• 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
    • Keeping Texas Prepared – TVMDL’s Impact on Texas
    • 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

Blackleg (Clostridial myositis) in cattle

February 15, 2018 by Mallory Pfeifer

Blackleg (Clostridial myositis) in cattle
By Jay Hoffman, DVM, PhD

With over 800,000 tests run annually, TVMDL encounters many challenging cases. Our case study series will highlight these interesting cases to increase awareness among veterinary and diagnostic communities.

Blackleg is an infectious, non-contagious disease caused by Clostridium chauvoei.  Infection occurs when animals ingest bacterial spores while grazing. The bacterial spores penetrate the intestine and are disseminated via the bloodstream to the skeletal muscle, where the spores remain dormant. Following an event that causes low oxygen conditions (i.e. bruising or damage to the muscle) in infected tissue, the spores germinate, multiply and produce toxin that results in muscle necrosis and hemorrhage. The animals affected by blackleg are usually well fed animals between 6 months and 2 years of age.  The cause of death in affected cattle is usually acute toxemia. The course of the disease is often between 12-48 hours and clinical signs are often absent; however, animals may exhibit signs of lameness, tachycardia, fever, anorexia, rumen stasis and lethargy.  Blackleg is primarily a disease of pastured cattle with the majority of the cases occurring during the summer months.

Throughout 2017, the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) diagnosed a significantly increased number of blackleg cases.  Although a cause for the increased incidence of cases has not been conclusively determined, a possible explanation are the environmental changes that resulted from the unusual weather conditions experienced during 2017.  Specifically, it is speculated that the extreme amounts of rain and flooding associated with Hurricane Harvey and the subsequent dry conditions worked to stir up the soil leading to exposure of deeply hidden bacterial spores.

The affected animals presented to TVMDL for necropsy ranged in age from 4 months to up to 1 year of age.  The gross lesions included variably sized areas of skeletal muscle that was dark red and contained gas bubbles (necrotizing myositis). Due to the intramuscular gas bubbles, affected sections of skeletal muscle would often float in formalin.  Most of the affected animals had a concurrent fibrinous pericarditis and necrotizing myocarditis.  The skeletal muscle and myocardial lesions typically had the faint to pervasive odor of rancid butter.  The diagnosis of blackleg was based on the characteristic gross lesions and a positive fluorescent antibody test results on affected tissues.  The cases of blackleg at TVMDL appeared to peak after Hurricane Harvey and continued through December 2017.

To learn more about the these cases, contact Dr. Jay Hoffman, Pathology Branch Chief at the College Station laboratory. Visit tvmdl.tamu.edu  or call 1.888.646.5623 to learn more about our test catalog.

Skeletal muscle from calf depicting black muscle tissue that is confident with Blackleg.

Skeletal muscle from calf. Characteristic necrotizing myositis and gas bubble formation associated with blackleg.

Filed Under: Case Study Tagged With: blackleg, bovine, case study, cattle, colle, college station, pathology, TVMDL

Primary Sidebar

Latest Case Studies

  • Cytauxzoon felis infection in two cats

    October 10, 2023

  • Historical overview of anthrax in Texas’ livestock population (1974-2022)

    August 11, 2023

  • Juvenile lymphoma in an Angus calf

    July 11, 2023

  • 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

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
Copyright Texas A&M Veterinary Medical Diagnostic Laboratory© 2023

State of Texas

  • Texas.gov Portal
  • Texas Veterans Portal
  • Statewide Search
  • Texas Homeland Security
  • Risk, Fraud, & Misconduct Hotline
  • Compact with Texans
  • State Link Policy

Policies

  • Clients Rights and Responsibilities
  • Privacy and Security Policy
  • Accessibility Policy
  • Open Records/Public Information
  • Veterans Benefits
  • Military Families
  • Equal Opportunity
  • 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