Veterinary pharmacologist warns that eggs from backyard chickens pose potential consumption problems
Whether raising chickens in your backyard as pets or as a source of fresh eggs, a Kansas State University pharmacologist says what you don't know about your chickens could hurt you or others.
Ronette Gehring, associate professor of veterinary pharmacology at the university's College of Veterinary Medicine and regional director of the Midwest branch of the Food Animal Residue Avoidance Databank, or FARAD, says that owners need to be aware of potential drug residues in eggs from backyard chickens that might be or have been on medication.
"These animals get sick from time to time," Gehring said. "They may get injured and need antibiotic treatment or pain medications. Foot infections are quite common, while sometimes the animals may need treatment for external or internal parasites."
The danger is that residues from the medications remain in eggs for various lengths of time.
"Owners must be aware that any drug they administer will result in residues in the eggs," Gehring said. "It's important that if owners buy medications over the counter to treat their flock, they closely follow the directions on the label. This includes only using the drug if it is specifically labeled for chickens laying eggs and only for the diseases listed on the label, at the exact dose, dosing interval and duration of treatment given in the instructions."
The Food Animal Residue Avoidance Databank keeps information about medications and the withdrawal time for different animals. Gerhing said backyard chicken owners need to be very attentive when giving the animals any medications.
"If all these instructions are followed closely, there will be a withdrawal time given on the label, which is the time for which the eggs must not be consumed after the last dose," she said. "Any deviation from the label instructions is considered extra-label and is illegal unless it is prescribed by a veterinarian within a valid veterinarian-client-patient relationship. There are very few drugs specifically labeled for backyard chickens. Most are formulated for large commercial operations, so many treatments for backyard flocks will be extra-label, requiring a prescription from a veterinarian."
The Food Animal Residue Avoidance Databank only gives extra-label drug use advice to veterinarians. Exclusively for food animal species, the databank is a congressionally mandated risk-management program supported by the U.S. Department of Agriculture and maintained by a consortium of universities, including Kansas State University; University of California, Davis; University of Florida; and North Carolina State University.
"Another problem owners need to be aware of is exposure of their chickens to chemicals and toxins in the home environment," Gehring said. "For example, an owner may have wasps in the backyard and spray them with pesticides. The chickens might eat the wasps, which can cause residues in the eggs. Other environmental, accidental exposures can occur, such as herbicides sprayed for weed control. If an owner suspects an environmental exposure, then they can call FARAD themselves, but it's important to know which chemicals the chickens may have been exposed to."
Owners are encouraged to visit with their veterinarians. More information is available at the Food Animal Residue Avoidance Databank website at www.farad.org.