Antibiotic use in the livestock industry greatly varies on the animal industry and the farm. Much of the controversy is over the use of subtherapeutic levels where antibiotics are not used for treating sick animals, but instead routinely given at low doses.
However, subtherapeutic doses can prevent subclinical diseases, like necrotic enteritis in poultry. Some human food-borne pathogens are reduced in poultry as well, like Campylobacter bacteria, which can cause illness if the meat is not prepared properly.
Antibiotics also treat mastitis, a common udder inflammation in dairy cows, which substantially reduces milk quality in addition to being painful for the cow. As long as milk is pasteurized, antibiotic-resistant strains would not likely be a human health risk because pasteurization kills both susceptible and resistant strains. In organic and antibiotic-free industries, however, if antibiotics are used even to treat sick animals, the meat can no longer be considered organic or antibiotic free.
For beef and pork, on the other hand, antibiotics improve weight gain and food utilization by the animal. The ban of antibiotics for growth promotion would significantly impact the income for farmers or raise the price of animal products.
Therefore, both the microbiological and agricultural perspectives on the use of antibiotics in animals should be considered when finding sustainable solutions to the problem of rising antibiotic-resistant strains of bacteria.
Ask Ms. Scientist is written by Corinne Thornton. If you have a burning science question you want her to answer, email it to
science@dailycardinal.com.
