Foot rot or CODD: Which is which and why does it matter?
Lameness in sheep is an ongoing issue that many of our farmers face, and with changing guidance and emerging diseases it can be difficult to know how to best approach the problem! The most common causes of lameness are scald, Foot rot and Contagious Ovine Digital Dermatitis (CODD), and it is important to distinguish which are present in your flock so that appropriate treatment steps can be taken.
Scald
- Pink to red discolouration of the skin between the claws of the hoof
- May have a white or grey pasty material between the claws and a strong smell
Foot rot
Foot rot is a progression on from scald and is caused by the same species of bacteria.
- The lesion is still based between the claws of the hoof but with grey pus and a foul smell
- The horn of the hoof can start to detach and peel off, beginning in the interdigital space
CODD
CODD was first identified in the UK in 1997 but by 2017 it was estimated that 50% of UK flocks were affected. It is caused by a different species of bacteria to the species that is involved in scald and foot rot, and therefore requires different antibiotics to treat it.
- The initial lesion occurs at the top of the hoof, at the junction between the horn and the haired skin, rather than between the claws
- Hair loss is seen and red, ulcerated lesions
- The horn of the hoof starts to detach, starting from the top rather than the interdigital space. The whole hoof capsule can fall off
Treatment
| Antibiotic spray | Antibiotic injection | Foot bathing | Foot trimming | Footvax | Isolate | |
| Scald | Yes | No | Yes | No | Yes | Isolate affected animals or footbath the whole group and move to pasture that hasn’t been grazed for 2 weeks |
| Foot rot | Yes | Yes (*see below) | No | No | Yes | Separate affected animals to reduce spread |
| CODD | Yes | Yes (*see below) | No | No | Doesn’t provide immunity against CODD but can reduce disease where mixed infections are present | Bacteria can survive for a long time in the environment and on hands and equipment, so affected animals should be isolated and equipment and hands should be disinfected |
Correct and prompt treatment for lame sheep is very important to improve success rates. Different antibiotic injections are recommended for Foot rot and CODD and therefore it is important to know which are causing problems in your flock, or whether there is a mixture of different infections. While routine foot trimming used to be recommended, new research has shown that it can delay healing in lame sheep and is a very effective way of transmitting bacteria between animals! Additionally, foot bathing is effective at reducing bacterial levels on feet and can help to prevent scald and Foot rot, but the products used are irritant and can damage the exposed sensitive tissues in Foot rot and CODD cases. For all causes of lameness it is recommended to separate affected animals to minimise spread, and to cull repeat or chronic cases.
More information: AHDB’s 5 point plan for lameness Reducing lameness in sheep | AHDB
