External parasites including flies, lice and mange mites cause significant welfare problems in cattle, particularly during summer months when fly populations peak.
External parasite control is fundamental to cattle welfare, particularly for housed animals and during peak fly seasons. The welfare harms caused by parasites range from the irritation of fly worry — which causes cattle to bunch, reduced grazing time and elevated stress — to serious conditions like New Forest eye causing blindness, or warble fly migration causing chronic subcutaneous pain. Integrated parasite management combining environmental control, strategic treatment and monitoring provides the best welfare outcomes while minimizing chemical use and resistance development. Regular monitoring allows early intervention before welfare problems become severe.