The National Conference on Interstate Milk Shipments (NCIMS) pilot project on tetracyclines found a total of six positives on the 304,289 samples tested between October 1, 2017 and September 30, 2018. That’s a violation rate of 0.00197%.
The pilot project was initiated on July 1, 2017 to look for tetracycline residues because milk plants had not been routinely testing for the drug prior to that time. The pilot project required milk plants to look at “not less than 1 in 15 bulk milk tankers” coming through their unloading bays each day.
The tests screen for oxytetracycline, tetracycline and chlortetracycline. The tolerance level for tetracyclines is 300 parts per billion. Hoof trimmers use tetracyclines to treat digital dermatitis.
The testing period that was reported in the most recent National Milk Drug Residue Database was for 2018 fiscal year. Just one tetracycline sample tested positive from July 1, 2017 through Sept. 30, 2017 out of the 106,934 samples tested during that three-month period.
What happens now with tetracycline testing remains to be seen. It’s likely the Food and Drug Administration will make recommendations on whether testing be expanded, remain at one tanker out of 15, or discontinue testing at this spring’s NCIMS meeting in St. Louis, says Jamie Jonker, Vice President, Sustainability & Scientific Affairs, for the National Milk Producers Federation.
“Although the tetracycline pilot did end January 1, 2019, I wonder if there may be more business-to-business required testing as a result of the pilot [program]. For that, only time will tell,” he says.
The National Milk Drug Residue Database reports the number of total drug residue violations in fiscal year 2018 were the lowest since 2015, with just 584 samples reporting positive out of the 4.2 million tested. Of those positives, 578 were beta lactam violations with the remaining six being tetracycline.
No violative residues were found for sulfonamides or sulfamethazine.
Of the residues, 364 were found in bulk milk pick up tankers (0.010%), 210 in producer milk (0.059%), 4 in pasteurized fluid milk and milk products (0.012%) and six from other sources. None of these positive samples entered the food supply, with slightly more than 16 million pounds of milk discarded with positive residues.