In its early years, the USDA's focus was on regulating meat produce. More sophisticated railroad systems that included refrigerated cars meant the meat-packing industry could not only easily transport animals across state lines, but that it could also be a year-round operation. The department also focused on international transports of animals, which sometimes carried infectious diseases.
Out of these quality and safety concerns came numerous sub-agencies within the department, such as the Bureau of Animal Industry and the Bureau of Chemistry. The safety issues also prompted congressional action, such as the 1890 Meat Inspection Act (to monitor exported salted pork and bacon) and 1906 Food and Drug Act (enforced by the Bureau of Chemistry, which later become the Food and Drug Administration).