20 May 2026

Clostridial diseases on dairy calf to beef farms

One of the main challenges with clostridial disease is how fast it can strike. DairyBeef 500 Advisor, Gordon Peppard shares key advice – focusing on the risk factors and preventative options – for dairy-beef producers.

Clostridial diseases can lead to sudden, unexpected deaths in cattle and are a serious risk on Irish cattle farms. They are caused by Clostridia bacteria, which are commonly found in soil, slurry and the digestive tract of healthy animals. Although they are dangerous, they do not spread directly from animal to animal. Instead, cattle usually pick up infection from contaminated grass, feed, water or through wounds.

‘Clostridial disease’ is a general term that covers a number of serious conditions in cattle, including blackleg, tetanus, botulism, malignant oedema, pulpy kidney and black disease. In Irish beef systems, blackleg and tetanus are the most commonly seen threats in growing cattle. The biggest risk is in calves and young stock between three and twelve months of age, especially fast-growing animals at grass.

One of the main challenges with clostridial disease is how fast it can strike. In many cases, the first sign is finding a dead animal. Blackleg, for example, can kill strong, healthy animals within a few hours. Sometimes you may see warning signs beforehand, such as swelling in the muscle, lameness, fever or stiffness, but often it moves too quickly for these to be noticed in time.

Tetanus can occur after procedures such as castration or disbudding, especially where hygiene isn’t good. Affected animals often become stiff, have difficulty chewing and may have difficulty walking.

Botulism may lead to paralysis or sudden death and is often linked to contaminated silage or dead carcasses in feed.

Risk factors

Young cattle are more susceptible because their immunity is still developing and they are at higher risk when they’re under stress, such as after transport, mixing with animals from other farms, changes in diet, turnout, or housing.

Areas around feeders, gateways, and poached ground can also increase the chance of exposure to Clostridia in the soil. Fast-growing cattle grazing lush grass are particularly prone to blackleg.

Ground disturbance is another risk factor that is often overlooked. Clostridial bacteria can survive in soil for years in a dormant state. Jobs such as reseeding, drainage work, digging, installing water troughs, laying pipes or repairing tracks can bring these bacteria to the surface, where grazing cattle are more likely to pick them up.

Wet weather and freshly disturbed ground can greatly increase the risk of blackleg outbreaks. Cases are often seen after land improvement works or when cattle are turned onto newly reseeded paddocks.

Extra care is needed when calves are grazing fields that have recently had drainage or excavation work done. Try to avoid heavy poaching and, where possible, keep young stock off freshly disturbed ground.

Where major ground works are planned, it is important to make sure calves are fully vaccinated beforehand to help protect them.

Prevention

Prevention is much more effective than treatment, as once clinical signs appear, treatment is often unsuccessful due to the rapid progression of disease. Vaccination is the main way to control clostridial disease on Irish farms.

The recommended programme is two initial doses given four to six weeks apart, followed by a booster every year. Many farmers give the first dose at around six weeks of age with the second dose before turnout or during the first grazing season. Full protection is not immediate and only develops after the second dose.

Good management is just as important. Try to keep stress low around vaccination and avoid doing procedures like castration or disbudding at the same time. Always use clean needles and good hygiene during injections to help reduce the risk of tetanus. Feed and silage should also be checked regularly for dead birds, vermin as these can lead to botulism.

Clostridial vaccination is one of the most cost-effective ways to protect animals on calf-to-beef farms. With cattle values high, losing a thriving calf is a costly setback. A simple herd health plan, developed with your local vet, is the best way to keep animals protected and performing well throughout the grazing season.