Consumer concern over chemical and biological residues in dairy and meat products is causing repercussions in the cattle industry.
In the United States, the federal agriculture department reported earlier this year that a study of higher-than-allowable levels of residues were caused mainly due to farmers failing to follow withdrawal times of veterinary medications.
The study showed that off the shelf or non-prescription drugs were the main source of residues and these were nearly always administered by farmers rather than veterinarians. The study also showed that most of the farmers at fault were also those who directly controlled the sale of their animals.
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Sold for slaughter
“For the first time, an undercover operation in the U.S. has uncovered criminal activity of knowingly selling medicated animals for slaughter for human food,” said Trevor Yurchak, of Alberta Agriculture.
“As a matter of practice, the withdrawal times set for each medication should be checked and followed carefully.”
Establishing accurate animal body weight is one of the most important aspects of dosage, suggests Alberta Agriculture. If not enough is applied, the results may not be as anticipated. Too much medication may result in radically different withdrawal times, leaving residues in meat and dairy products.
“Establishing withdrawal times is something that is extensively researched by pharmaceutical companies,” said Larry Frischke, a technical veterinarian from Ayerst Veterinary Laboratories.
“The information provided with drugs should be followed closely as it provides accurate information that the producer can use.”
Agriculture Canada recommends farmers strictly adhere to the manufacturers’ recommendations and destroy outdated material.
Antibiotics can sometimes break down into dangerous compounds if left after the expiration date, while some vaccines and other medicines must be refrigerated.
Medicated feeds should be stored separately from regular feed to avoid accidentally medicating lactating cows or cattle ready for slaughter. Government regulations for medicated feeds are available from Agriculture Canada.
“The implications are similar when dealing with weaning or finishing programs. Selling livestock without the proper withdrawal times from vaccines harms the industry,” said Yurchak.
Read the label
“It is up to each producer to read the medicine labels or consult with their veterinarian to ensure safe and proper use of all medications and vaccines.”
European withdrawal regulations are becoming so strict that veterinarians are facing a crisis. They say their ability to fight infectious diseases is declining as withdrawal times are increased. So strong has the consumer influence over food quality become in many European Union countries that only veterinarians are now licenced to prescribe and apply medications that produce residues.
“Off label use is something that is diminishing all the time but still is a problem out there … It will be better for livestock producers to be proactive and take care of the problems now than to find themselves with legislated solutions, that may not meet their needs, in the future,” said Frischke.