The first vaccines that can prevent metritis, one of the most common cattle diseases, has been developed by researchers. The infection not only harms animals and farmers’ profits, but also drives more systemic antibiotic use on dairy farms than any other disease. The new vaccines prevent metritis infection of the uterus from taking hold and reduce symptoms when it does, a prospect that could save the United States billions of dollars a year and help curb the growing epidemic of antibiotic resistance.