While cleaning up around the farm, it is a good time to take a look for possible chemical contaminants that could impact the health of your animals or the safety of the products they produce. Dairy farmers are aware and diligent about avoiding antibiotic residues, but a multitude of other chemicals exists that also could end up in animals and contaminate milk and meat. Environmental hazards, pesticides and herbicides as well as feed contamination issues should be kept on your chemical residue awareness radar screen. Recent accidental exposure of cattle to chemical hazards include accidental exposure to high doses of Rumensin®, anhydrous ammonia, benzene from gasoline, organophosphate insecticides and feed-grade antibiotics. In each of these cases, quick action prevented any food safety issues and limited animal health consequences. If a chemical contamination event on farm is discovered or suspected, immediately notify your veterinarian or the Department of Agriculture in your state.

Taking action to prevent accidental chemical contamination is not only vital to protect the health of your animals and the safety of the products they produce, but it is also important from an economic perspective. Under the best of circumstances, if a chemical contamination event were to occur and immediate action initiated, it may take weeks for a farm to regain market access for their products. This is due to the lengthy process of finding an approved laboratory with verified testing for uncommon residues and then waiting an appropriate length of time for chemicals to be removed (withdrawal times) from the body. As you are well aware, being unable to market milk or meat can have devastating financial consequences.

Here are some action points that you can initiate now to help reduce the risk of chemicals accidentally coming in contact with your cattle:

• Be diligent about keeping records on any chemical brought onto the farm. Records include what chemicals are on the farm, where they are used, when, how much and the withdrawal date for cattle or forage.

• Train employees on proper handling, usage and storage of all chemicals used on the farm.


• Keep all chemicals, such as pesticides, herbicides and rodenticides in their original container with their original label. A year from now you may not remember which chemical is the pink liquid in the blue spray bottle.

• Check around all buildings on the farm, as there are many old barns or storage sheds with bags of pesticides and herbicides, sprinklings of rodenticides on the ground or medicine cabinets with expired drugs forgotten in the back. Discard all unused out-dated pesticides and expired drugs according to label instructions.

• Any chemical to be discarded should be handled according to local, state and federal regulations.

• Make sure all chemicals and drugs are stored in a safe, secure place away from animals and their feed/water sources. Follow all storage and containment regulations.

• Make sure that fuel storage areas are properly located and spill containment barriers are in place.

• When using, moving or disposing of chemicals, do not use equipment, such as skid-steers, that are also used for feeding your cattle.

• Contact your feed mill and ask what they are doing to prevent chemical contamination of feedstuffs. Make sure they have routine quality control programs to reduce risk of contamination at the manufacturing level.

• Check purchased feed on delivery for color, odor, moisture, temperature and evidence of foreign material or bird, rodent or insect contamination. Make sure the feed delivered is what you ordered.

• While cleaning up the farm, it is a good idea to think about a contingency plan. If an inadvertent chemical contamination event was to occur, it is necessary to know who to contact and how milk and affected animals will be handled.

To maintain consumer confidence in dairy and meat products, dairy farmers must maintain a diligent awareness of chemicals on their farm. Take action now to reduce these risks. PD

References omitted due to space but are available upon request.

—Excerpts from Michigan Dairy Review, July 2010

Jamie Morrison
Michigan State University