USE OF ANTIBIOTICS IN FOOD-PRODUCING ANIMALS
IN ONTARIO
The development of antibiotic agents has revolutionized animal care. While antibiotics have a primary and vital
role in the therapy of infectious diseases, antibiotics have been used at sub-therapeutic doses in livestock to
promote growth, increase feed efficiency and prevent disease.
The use of sub-therapeutic antibiotics also allows animals to be housed at high densities by reducing the
spread of disease. Sub-therapeutic use of antimicrobials increases feed efficiency, which allows animals to
achieve market weight more quickly.
The attitudes and actions of Ontario veterinarians related to antibiotic use in food-producing animals are not
well documented. As such, aspects of the CVO Survey were designed to gather information about the use of
antibiotics in food-producing animals in Ontario. Approximately 68% of respondents to the CVO Survey were
involved with dairy cattle, 42% with beef cattle, 28% with sheep/go