A 'green' toolbox: non-chemotherapeutic approaches for gastrointestinal nematode control in ruminants.

Grazing ruminants are commonly infected with gastrointestinal nematodes, and their negative impacts on animal health, welfare and production are intensified by increasing anthelmintic drug resistance. The goal of reducing anthelmintic use while preserving effective parasite control has motivated research on non-chemotherapeutic interventions, including those relevant to 'green'/organic ruminant production systems. However, 'green' control strategies are at varying levels of development, and an updated overview of the fragmented evidence is timely before they can be integrated with current parasite management. Here, we highlight recent scientific progress of selected non-chemotherapeutic tools for gastrointestinal nematode control in ruminants, existing knowledge gaps, and how novel research approaches and new technologies are contributing to their testing, further development and on-farm implementation, while advancing our understanding of host-parasite-environment interactions.