Lameness is a common condition in sheep, having negative effects on growth rates, fertility, ease of mustering/yarding and interfering with transporting stock off farm. Most of the sheep lameness is due to either scald or footrot, both of which are likely to be caused by the same group of bacteria.
In scald, the area between the hooves become inflamed and swollen, becoming raw in more advanced cases. Footrot progresses from scald when the hoof tends to become separate from the soft tissues of the toes. When affected with scald or footrot, sheep show varying levels of lameness, often carry their head below their spine when walking, limping and grazing on their knees.
There are several risk factors that may lead to scald or footrot:
- Wet pasture conditions and mud.
- High stocking rates.
- Season (Autumn/Winter).
- Breed - Fine wool breeds such as merinos are particularly prone to Footrot. Coarse wool breeds tend to be more resistant.
- Bacterial strain on the property (some strains cause more severe disease than others).
Treatment can be achieved with the following methods:
- Move affected mobs to dry areas.
- Separate and treat affected animals.
- Regular foot baths with zinc sulphate 10% - this is safer than formalin and just as effective.
- Antibiotics – if having footrot issues, talk to your vet regarding the right antibiotic for your farm.
- Foot trimming – can be effective treatment in some cases, but if poorly done may slow healing. Foot trimming is ineffective in preventing footrot.
Prevention of footrot is better than attempting to cure it once it has started. There are several options available:
- Footvax – this is a vaccine that will protect most sheep against footrot, and also will help affected sheep heal more quickly. Talk to your vet if this product is suitable for your farm.
- Dry paddocks naturally prevent footrot, in winter however this can be unachievable.
- Breeding for resistance is a good long term strategy to reduce footrot in your flock.
- Eradication of severe strains of footrot bacteria on farm is achievable, but requires intensive management and good boundary/quarantine procedures.
If you have any questions regarding scald or footrot, we are more than happy to answer your questions in our Wairoa or Gisborne clinics.
Niklas Buddo BVSc (Dist.)