Swatting at flies is a major aggravation but luckily for us, we can often shoe away these annoying arthropods before that painful bite. But what about cows and other livestock that only have a tail to defend themselves? Besides a quick pinch, stable flies actually have a huge effect on cattle costing the U.S. cattle industry more than $2.4 billion! How might you ask? Animals will often stop grazing and bunch together to minimize the number of bites they’re getting. Consequently, this can reduce milk production in dairy cows, decrease weight gain in beef cattle, and reduce feed efficiency.