Apart from entomologists, there are probably few people who would actively look for horse-flies. For their size, they have one of the most painful bites of any insect and the bite can result in a painful swelling. The genus Tabanidae is called deer-flies in the USA and horse-flies in Great Britain. They can cause problems in grazing animals by transmitting various diseases, including anthrax, and reducing milk output in dairy cattle. Blood-sucking is carried out only by the females and their mouth-parts have blade-like appendages that can cut through tough animal skin with ease. However, the flies themselves are not unattractive in appearance. Chrysops relictus is a stoutly-built insect, mostly shiny black but with variable yellow-orange bands around the upper part of the abdomen.