Why some dairy cows naturally fend off the horn fly

A recent study found that some Holstein dairy cattle naturally fend off the horn fly. These findings could help organic milk producers whose dairy cows are pasture-raised and are not exposed to synthetic pesticides or antibiotics. Penn State’s College of Agricultural Sciences discovered that some Holstein dairy cattle, particularly those with white coat coloration, naturally fend off the horn fly, a parasitic insect that can cause stress and disease in grazing cattle. Hundreds of millions i