Diagnosing enterotoxemia in ruminants remains one of the most complex challenges in veterinary practice. The disease is mainly associated with Clostridium perfringens type A — an anaerobic bacterium naturally present in the gut, capable of multiplying extremely rapidly and producing a highly labile α-toxin, which is directly involved in the disease process.
Because of these biological characteristics, sampling, transport, and laboratory analysis must follow strict protocols to ensure reliable results. Even small deviations – such as delays after death or exposure to oxygen – can compromise diagnosis.
This practical guide, written by experts Luca Bano (Head of Microbiology & Diagnostic Laboratories at IZSVe) and Philippe Gisbert (Global Technical Manager at Ceva Santé Animale), provides step by step approach to the laboratory diagnosis of enterotoxemia, from field sampling collection to interpretation of results, helping veterinarians improve diagnosis accuracy and decision making.
In this booklet you will find…
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Why enterotoxemia diagnosis is so complex: understand the key biological
characteristics of Clostridium perfringens that impact every diagnostic step -
How to collect reliable samples in the field: a practical step-by-step procedure on the dead animal, from localization of the affected intestinal segment to intestinal loop ligation and biological sample handling procedures
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The 15-hour post-mortem rule: why timing is critical to avoid misleading laboratory results
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Anaerobic transport conditions: best practices for maintaining sample integrity (anaerobic conditions, temperature control, +4 °C, and rapid delivery)
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Which additional organs to sample: when and why to include liver, kidney, and heart, and how to avoid false positives caused by autolysis
- What analyses to request: culture, identification and quantification of Clostridia, α-toxin detection (ELISA or PCR), and histological examination
- How to interpret bacterial counts: clear threshold and decision framework combining CFU levels and time from death to sampling
- How to detect α-toxin: direct testing vs. testing after culture, ELISA vs. PCR, and the recommendation to test not only the most represented strain in the culture but a least 10 strains
- Special considerations in veal calves: why bacterial counts may not be reliable indicators in young animals
- Key rules: practical recommendations to maximize diagnosis accuracy
