Proper antibiotic usage on the dairy is something that we all recognize as important.
However, it is also something that gets lost in the daily demands of the production environment. When we have animals that require medication, our primary focus is on the health of the animal.
We are also usually well tuned in to the risks associated with residues in milk, as the consequences of shipping a hot load are generally immediate and significant. But we tend to be less sensitive to tissue residue issues because the consequences of a carcass residue violation are generally less immediate.
Screening milk for antibiotics is an intensive process that involves every load of milk shipped, however many of the drugs we are screening for are focused on the beta lactams. Screening slaughter animals for tissue residue is a much broader process, involving other classes of anti-biotics as well as some nonantibiotic compounds such as flunixin and phenylbutazone.
The Food and Drug Administration (FDA) recently stepped up its surveillance of tissue residues in dairy animals. The agency has also begun publishing a list on its Web site of dairies and drug residues found.
This list is updated weekly, and since its inception in April 2009 it has grown to 100-plus pages of individual violations. The number of violations is relatively small compared to the number of dairy animals, both adult and veal calves, sent to slaughter during this time. Nonetheless, the list is still impressive to look at—and not in a good way.
The list makes it clear to people outside the dairy industry that at least a portion of the industry does not take its responsibility for preventing drug residues seriously. The impact of these poor decisions is potentially huge.
If you spend just a little time looking through the site, it is not hard to understand the perception that more restricted access to drugs is warranted. Many of the residue violations are the result of drugs that are approved for use in lactating animals, many are for drugs that are approved for use in dairy animals but not those of lactating age, and a few are for drugs that are prohibited from use in any dairy animal.
Most of these violations, I suspect, are the result of extra-label drug use (ELDU). ELDU is defined as any use that is not specified on the label. This includes use in different animal classes or species, different dosage levels, different dosage routes and different diseases than those listed. One reason these are defined as extra-label usages is that they potentially change the withdrawal times.
Extra-label drug use is not illegal.
However, when it occurs, there is a whole set of defined practices and procedures that must be implemented with your veterinarian's involvement.