Clostridium is a large genus containing gram-positive bacteria, some of them capable of causing diarrhoea in dogs. The two most frequent culprits are Clostridium difficile and Clostridium perfrigens. All Clostridium bacteria are anaerobic (they thrive where there is no oxygen) and capable of producing endospores.

Clostridium transmission

Clostridium bacteria are hard to clean away, because they produce endospores. The endospore is a dormant structure that allows the bacteria to survive even when subjected to really harsh conditions. Clostridium bacteria in the endospore form are resistant to adverse temperatures, starvation, ultraviolet and gamma radiation, and a lot of chemical disinfectants. The Clostridium bacterium is however prevented from reproducing while in this dormant state. When a dog ingests Clostridium bacteria, the bacteria can pass through the stomach since they are resilient to acid. Once they reach the colon, they will wake from the dormant state and start multiplying, thereby causing disease.  

Clostridium difficile in dogs

Clostridium difficile will normally not cause problems, but antibiotic treatment can make it possible for this bacterium to overgrow other bacteria in the gut of the dog and cause pseudomembranous colitis. Pseudomembranous colitis is a serious infection of the colon. If a dog develops pseudomembranous colitis, treatment with other antibiotics must be stopped and the veterinarian must start giving the dog antibiotics capable of attacking Clostridium difficile, e.g. metronidazole, vancomvcin, fusidic acid, or bacitracin. Clostridium difficile is resistant to most antibiotics and it can therefore thrive when common antibiotics are used to treat other dog diseases.

Clostridium perfrigens in dogs

Clostridium perfrigens is capable of causing a wide range of symptoms in dogs, from mild food poising till severe gangrene. Clostridium perfrigens is a part of the normal flora and it is often found in sick dogs without being the cause of the illness.

Certain strains of Clostridium perfrigens produce toxins which can cause food poisoning in dogs. Clostridium perfrigens can for instance be transmitted to the dog if it eats poorly cooked meat or poultry.  In the United States and the United Kingdom, Clostridium perfrigens is actually the third most common reason behind food-borne illness in humans.

If a dog eats contaminated food, the incubation time is normally 8-16 hours and the most commonly occurring symptoms are diarrhoea and stomach cramps. Vomiting and fever can occur, but it is not common. In otherwise healthy dogs, the symptoms will usually vanish within 24 hours without causing any long-lasting harm to the dog. It is however possible for this dog disease to develop into clostridial necrotizing enteritis, which can prove fatal for the dog. This risk is especially high if the dog has been infected with “Type C” strains of the bacterium, since this strain produces an especially strong and damaging toxin.

Studies on humans show that antibodies to Clostridium perfrigens toxin is very common, and many experts suggests that a majority of the population has suffered from Clostridium perfrigens food poisoning at some point; in most cases without seeking medic

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Clostridium in dogs
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