Early freezes and record high rainfall has led to a late and wet corn harvest for producers this year. Not only did producers have a hard time getting into the fields, but corn moisture levels were higher than annual averages, increasing the risk of mold and mycotoxins in harvested and stored crops.

According to the USDA, as of November 1, 2009, only 25 percent of the national corn crop had been harvested, compared to the five-year average of 71 percent. While harvest numbers are increasing, the result is an intense and fast 2009 harvest.

Cold and wet growing seasons, such as experienced this fall, often delay grain maturity and can potentially lead to an elevated probability of mold growth and decreased feed quality. Molds have the potential to produce mycotoxins and other toxic funguses, and their presence in feed has the potential to decrease dry matter intake, alter rumen fermentation and suppress immunity in dairy cattle.

“Molds and mycotoxins can have considerable effects on dairy cattle health and performance, which can often go unnoticed for long periods of time,” says Jeff Kearnan, southwest region account manager, dairy enterprise sales, Arm & Hammer Animal Nutrition. “At the first sign of moldy grains, producers should work to compensate for the negative effects that molds can have on rumen health and herd performance.”

Mycotoxins can develop in almost any grain in the field or in storage, and can also be present even when mold is not visible. Slow drying seasons and mold can also lead to a drop in corn grain energy content by as much as 5 percent. For these and other reasons it’s important to test for feed quality and energy content on a regular basis and make ration adjustments to account for the differences.

Rumen fermentation can also be greatly altered by the inclusion of molds in the ration. Incorporating buffers and mold inhibitors can help reduce the impact of toxins on the digestive system. Buffers will improve rumen performance, maintain dry matter intake and stabilize acid production in the rumen. Rumen fermentation enhancers can also provide the rumen with the building blocks necessary for peak performance and keep the rumen working efficiently.

Ideally, it’s best not to include moldy feeds in any ration, but in circumstances such as this year’s harvest season, it may be unavoidable. If these feeds must be fed, introduce moldy feeds into the ration slowly, so cattle can adjust to the poor taste and dust. Feeding poorer quality feeds in tandem with higher quality ones can also help minimize the negative effects moldy feeds can have on cattle performance.

“By being proactive and developing a plan to neutralize the negative effects of moldy and toxic feeds, your herd will stay at peak performance,” says Kearnan. “Consult your nutritionist or veterinarian to help ensure your harvest is put to good use without incurring the potential negative effects of molds in your herd.”

Source: Arm & Hammer Animal Nutrition