While on antibiotics, a cow’s milk must be diverted to a separate container and properly disposed of for a regulated period of time. Milk from a cow who has been given antibiotics can only start re-entering our food supply after a withdrawal period longer than the time it takes the antibiotics to be fully out of their system. Health Canada studies and publishes the “withdrawal period” for each antibiotic that is licensed for use in dairy cattle.
All milk is tested for antibiotic residues before it is shipped to be bottled.
Every truckload of milk is tested before being unloaded at the processing plant. If antibiotics are found, the entire load is discarded and the farmer who contaminated the load is heavily penalized.