Flies usually pose the greatest problem during the second half of the grazing season. If you are preparing to let your cattle back out on pasture, one option is insecticide ear tags.
A K-State veterinarian explains how they are beneficial.
Related:
Livestock producers should plan ahead for new fly control feed additives
USDA puts the brakes on mandatory RFID ear tags
R-Calf protests USDA’s cattle ID tags