Adult horsefly females are serious pests. They affect milk and meat production because the cattle they attack are heavily occupied in fending them off. A cow may lose more than a quarter of a liter of blood per day from horsefly bites. The flies, which are easily interrupted while feeding, may make numerous bites in order to finish a single meal. Horseflies readily move from one animal to another and are capable of transmitting diseases, such as anthrax and tularemia. Although the diseases they may carry primarily afflict animals, they can also occur in humans through contact with infected animals.