This is most prevalent in the spring and autumn period of flush clover growth, and the incidence can be reduced if there is mature feed available at these times. If a serious outbreak occurs it is often best to put the herd on supplementary hay and silage, plus limited grass until the pasture matures. This is often not possible and the spraying of pastures with cheap oils is necessary. Penicillin can also be used but this has disadvantages where the incidence is frequent and high. However, proper grazing management and the avoidance of clover dominance in the swards should always be the main consideration.