Last month, the U.S. Food and Drug Administration (FDA) began its bulk tank milk screening study for anti-biotic residues.
The original plan was to start this process last November. However, FDA made the decision to delay when it became evident that the initial strategy was going to seriously disrupt milk shipments.
FDA had intended to use a "sample/enforcement" strategy in which known farms would be sampled and, if a sample was positive, the agency would follow up with enforcement. This meant that not only would the involved farm be subjected to further attention, but any product that was made using milk that contained positive residues could be subject to recall.
From the processor’s perspective, this would put millions of dollars of product at risk. The industry’s first thought was to simply dump the tested milk so there would be no risk of finding out later that there was a problem.
However, it rapidly became evident that, particularly on larger dairies and depending on how screening was carried out, there would be a huge amount of milk potentially at risk. To FDA’s credit, it considered this feedback and decided that it could accomplish its goal without having to know the origin of each sample.
The current screening strategy will result in completely "blind" samples. From this survey, FDA will be able to get an idea of the extent to which positive residues can be found in the milk supply.
This process began as a result of FDA’s review of tissue residues occurring in animals at slaughter. Overall, the number of animals that are slaughtered each year and that have positive tissue residues is less than 1%. While roughly 7.7% of the cattle slaughtered in the U.S. are adult dairy cattle, they are responsible for 67% of the positives.
Not surprisingly, this led FDA to wonder about the levels of residues that might be occurring in the milk. The agency intends to take approximately 900 samples from dairies that are known to have shipped cattle with positive tissue residues. It will take another 900 random samples. Sampling will be done throughout the year.
Screening will be done for 30 different compounds. Most are antibiotics, but both Flunixin and Tripelennamine will also be screened for. Many of these drugs have established "safe levels." However, the methods that will be used to initially screen samples will detect at levels lower than these.
Now would be a good time to review your practices for managing sick animals. An updated copy of
the Milk and Dairy Beef Drug Residue Prevention Manual was recently released. Get your veterinarian involved and use this handbook as a guide to review your program.
We owe it to our industry as well as the customers who trust our products are safe to make sure the results of this survey strengthen that trust.
MARK WUSTENBERG, DVM, works with Tillamook County Creamery Association in Tillamook, Ore.
You can contact him at firstname.lastname@example.org.