• Skip to primary navigation
  • Skip to main content
  • Skip to primary sidebar
  • Skip to footer
  • Locations:
  • Canyon
  • Center
  • College Station
  • Gonzales
  • TVMDL Career Center
  • Contact Us

Texas A&M Veterinary Medical Diagnostic Laboratory

Apple App

download on the Apple App Store
download the app on Google Play

Search

Translate:

  • Find a Form
  • Deliver a Sample
    • Specimen Collection Information
    • Packaging Samples for Shipment
    • Drop Off a Sample
    • Cremation
    • Order Supplies
  • Client Portal
    • Get Test Results
    • SVA Portal
    • Pay a Bill
  • Become a Client
  • Resources
    • TVMDL Bovine Testing Guidance and Reference Material
    • Diagnostic Plans
      • Bovine Syndromic Diagnostic Plans
      • Equine Syndromic Diagnostic Plans
      • Small Ruminant Syndromic Diagnostic Plans
      • Small Animal Syndromic Diagnostic Plans
    • Education Library
    • Case Study Library
    • Electronic Reporting: QR Coding Process
    • CoreOne Resources
  • About Us
    • Locations and Hours
    • Agency Leadership
    • Speaker’s Bureau
    • Texas Pullorum-Typhoid Program
    • TVMDL Mobile app
    • Contact Us
  • Locations
    • College Station Laboratory
    • Canyon Laboratory
    • Center Laboratory
    • Gonzales Laboratory
  • Contact Us

Listeriosis in a goat doe

January 3, 2022 by Mallory Pfeifer

Listeriosis in a goat doe
Guy Sheppard DVM, Jessie Monday DVM, MS, Laura Rice DVM, MS, DACVP

Samples from a one-year-old Boer goat doe were received at the TVMDL for testing.  The doe had displayed neurological signs including unilateral paresis, droopy lip and hypersalivation, torticollis upon stimulation, obtundation, and lateral recumbency.  The goat was also febrile. Clinical differentials included listeriosis, polioencephalomalacia, bacterial meningitis, and rabies virus. Treatment consisted of antibiotics, anti-inflammatory drugs, and vitamins B1 and B12. The patient responded to initial treatment and supportive care.

The goat died the following day, and tissues were submitted to TVMDL for diagnostic investigation. Due to the fact that several people were exposed to saliva from this goat, sections of the brain were submitted to the Texas Department of State Health Services for rabies testing.

After a negative rabies test result was received, histopathology exam of the brain tissue was conducted along with a culture of the brain tissue.  The most significant finding on histopath was necrosuppurative meningoencephalitis (Figure 1), and Listeria spp. was isolated and identified from the culture.

Listeria monocytogenes, the cause of encephalitic listeriosis, can also cause abortions, neonatal septicemia, ophthalmitis, and mastitis in small ruminants. L. monocytogenes are gram-positive, non-acid-fast facultative microaerophilic bacteria ubiquitous in outdoor environments of temperate climates. The bacteria can be shed in feces, tears, nasal secretions, uterine fluid, and milk. Bacteria can remain viable in soil, feces, and contaminated feed for months to years.

Neurologic listeriosis in ruminants can manifest as focal, multifocal, or diffuse encephalitis, meningoencephalitis, or myelitis. Encephalitis localized to the brain stem is the most frequently recognized syndrome in small ruminants. Sheep and goats often present acutely with asymmetric central nervous system signs including ataxia, circling, head pressing, depression, and other neurologic examination abnormalities consistent with meningitis and focal brainstem lesions (microabscesses). Cranial nerve abnormalities, including unilateral nasal deviation, lip droop, dropped jaw, ear droop, head tilt, dysphagia, unilateral tongue paresis, and eyelid droop are common. Exposure keratitis can occur secondarily to the cranial nerve abnormalities. Metabolic abnormalities, dehydration, decreased rumen motility, and metabolic acidosis secondary to decreased salivary bicarbonate are potential clinical sequela to manage.

