Facial eczema is a painful photosensitization disease of sheep caused by a fungal toxin. It affects millions of animals annually in affected regions and causes significant welfare harm.
Facial eczema causes genuine, severe suffering. Sheep with advanced disease experience liver damage, painful skin lesions, intense photosensitization, and weight loss. The behavioral signs — frantic shade seeking, head shaking, self-trauma — leave no doubt about the animal's distress. In heavily affected seasons, large proportions of a flock may be affected simultaneously. Prevention is far more effective than treatment and includes proactive zinc supplementation, spore monitoring, pasture management to reduce exposure, and long-term breeding for genetic resistance. Farmers who delay prevention until disease is visible have missed the critical intervention window.