Buckeye Dairy News: Volume 2 Issue 4
Wet Conditions Increase the Chances for Pesticide-Contaminated Forages
The use of organochlorine pesticides such as DDT, aldrin, dieldrin, heptachlor, lindane, etc., has been banned for approximately 30 years. Therefore, they should not present a risk of actionable residues in milk or meat products. Unfortunately, the latter statement is not quite true. Each year there are a few instances of unsuspected contamination, and these usually occur following periods of wet weather. By understanding the conditions that contribute to the contamination of forages, the likelihood of an expensive incident can be reduced.
Organochlorine pesticides were the first formulations to receive widespread use beginning with the production of DDT in the 1930's. Large quantities of these materials were used before they were discovered to be persistent in the environment and accumulate up the food chain. As the undesired side effects of these chemicals became known, tolerances were established to limit exposures to human foods, and ultimately in the late 1960's and early 1970's, organochlorine pesticides were banned or severely restricted in their use. So how can they still be a problem today?
The foremost characteristic of this class of chemicals is that they are extremely stable compounds and readily do not degrade. Likewise, they remain persistent in the soils where they were applied. Organochlorine pesticides are relatively insoluble in water. As a result, they do not leach downward through the soils but remain near the soil surface or within the plow zone. They may migrate with surface water, but it is usually a case where the pesticides move attached to soil particles or organic materials. These chemicals are also lipophilic, which means that they will associate with fats and oils. Thus, when consumed by animals they will accumulate in adipose tissues and will be excreted in milk fat if the animal is lactating. With the stringent tolerances that are in place for residues in milk and meat, only small amounts of these pesticides need be consumed to result in exclusion from the market.
Where dairy production is concerned, as long as these pesticides remain bound in the soil, there should not be a problem. The problem occurs when there is a route of transfer to the cattle. Fortunately, these pesticides do not translocate through the roots of plants into the forage or seed portions of plants.However, two routes of transfer have been identified. The first is fairly obvious. If animals consume sufficient quantities of contaminated soil, they will accumulate organochlorine pesticides. Whether this will become a problem depends on the amount of soil consumed and the concentration of the pesticide in that soil. Studies have been conducted that have shown that cows on pasture will consume up to 4.5 pounds of soil per day. Lesser amounts were consumed when pastures were lush, because grazing was higher on the plants, with less ground contact and with less soil material splashed on to the forage. Certainly, with a sufficient pesticide concentration in soil, consumption can result in undesirable residue concentrations in milk and meat, yet it is rare.
Maintaining Quality Grain in Storage
If you had $15,000 to $30,000 in cash sitting in a grain bin, would you check it often? You know you would. So why not check your grain that is worth that much?
When you store wheat, oats, rye, barley, grain sorghum, shelled corn, or any other grain on your farm for extended periods, you must take steps to preserve its quality and prevent economic loss from insect and mold damage.
Properly managing grain in your storage bins, it is important to maintain quality. Factors that can cause grain to go out of condition are:
1. Presence of insects
2. The amount of fines and foreign-material left in the stored grain during filling of the storage
3. Initial quality of grain going into storage
4. Grain moisture content
The market or feed value of infested grain may be substantially reduced if the number of insect-damaged kernels is sufficient to lower the grade of the grain to be designated infested on the grade certificate. Producers often have to pay discounts to buyers finding live insects in their purchased grain. And some grain dealers may refuse to accept heavily infested grain that might contaminate their storage facilities.
Heavy infestation of insects and mold greatly reduces the feed value of grain. Molds can produce toxins that can cause abortions, low fertility, poor production and poor growth rate.
Insects in farm-stored grain will also affect its eligibility in the Grain Reserve Program for farmers. Conditioning of the storage structure and that of the stored grain are factors that must be considered by the Farm Service Agency commodity inspectors when determining eligibility for a farm-storage loan. When a loan is approved, the storer, who is often the producer, is responsible for any loss in quantity or quality of the commodity caused by insect and mold infestation or rodent damage during storage.
Grain temperature must be controlled to limit moisture movement through the grain. Lower grain temperature decreases molds and insect activity and increases safe storage times. More grain goes out of condition due to temperatures not being controlled than for any other reason.
As spring and summer temperatures warm up, it is very important to monitor the temperature and moisture in the stored grain. Temperatures can increase quite rapidly and that will increase insect activity. The grain in storage needs to be monitored often to prevent temperature and moisture increases and increase in insect activity.
There are insect traps available that can be inserted into the grain mass to monitor insect activity. If you value your money in the bin, keep a watch on the grain for insect activity, temperature rise, and excess moisture.?