Mud fever, taxonomically known as pastern dermatitis, encompasses a whole range of diseases that cause irritations and dermatitis to the lower limbs of horses. It is frequently caused by a bacterium known as Dermatophilus congolensis, which thrives in wet and muddy conditions. This infection is known to occasionally stay dormant in the skin and only becomes active when the skin is weakened, in this case by prolonged exposure to moisture in mud. In these instances the spores germinate and produce hyphae that permeate the skin and spread throughout the body, often resulting in an acute inflammatory reaction.
Signs of mud fever:
- Matted areas of hair that have scabs.
- A thick discharge that is usually a creamy white, yellow or greenish in colour.
- Deep fissures in the skin or ‘cracked heels’.
- Limbs that are swollen, hot and painful.
- Occasional lameness.
- Lethargy, loss of appetite and depression.