Antibiotic residues in milk and dairy beef are an important food safety issue. Dairy owners, managers and employees play a major role in food safety and in shaping consumers’ perceptions about food. Antibiotics in milk and beef may cause severe allergic reactions in persons with antibiotic sensitivity. In the dairy processing plant, antibiotics in milk can interfere with cheese and yogurt production.
According to the Pasteurized Milk Ordinance (PMO), all farm bulk tank milk and tanker truck milk must be tested for evidence of antibiotic residue prior to processing. Milk found with antibiotic residues is dumped with the dairy producer bearing the cost for the dumped milk. Further action may include suspension of the dairy producer’s Grade A permit, with reinstatement occurring only after “a representative sample of the producer’s milk, prior to commingling with other milk, is no longer positive for drug residue.”
Milk statistics
At the 2007 National Mastitis Council (NMC) Annual Meeting, NMC Residue Avoidance Committee members presented data that shows a decrease in antibiotic residues in milk over the past 10 years. According to the National Milk Drug Residue Data Base report for 2006, 0.038 percent of all samples taken were positive for a drug residue, down from 0.104 percent in 1996 (see Table 1*).
The National Milk Drug Residue Data Base is operated by an independent third party under contract with the Food and Drug Administration (FDA). Although the database was designed to promote maximum participation by the dairy industry to voluntarily report all testing results, it is important to recognize that the samples reported do not necessarily represent 100 percent of the milk supply from each state. Nevertheless, the downward trend is great news and is most likely related to successful teamwork among dairy owners, managers, employees, veterinarians, allied industry technical support, milk processors and university faculty.
Dairy beef statistics
It’s important for dairy producers and employees to remember that they’re also in the beef business, as dairy cows represent a major source of beef. In recent years, meat packers have implemented Hazard Analysis Critical Control Point plans and have focused their attention on the quality of cattle coming into the packing plant. Traditionally, the USDA’s Food Safety and Inspection Service (FSIS) has used ante-mortem (before death) findings as a basis for selecting cattle for residue testing. Common ante-mortem conditions associated with a high violation risk include:
1) evidence of recent surgery
2) slow, weak or dehydrated animals.
Certain post-mortem (after death) conditions associated with increased violation risk include:
1) mastitis
2) metritis
3) injection sites
4) pneumonia
5) peritonitis
6) abomasal disease
7) evidence of surgery
Only about 15 percent of violations result from ante-mortem findings, providing evidence that comprehensive post-mortem inspections are successful in the identification of violative residues.
According to a large East Coast meat packer that processes approximately 1,150 market dairy cattle daily, nearly 41,000 cattle were tested in 2006, resulting in 245 violative carcasses. In contrast, approximately 44,000 cattle were tested in 2000 at the same meat packing plant, resulting in 459 violative carcasses. The good news is that drug residues in carcasses are decreasing. Nevertheless, there is room for improvement.
Carcasses found to be positive on the initial test for drug residues are boned, frozen and retained pending further laboratory test results. Violators are notified within a few days of laboratory confirmation, and an explanation for the cause of the violation is obtained. Then the producer must provide evidence of immediate corrective action and long-term preventive measures. Next, the cost of the residue-condemned carcass is billed to the producer with the warning that repeat violations will result in market loss.
Educational resources
There are many tools available to dairy producers, veterinarians, herdsmen, allied industry personnel and Spanish-speaking dairy employees to help avoid antibiotic residues in milk and dairy beef.
It is important to remember that dairy owners, managers and employees play a major role in food safety, and in shaping consumers’ perceptions about food. PD
Table omitted but is available upon request to editor@progressivedairy.com.
