Zoetis Inc. discovers, develops, manufactures, and commercializes animal health medicines, vaccines, and diagnostic products in the United States and internationally. It commercializes products primarily across species, including livestock, such as cattle, swine, poultry, fish, and sheep; and companion animals comprising dogs, cats, and horses. The company also offers vaccines, which are biological preparations to prevent diseases of the respiratory, gastrointestinal, and reproductive tracts or induce a specific immune response; anti-infectives that prevent, kill, or slow the growth of bacteria, fungi, or protozoa; and parasiticides that prevent or eliminate external and internal parasites, which include fleas, ticks, and worms.