Clinical signs can vary depending on the location of lesions and the duration of infection. Clinical disease progression is rapid and severe, with a high fatality rate. The disease in small ruminants tends to be more acute and more often fatal when compared to neurologic listeriosis in cattle. The disease usually affects only one or two animals in a population but outbreaks with multiple fatalities in a herd have been reported.

Antemortem testing options include cerebral spinal fluid (CSF) cytology, CSF culture or L. monocytogenes rtPCR, CBC, and chemistry profile.

Listeriosis is a common diagnostic laboratory diagnosis in postmortem caprine cases submitted for work up of neurologic disease in the United States. Bacterial culture for Listeria spp. from appropriate fresh tissue samples is more successful in small ruminants than cattle. In cases where Listeriosis is the primary differential but culture fails to recover Listeria spp., IHC for listerial antigens can prove useful, even in cases lacking significant or pathognomonic histopathology lesions. Molecular testing (rtPCR) is also a sensitive methodology that can be applied to diagnostic investigations before, concurrent with, or after histopathology and culture. Postmortem CSF fluid can also be diagnostically rewarding when submitted for cytology or pathogen detection via rtPCR if brain tissue is not available. Culture and rtPCR of CSF is less often rewarding compared to appropriate sections of affected fresh brain tissue.

Figure 1: Photomicrograph depicting necrosuppurative encephalitis with microabscessation in the brainstem of the goat.

Resources:
Allen, Andrew L., Brad A. Goupil, and Beth A. Valentine. “A Retrospective Study of Brain Lesions in Goats Submitted to Three Veterinary Diagnostic Laboratories.” Journal of Veterinary Diagnostic Investigation 25, no. 4 (July 2013): 482–89. https://doi.org/10.1177/1040638713493627.

Baird, A. N., and D. G. Pugh. Sheep and Goat Medicine. WB Saunders Company, 2012. pgs 390-391.

Johnson, Gayle C., William H. Fales, Carol W. Maddox, and Jose Antonio Ramos-Vara. “Evaluation of Laboratory Tests for Confirming the Diagnosis of Encephalitic Listeriosis in Ruminants.” Journal of Veterinary Diagnostic Investigation 7, no. 2 (April 1995): 223–28. https://doi.org/10.1177/104063879500700210.

Smith B.P. Large Animal Internal Medicine. Mosby, 2015. pgs 969-97.1

Filed Under: Case Study Tagged With: anatomic pathology, caprine, college station, goat, histopathology, pathology, TVMDL

Primary Sidebar

Latest Case Studies

  • Neurologic Disease due to Bovine Herpesvirus-5 (BHV-5) Infection in a 3-week-old Charolais mix calf

    February 27, 2023

  • Rare case of ocular onchocerciasis in a dog from south Texas

    January 25, 2023

  • Cerebrospinal Nematodiasis (Visceral Larval Migrans) in Birds

    September 13, 2022

  • Spironucleosis (Hexamitiasis) in Quail

    August 9, 2022

  • Endocarditis in a White-Tailed Deer Caused by Trueperella pyogenes

    August 9, 2022

Footer

For Employees

  • Employee Email
  • TVMDL Rules & Procedures
  • TVMDL Career Center
  • Emergency Alert Systems
  • AgriLife People Directory
  • AgriLife Administrative Services
  • TAMUS Single Sign On
  • Facebook

State of Texas

  • Texas.gov Portal
  • Texas Veterans Portal
  • Statewide Search
  • Texas Homeland Security
  • Risk, Fraud, & Misconduct Hotline

Policies

  • Privacy and Security Policy
  • Accessibility Policy
  • Texas A&M AgriLife
  • Texas A&M Veterinary Medical Diagnostics Laboratory
  • Texas A&M Forest Service
  • Texas A&M AgriLife Extension Service
  • Texas A&M AgriLife Research

483 Agronomy Rd
College Station, TX 77843