Listeriosis: Circling disease

By Deb Haines

Listeriosis, or Circling disease, is a sporadic bacterial infection that affects a wide range of animals, including people and birds. It is seen worldwide, more frequently in temperate and colder climates. There is a high incidence of intestinal carriers. Encephalitis or meningoencephalitis in adult ruminants is the most frequently recognized form.

Sometimes called Silage sickeness, Listeriosis, is a central nervous system and digestive system infection caused by the bacterium Listeria monocytogenes. This bacterium is resistant to a wide range of temperatures. It can survive in temperatures ranging from 39 degrees Fahrenheit to 111 degrees Fahrenheit (4 C to 44 C).Listeria monocytogenes lives in the soil and in animal intestinal tracts. It may also live in spoiled silage where the pH is less acidic than in good quality silage.

In goats it’s transmitted via the oral fecal route usually when animals injest contaminated water or feed, or by fecal shedding of L moncytogenes. Infection can also occur by inhalation. infected animals can die if improperly treated. Listeriosis (circling disease) Listeria monocytogenes, the bacteria that causes listeriosis is widely distributed in nature and is found in soil, feed stuffs, and feces from healthy animals. It is most commonly associated with the feeding of moldy silage or spoiled hay, but because the organism lives naturally in the environment, listeriosis may occur sporadically

It can be presented in two forms: Encephalitic form charaterized by encephalitis or meningoencephalitis ( inflammation of the brain) This form contributes to the highest mortality rate. The bacterium enters the body through an opening in the mucosa of the oral cavity and migrates to the brain where it multiplies and causes inflammation. This form is where you see signs that include incoordination, circling in the same direction, seizures, hind limb paralysis, facial nerve disorders (facial paralysis, ear droop, excessive salivation, slack jaw, impaired swallowing), keratitis (cornea inflammation), and a very high mortality rate.

Septicemic Form (blood-borne): The bacteria enter through the intestines. The signs are diarrhea, abortion, and death.

Disease Transmission: Listeriosis can be contagious between animals through inhalation or ingestion (eating) of the bacteria. Ingestion could occur by eating pasture, hay, or silage that was contaminated with feces containing Listeria monocytogenes. Lesions or breaks in the membranes of the mouth can allow the organisms to enter the body.

This disease is zoonotic so take appropriate precautions. Human infection could result from consumption of unpasteurized milk and milk products and from handling the placenta, fetuses, or even newborn kids of infected animals. Precautions include using gloves when handling aborted material and only consuming milk products from pasteurized milk. All suspicious material should be handled with caution. This includes all dead animals and any aborted fetuses. Extra caution should be used when performing a necropsy on any animal suspected of having listeriosis. Infected female animals may harbor the bacteria in their milk. Listeriosis is a public health concern in these animals since the bacteria may survive certain forms of pasteurization.

Symptoms in goats and sheep

Some of the first signs observed in goats and sheep include depression, decreased appetite, disorientation, head tilt, and circling. As the disease progresses,facial paralysis may develop. The paralysis usually affects only one side of the face, causing the ear and eyelid to droop, the muzzle to be pulled to one side, and a lack of muscle tone in the lip of the effected side. Profuse salivation may also be observed. Sick animals may also be unable to stand or fall when standing. They may also exhibit involuntary running movements while lying down. fever for a day is often seen with listeria cases . many have a fever on the first day.

NOTE….Does that abort should be isolated and all aborted materials burned or buried. Kids should only be fed pasteurized colostrum or milk. Suspect recently introduced animals.

Successful treatment requires detection early in the course of the disease. Large doses of antibiotics such as penicillin are generally given(drug of choice) for treating listeriosis . Goats and sheep that have an acute form of listeriosis and death occurs in 4-48 hours. Recovery is rare

Treating Listeriosis

Recommended treatment.. Penicillin works well on gram positives (listeria is a gram positive)
Penicillin at 1cc per 15 lbs and given subq ( under the skin) every 6 hours like clockwork until see major improvement and can walk, then drop down to every 8 hours for a few days and make sure still OK, then down to every 12 hours and see if stays OK .. then once a day ,if ever the signs return, go back to the every 6 hours and start over to wean off
Polio is treated withvit B complex at 1cc per 20 lbs, also every 6 hours
treating for both at the same time is common

Fluids and electrolytes are necessary if the infected animal is having difficulty eating or drinking. Any feed (spoiled silage) suspected to be the cause should be removed. Isolate sick from healthy animals to prevent the spread of disease between animals.

Recovery Recovery depends primarily on early intervention with high doses of antibiotics. In cases of severe encephalitis, death may occur despite antibiotic treatment. Listeriosis can sometimes take up to two weeks or more for recovery. Each goat/sheep is different.

KEEP IN MIND

Does that abort should be isolated and all aborted materials burned or buried. Kids should only be fed pasteurized colostrum or milk. Suspect recently introduced animals.

Stop feeding poor quality silage and clean floors and pens. No vaccine is currently available.

Successful treatment is dependent upon prompt diagnosis.The survival of an animal depends on whether diagnosis is made at an early stage and correct treatment applied.

Discard spoiled feed and hay

Improve sanitation of pens water supply pasture,and housing.

Keep wild birds away from the herd as much as possible as these birds may serve as vectors for the disease.aborted animals,and newborns of infected does.

Always wear gloves when handling fetuses and specimens from aborted does.

If a doe has listeriosis,feed kids pasteurized or powdered colostrums,milk,or a milk substitute

If an outbreak of listeriosis occurs, ill animals should be isolated from healthy animals to prevent the spread of disease between animals.

To prevent listeriosis, care should be taken to avoid feeding livestock spoiled silage. Ensiling corn before it becomes too mature and feeding grass silage that contains additives may also help prevent listeriosis. Crops prepared under these conditions create silage with a more acidic pH which inhibits multiplication of

Listeria monocytogenes. Avoid pastures that are boggy and areas where the soil has a high pH. Rough, coarse feeds that have the tendency to injure the mouth should also be avoided. Additionally, if an outbreak of listeriosis occurs, ill animals should be isolated from healthy animals to prevent the spread of disease between animals.

If Death Occurs

A definitive diagnosis can only be made postmortem by histopathology of the pontomedullary region of the brainstem and by bacterial culture. Listeriosis may be diagnosed by analyzing cerebrospinal fluid (CSF) collected from the lumbosacral spinal region. The CSF will have an elevated protein concentration, and large mononuclear cells may also be present microscopically. The diagnosis can be confirmed by isolation and identification of the bacteria. This can be accomplished by submitting specific organs or specimens to a veterinary diagnostic laboratory. The brain should be submitted if there has been nervous system involvement. If abortion has occurred, the placenta and fetus should be submitted. Specimens that may help confirm the diagnosis include spinal fluid, nasal discharge, urine, feces, or milk. These specimens are often only helpful if the animal has septicemia (organisms in the blood).