Clostridial diseases are a group of diseases caused by the bacteria, Clostridium. These diseases affect cattle and sheep however, goats are also susceptible to disease. If a preventative program is not in place, individual properties can suffer considerable losses as the diseases usually end in death.
The causative bacterium is highly resistant being able to live in the environment for long periods of time, normally found in the soil or faeces. The bacterial spores may also occur naturally in the gastrointestinal tract or in the tissue of healthy animals.
The bacteria may live in the animal with no consequences, are then excreted in the manure and able to infect the surrounding environment. The bacteria in the gut will only cause problems when factors within the animal are suitable. The bacterium in the environment relies on broken skin (cuts and abrasions) or ingestion to enter the body, where favorable conditions in the animal’s body allow for the bacteria to multiple and produce fatal toxins. Clostridial organisms are, for the most part, normal flora of cattle and only become problematic with dietary stress, injury, changes in management, parasitism or other unusual circumstances that set up a favorable growth environment and result in production of fatal toxins. In general, clostridial diseases carry a very poor prognosis and the first sign of illness may be death. Some of the diseases caused by the bacteria are: Black disease; Blackleg; Botulism; Malignant oedema; Pulpy kidney (enterotoxaemia); Tetanus
Table1: Diseases attributed to clostridial bacteria
| Clostridial type
||Lock jaw, spastic paralysis
|C. novyi type B
||Black disease, malignant edema, gas gangrene
|C. perfringens type A
||Jejunal hemorrhage syndrome, abomasal ulcers and tympany, gas gangrene, sudden death
|C. perfringens type C
|C. perfringens type D
||Malignant edema, gas gangrene, enterotoxemia
||Blackleg, black quarter, malignant edema
||Enterotoxemia (sudden death syndrome), malignant edema
||Red water disease
Source: Managing Clostrial diseases
Factors that can lead to disease:
- Changes in nutrition, Changes from poor to good food: animals that are placed on lush green pastures after the winter or are suddenly fed rich feeds, such as maize, are at risk.
- Lack of care with procedures such as castration, tail docking, wound cleaning and treatment as well as helping animals to lamb or calve can lead to disease.
- Stress: any abnormal situation, such as sheep lambing in small camps, deworming is dangerous.
- Animals nibbling on carcasses or old bones, or drinking water, or eating feed contaminated by dead animals.
- A wound or a procedure not performed correctly (e.g. castration)
- feeding chicken litter.
Signs in live animals:
- Animals that suffer from these diseases are usually found dead without any visible signs.
- Some animals may show signs of stomach pain, depression, watery grey or bloody diarrhoea, weakness and even nervous signs such as convulsion (fits) or paralysis.
- Mostly young animals are affected, but older animals may also become sick and die.
- The part of the body affected may be very swollen. When the area is touched it feels spongy and is filled with gas bubbles.
- Lameness, depression and swellings as a result of fluid under the skin (oedema).
- Tetanus: The disease develops within 1 to 3 weeks after a wound or a procedure not performed correctly. The third eyelid moves across the eye. The animal becomes increasingly stiff and walks with difficulty. This leads to paralysis, with spasms of the legs, head and neck. Death occurs within 1 to 3 days.
- Animals do not have a temperature and may be partially or totally paralysed.
- The tongue may hang out of the mouth but the animals will still try to eat. Because they cannot swallow, water given carelessly in the mouth may get into the lungs.
- Animals die of pneumonia or they stop breathing because of the paralysis.
- Sheep may have an arched back, with a drooping head and neck
Signs in dead animals:
- Gas-filled red intestines (note that animals that have been dead for a while may show similar signs).
- Soft, pale kidneys (pulpy kidney).
- Parts of the body are swollen.
- Affected muscle has a streaky dark red, greyish-red to yellow and black colour and is filled with gas bubbles.
- Infected or neglected wounds
Diseases with similar signs
Clostridial diseases can be confused with one another, as well as with anthrax, toxic plant poisoning, snakebites, poisoning with chemicals, rabies, three-day stiff sickness, redwater, heartwater, infection of the brain, tick paralysis, twin lamb disease (domsiekte) and tapeworm cysts in the brain.
Treatment of clostridial diseases is generally not economically viable. High treatment costs associated with the large amount of antibiotics required, rapid onset of disease and the low recovery rate offers little value. Therefore, it is important to have an effective prevention strategy in place to protect your herd or flock. Because these diseases start suddenly with few signs, treatment is nearly always too late to cure the animal.
Supportive treatment and antibiotics, such as penicillin, may help in early cases. Treatment of tetanus and botulism is difficult, with poor results. In the early stages, treatment with a substance called antitoxin against the disease may save the animal, but it has to be given as soon as signs are noticed and is not always at hand at times when it may be needed.
Prevention and control
- Care with change in feed, good management, vaccination.
- Good wound management
- Phosphorus supplementation in licks
- Clean feed and water
- Removing carcasses from the veld
Prevention is achieved through immunity, developed through vaccination. There are a number of commercially available vaccines which contain 2, 4, 7 or 8-way combinations of clostridial organisms that offer good protection against these clostridial diseases except botulism. They should be appropriately timed to provide maximum protection at the age of susceptibility. Animals generally develop a level of immunity 10 days after their second dose of vaccine.Factors to consider when vaccinating include:
- Handle and store vaccine according to label directions.
- Ensure needles and vaccination equipment is clean.
- Vaccination is to be given subcutaneously.
- Calves should be vaccinated from 6 weeks of age and given a booster 4-6 weeks later to ensure sufficient immunity.
- Stock that have not been vaccinated previously or vaccination history is unknown should be given two doses 4 to 6 weeks apart.
- An annual booster should be given to animals to ensure continued immunity.
- Annual boosters should be administered 4 weeks prior to calving or lambing to ensure that immunity is passed onto the new born calf via colostrum.
- Immunity against pulpy kidney only lasts up to 3 months.
- Young animals, up to 2 years of age may need to be revaccinated.
- The requirement of boosters for pulpy kidney can depend on seasonal conditions and if there is likely to be a change in diet such as a grain feeding.
- Boosters should be given before feedlotting lambs.
- Consultation with your local vet or product advisor is recommended before commencing a vaccination program.
- To aid in the efficacy of the vaccine, hygienic practices should be used when castrating and dehorning by ensuring equipment used is clean and yard conditions prevent mud or faecal material contaminating the fresh wounds.
- Wound dressings such as antiseptic sprays will help prevent infection.