Study Tracks Facial Eczema Impact on New Zealand Sheep Farms

A new study by Beef + Lamb New Zealand is examining the impact of facial eczema on sheep farms throughout the country, utilizing fresh sheep manure to gather crucial data. The research, led by animal health principal scientist Cara Brosnahan from Wellington, is now in its third and final season.

During the second season, researchers detected low levels of facial eczema spores on four sheep farms in Otago. The first season revealed similar findings, with spores identified on one sheep farm in Southland. Grazing livestock, apart from horses, can contract this disease by ingesting toxic fungal spores commonly found in pasture, particularly ryegrass.

Farmers are informed when spores are found in their manure samples and are encouraged to continue submitting samples to monitor spore levels. If the numbers rise, they are advised to consult a veterinarian. The spores are environmental fungi that can proliferate under specific conditions, often going unnoticed by livestock until they reach harmful levels.

Dr. Brosnahan emphasized that even if livestock do not show immediate clinical symptoms, hidden signs can include decreased productivity or increased empty rates during pregnancy scanning. Clinical symptoms of the disease have been reported from regions ranging from Northland to the West Coast. Alarmingly, over half of the manure samples provided by farmers in the northern South Island exhibited clinical signs of facial eczema.

The study aims to establish connections between farm elevation, pasture height, and neighboring spore counts in relation to the risk of facial eczema. The final season is critical for confirming these relationships, and participation remains free and straightforward. Farmers collect sheep manure samples every two weeks from October to May, with Beef + Lamb supplying the kits and covering postage costs. In return for their participation, farmers receive results to better understand their risks, a $40 subsidy for fecal egg counts, and the opportunity to be selected for monthly fecal egg counts and larval culture testing.

Farmers play a vital role in mitigating the economic impact of this disease, which costs the agricultural sector more than $330 million annually. Dr. Brosnahan stressed the importance of increased participation, especially from farmers who have not yet detected facial eczema on their properties. “Those results help build our understanding of this devastating disease,” she stated.

Facial eczema causes liver damage in affected livestock, leading to decreased fertility, weight loss, reduced milk production, photosensitivity, sunburn, and, in severe cases, death. “There’s no cure, so proactive management is essential,” Dr. Brosnahan added.

Graham Evans, a sheep farmer from Barr Falls Farm in the Catlins, actively participates in the study. He collects and sends fresh manure samples to researchers, dedicating approximately 30 minutes to the process every two weeks. To date, no spores have been found on his property, but he acknowledges the inevitability of the disease spreading southward. “It doesn’t matter whether you believe in climate change or not. It’s going to happen,” he warned.

Evans hopes that more farmers in southern regions will contribute to the study, highlighting the differing conditions between sheep farming environments from the Catlins to Central Otago. His involvement is driven by a desire to assist future generations of farmers in understanding and managing this significant health risk to livestock.