Introduction

Classification

Taxonomy

• Kingdom: bacteria.
• Phylum: Firmicutes.
• Class: Clostridia.
• Order: Clostridiales.
• Family: Clostridiaceae.
• Genus: Clostridioides.

Etymology

• Gk: Clostridium: klōstēr - a spindle, in reference to their rod shape.

Active Forms

Clinical Effects

Epidemiology

Habitat

• Worldwide distribution.
• Normal intestinal flora of cattle.
• Ubiquitous in soil.
• Very stable in the environment.
• Dormant spores have been found in the muscle (eg C. novyi type B/C. chauvoei), spleen (eg C. chauvoei) and liver (eg C. hemogloinuria) of cattle.
• Fewer than 20 of 100 spp. are pathogenic.

Lifecycle

• Clostridial organisms occur as normal flora of cattle but can become problematic when risk events happen (eg dietary stress, injury, changes in management, parasitism) that allow favorable growth environments.
• Clostridial organisms can be found as living cells (vegetative) or as dormant spores.

Transmission

Pathological effects

• Often the first clinical signs is death.
• Other clinical signs include:
  • Depression, fever, abdominal pain, dyspnea, dysentery, and hemoglobinuria (eg C. hemolyticum).
  • Emphysematous swelling (C. chauvoei).
  • Anorexia, intoxication, and high fever, as well as local lesions (C. septicum).
  • Motor paralysis (C. botulinum types A-G).
• Immunity usually depends on the production of antitoxins.
• Infection may be endogenous from the host's gut, or exogenous from the environment.
• Pathogenic species can be divided into 4 groups:
  • Neurotropic - produce potent neurotoxins, eg C. botulinum Clostridium botulinum.
  • Histotoxic - produce less potent exotoxins and are invasive, eg C. perfringens type A.
  • Enterotoxic - toxins are absorbed from the gut, eg C. perfringens types A-E Clostridium perfringens type C.
  • Produce enteric disease. In some host species this is a consequence of antibiotic use, eg C. difficile.

Other Host Effects

• Many clostridial species are commensals, especially in the gastrointestinal tract.

Control

Control via animal

• Control methods, depend on whether disease is due to an invasive, eg C. perfringens Clostridium perfringens or non-invasive, eg C. tetani Clostridium tetani species.
• Prevent cattle from grazing areas adjacent to recent excavations or which have recently been flooded (C. chauvoei).
• Prevent dietary deficiencies (C. botulinum Clostridium botulinum).

Control via chemotherapies

• Early treatment with penicillin Penicillin G or tetracyclines Chlortetracycline Oxytetracycline at high doses.

Control via environment

• Avoid feeding contaminated feed (eg silage cut from fields where dead animals have been - C. botulinum Clostridium botulinum).

Vaccination

• Wide variety of vaccines are available - singly, or in combination formats:
  • Commonly a 4-way vaccine (killed cultures of C. chauvoei, C. septicum, C. novyi, and C. sordellii) is used to protect against blackleg and malignant edema.
  • Vaccines which protect against C. perfringens types C and D are also available and used to protect cattle against enterotoxemias, whilst vaccines against C. hemolyticum can be used to protect against infectious necrotic hepatitis. These vaccines can cause localized tissue reactions should therefore be administered SC to cattle in the neck.
  • Vaccines exist against types C and D toxoid.

Diagnosis

Further Reading

Publications

Refereed Papers

• Recent references from PubMed and VetMedResource.
• Abdel-Moein K A & Hamza D A (2016) Occurrence of human pathogenic Clostridium botulinum among healthy dairy animals: an emerging public health hazard. Pathog glob health 110 (1), 25-9 PubMed.
• Fohler S, Klein G, Hoedemaker M, Scheu T, Seyboldt C, Campe A, Jensen K C &
  Abdulmawjood A (2016) Diversity of Clostridium perfringens toxin-genotypes from dairy farms. BMC Microbiol 16 (1), 199 PubMed.
• Lindström M, Myllykoski J, Sivelä S & Korkeala H (2010) Clostridium botulinum in cattle and dairy products. Crit rev food sci nutr 50 (4), 281-304 PubMed.
• Princewill T J, Agba M I & Jemitola S O (1985) Animal feeds as likely vehicles of clostridial infections in livestock. Microbios 42 (169-170), 155-62 PubMed.
• Princewell T J T & Agba M I (1982) Examination of bovine faeces for the isolation and identification of Clostridium species. Journal of applied bacteriology 52, 97–102 PubMed.