNIVERSITY FACT SHEET

Information about the Kentucky State University Cooperative Extension Program 2020

Neurologic Listeriosis in Sheep and Goats

Dr. Jerusha (Jessie) Lay, Assistant Professor of Animal Health

What Causes It?

Listeriosis is a common neurological disease in goats caused by the bacteria Listeria monocytogenes. Although can it be seen throughout the year, it is more commonly seen in the winter and spring months. The bacteria is extremely resistant and may grow in a wide range of temperatures. This is important to remember as freezing temps may not kill or prevent growth as it does in other bacteria. In a lab setting ‘cold enrichment’ actually promotes the growth of this organism. That’s why it’s not surprising that we see it in our colder weather months.

While listeria may also cause abortions or septic infections, in this article we will focus on the neurologic form.

Where Does It Come From?

Two common routes of transmission:

1. The most notable source, especially in cattle is from decaying vegetation. This may be in the form of round bales of hay that have begun to rot, silage not properly fermented, and feed bunks that are not cleaned regularly.
2. Healthy animals may have listeria in their GI tract. As it is shed through the feces and ingested by another animal, this may also be the cause for disease. This is considered fecal oral and may present if feed bunks or water troughs contain feces. If the animal is stressed or malnourished, it may increase incidence.

What are The Symptoms of Neurologic Lysteria?

Listeriosis has a much faster progression in small ruminants than it does in cattle. In severe cases death may occur 24-48 hours after the initial symptoms. At first animals are depressed and possibly off balance walking. Next is generally a unilateral facial paralysis (drooping of one side of the face). This continues to progress, animals often lose ability to swallow, and begin walking/falling in circles. The animals soon thereafter become unable to stand and if treatment is not successful die.