Three Conditions That Cost UK Sheep Farmers Millions Each Year
Footrot, flystrike, and clostridial disease are collectively responsible for enormous welfare costs and economic losses in sheep production across the UK and Ireland. Each is largely preventable. Yet all three remain stubbornly common, largely because prevention requires consistent management rather than a single intervention. This guide sets out what you need to know to protect your flock.
Footrot: Causes, Recognition and Control
What Causes Footrot
Footrot is caused by a synergistic infection between two anaerobic bacteria: Fusobacterium necrophorum and Dichelobacter nodosus. F. necrophorum is ubiquitous in soil and faeces, but D. nodosus — the organism that gives footrot its characteristic virulence and contagion — is spread between sheep via contaminated pasture and handling areas. Warm, wet conditions accelerate transmission significantly.
Recognising the Condition
Affected sheep are lame, often severely so. Examination of the foot reveals a foul-smelling necrotic lesion beginning at the skin-horn junction and undermining the hoof horn. In its early stages, the condition may be confused with foot scald (interdigital dermatitis caused by F. necrophorum alone), which does not undermine the horn. Distinguishing between the two matters for treatment decisions.
Treatment and the Five-Point Plan
The NADIS and AHDB five-point plan provides a structured approach to footrot control: identify and treat all lame sheep promptly using appropriate antibiotics (injectable oxytetracycline or penicillin); avoid footbathing as the sole treatment for true footrot; cull or vaccinate persistently lame animals; use vaccination (a licensed footrot vaccine is available in the UK) in high-prevalence flocks; and quarantine bought-in animals. Paring of the hoof to expose infected tissue is no longer recommended as first-line treatment.
Flystrike: A Welfare Emergency
The Lifecycle and Risk Factors
Flystrike (myiasis) occurs when blowflies — principally Lucilia sericata, the green bottle fly — lay eggs on sheep, typically in soiled, wet, or wounded areas. Larvae hatch within hours and begin digesting living tissue. A sheep that is not found and treated within two to three days of strike can die. The risk period in the UK runs broadly from April to October, peaking in warm, humid conditions.
Prevention Strategies
- Dagging (crutching) to remove soiled wool around the breech is the single most effective preventive measure
- Shearing reduces risk across the body during summer months
- Prompt treatment of wounds, footrot, and scour removes attractant sites
- Insect growth regulators applied as pour-ons or dips provide preventive protection for varying periods — consult your vet for product choice and withdrawal periods
- Regular inspection of the entire flock, at least daily during high-risk periods, is essential
Treating Struck Animals
Clip the wool widely around the affected area, remove all visible larvae, clean the wound, and apply a licensed wound treatment. Severely affected animals require veterinary attention and may need systemic antibiotic treatment and supportive care. Flystrike cases must be treated promptly; delay is a welfare offence under UK legislation.
Clostridial Disease in Sheep
The Key Clostridial Conditions
Several clostridial diseases pose significant risks to sheep. Pulpy kidney (Clostridium perfringens type D) strikes well-grown lambs, often the best in the flock, following dietary change. Lamb dysentery (C. perfringens type B) kills young lambs in their first few weeks. Braxy (C. septicum) follows ingestion of frosted or damaged pasture. Blackleg (C. chauvoei) causes sudden death in young stock. Black disease (C. novyi type B) is associated with liver fluke damage. All are acute and usually fatal once clinical signs appear.
Vaccination: The Essential Response
Multivalent clostridial vaccines covering seven or eight conditions (commonly called 7-in-1 or 8-in-1) are highly effective, safe, and cost considerably less than losing a single animal. The standard programme in the UK is as follows:
- Ewes: two primary doses four to six weeks apart, followed by annual boosters given three to four weeks before lambing
- Lambs: passive immunity from colostrum of vaccinated ewes protects for the first few weeks; active vaccination typically begins at six to twelve weeks with a two-dose primary course
- Bought-in animals with unknown history: always give a full primary course before relying on annual boosters
Liver Fluke: An Often Overlooked Factor
Fasciola hepatica is not technically a clostridial disease but is closely linked, as fluke damage creates the anaerobic liver conditions that allow C. novyi to proliferate and cause black disease. Fluke control is therefore an indirect component of clostridial disease prevention on wet, low-lying land. Strategic flukicide treatment — ideally guided by local risk mapping and liver fluke forecasts from NADIS — should be discussed with your vet and integrated with your overall health plan.
Practical Summary for Sheep Keepers
- Vaccinate all sheep against clostridial disease; time ewe boosters before lambing to protect lambs via colostrum
- Dag ewes before lambing and again before the fly season; shear promptly in summer
- Inspect the flock daily during April to October for signs of flystrike
- Treat lame sheep within three days of first noticing lameness; do not footbath and ignore
- Consider footrot vaccination in high-prevalence flocks
- Control liver fluke as part of a broader health strategy on at-risk ground
- Keep accurate flock health records; these are required under cross-compliance rules
Always work with a vet to create a flock health plan tailored to your land, stocking density, and local disease pressures. Prevention is invariably cheaper and kinder than treatment.