Common Causes of Lameness in Sheep
Type Media Article
By Sean Mannion Teagasc Adviser Galway/Clare Regional Unit
Every sheep farmer has lame sheep. Lameness is one of the most common and persistent disease problems in Irish sheep flocks. Lameness creates a major cost on many farms in terms of time and money spent on products to treat and prevent the condition as well as the associated production loss. Apart from being an animal welfare issue, lameness has adverse effects on production, fertility and longevity.
One must first establish the cause of the disease before attempting to control or treat lameness. The different lameness conditions can be easily misdiagnosed. Accurate diagnosis can be made based on the clinical examination of a number of sheep and based on key symptoms of the different causes;
Scald - This occurs between the hooves and is usually red/pink and moist with the loss of hair. It comes from inflammation of the skin between the digits. Antibiotic sprays or footbaths are usually sufficient. With Scald there is no smell and no involvement of the hoof.
Footrot - This is a hoof disease that generally starts between digits but develops to an under run hoof and it also has a distinctive smell. Rotting in the hoof is also another sign. Footrot is a sheep to sheep disease and control and prevention must focus on the whole flock. It is particularly transmissible when sheep are confined in a small area e.g. during housing periods, in handling yards, contaminated bedding or access routes. To treat individual cases of Footrot, injectable antibiotics should be used. There is a vaccine available to reduce the incidence of the disease
Shelly Hoof - The wall of the hoof detaches and debris and soil enter the space, as result abscesses usually develop. Treatment is only necessary if lame. Careful paring may be required to release debris and soil.
CODD (Contagious Ovine Digital Dermatitis) - This type of lameness starts at the coronary band (where the hoof and the hair meet). It usually spreads rapidly to under run the hoof wall. It is usually the outside wall of the hoof that is affected. There is no foul smell with this type. It bleeds easily and as the name suggests it's contagious and can affect 30% - 50% in a short time. It is important to note that a sheep can be affected with both footrot and CODD at the same time. Tetracycline antibiotics and routine footbaths are not effective at controlling CODD. Treatment with specific antibiotics and antibiotic spray together with antibiotic footbath solution is required. A veterinary diagnosis is essential for the correct treatment of CODD.
At any one time on the farm, the aim is to keep the number of lame sheep below 5%.
Key Points to Remember to Control Lameness:
- Treat - it is essential that all lame sheep are caught, lameness identified and treated effectively. The good sheep farmer will have a keen eye and observe the flock closely for signs of lameness.
- Separate - Separate lame sheep from the rest of the flock so that healthy sheep are not infected.
- Cull - Cull persistent offenders. Therefore records and identification marks are important so to identify these sheep easily and to avoid retreatment on multiple occasions.
- Quarantine - Quarantine all incoming sheep should be quarantined for 28 days to avoid the introduction of a different strain of Footrot or CODD. Sheep should be examined thoroughly while in quarantine. Lame sheep should never, ever be added to the flock
- Vaccinate - use of vaccination has been shown to reduce footrot significantly by protecting individual sheep and reducing the challenge on farm.
'Lameness Control' is one of the main tasks being addressed for lowland flocks under the Sheep Welfare Scheme. Farmers who have chosen this task must:
- Carry out a minimum of 5 lameness examinations per year and update their scheme action record book.
- Farmers must record the % of lame sheep, identify cause and treat lame sheep accordingly.
- As a guide, photos of the main causes of lameness as outlined above are included in the action record book for your assistance.
- Establish the occurrence of lameness in the flock
- Establish the cause of lameness in the flock
- Adopt the control measures above as appropriate to reduce lameness in your flock.