Bovis ISSN 2398-2993

Actinomycosis

Synonym(s): Lumpy jaw

Contributor(s): Ash Phipps , Neil Paton

RVC logo

Introduction

  • Cause: Actinomyces bovis.
  • Signs: often presents as unilateral swelling of the mandible +/- maxilla. The affected animal may show other local and systemic clinical signs depending on the severity of the condition.
  • Diagnosis: definitive diagnosis is based in microscopic examination of the thick pus and yellow granules.
  • Treatment: iodides and/or sulphonamides parenterally or orally. Some cases may require surgical debridement.
  • Prognosis: early cases respond well to treatment. However, advanced cases the prognosis is poor.

Pathogenesis

Etiology

  • Actinomyces bovis which is gram positive club shaped filamentous anerobe bacterium.
  • This organism is an obligate inhabitant of the oral cavity of cattle.

Predisposing factors

General

  • Opportunistic infection.
  • Grazing abrasive feed.

Specific

Pathophysiology

  • The organism gains access to bony structures via lymphatic system from the oral cavity through wounds of the buccal mucosae, ulcerative lesion of the buccal mucosae, tooth root abscess or tooth eruption.
  • It is common to have a concurrent infection with Staphylococcus aureus Staphylococcus spp and Arcanobacterium pyogenes.
  • Pyogranulomatous inflammation results in suppurative tracts that permeate the medullary spaces leading to osteomyelitis and multiple foci of bone reabsorption and proliferation.
  • Exostosis occurs resulting in gross deformities of the affected bone.
    • The exostosis can result in the mal-alignment of the molars and premolars and impair feeding and rumination.
  • Discharging sinuses may form, most commonly on the underside of the affected jaw.
  • The thick pus (resembles honeycomb) discharging from the sinus contains numerous yellow granules, approximately 1-2mm in diameter (‘sulphur granules’).

Timecourse

  • Enlargement and progression the lesion may occur rapidly (over several weeks) or slowly (over several months).

Epidemiology

  • Sporadic condition.
  • Usually occurs in an individual animal.

Diagnosis

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Treatment

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Prevention

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Outcomes

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Further Reading

Publications

Refereed Papers

  • Recent references from PubMed and VetMedResource.
  • Pine L & Overman J R (1963) Determination of the structure and composition of the ‘sulphur granules’ of Actinomyces bovis. Microbiology 32 (2), 209-223 PubMed.
  • Morris E O (1951) The life cycle of Actinomyces bovis. Epidemiology & Infection 49 (1), 46-51 PubMed.
  • Plummer P J G (1946) Actinomycosis: Histological Differentiation of Actinomycosis and Actinobacilliosis. Canadian journal of comparative medicine and veterinary science 10 (12), 331 PubMed.

Other sources of information

  • Parkinson T J, Vermunt JJ & Malmo J (2010) Diseases of cattle in Australasia: a comprehensive textbook. New Zealand Veterinary Association Foundation for Continuing Education. pp 611-612.
  • Otto M et al (2006) Veterinary Medicine: A textbook of the diseases of cattle, horses, sheep, pigs and goats. Elsevier Health Science. pp 1045-1047.


ADDED