A contemporary map of Fasciola hepatica distribution in sheep and cattle in New South Wales.

Abstract

Fasciola hepatica is a global threat to livestock production, human health, and food security. Infection causes significant reductions in milk production and quality, feed conversion efficiency, wool quality, and reproductive performance. In New South Wales (NSW), Australia, data on the distribution of F. hepatica are more than 50 years out of date and lack species-specific insights for cattle and sheep. Accurate, up-to-date distribution data are essential for livestock producers to implement targeted control programs, for veterinarians to provide timely and effective treatment recommendations, and for researchers to identify emerging trends, such as those influenced by climate change. This study addresses this knowledge gap by using diagnostic samples submitted to the Elizabeth MacArthur Agricultural Institute (EMAI) between 2019 and 2023 to update the distribution of F. hepatica in cattle and sheep in NSW. Diagnostic records were extracted, cleaned, analysed, and geospatially mapped at the postcode level to reveal temporal and spatial trends by livestock species. Our findings suggest that F. hepatica hotspots in sheep are concentrated in the southeastern regions of NSW, whereas in cattle, hotspots extend along the coast. These results reinforce the existing dogma of F. hepatica distribution in NSW, providing evidence-based insights that are key to improved surveillance, refining precision parasite management, and mitigating the ongoing impacts of F. hepatica on animal health and production in NSW.