In many cases, livestock producers won’t be aware of the presence of mycotoxins. There may be no visible mold and no bad smell, yet the infestation can be there, waiting to drag down production, decrease herd health, lower fertility and even be a food safety hazard, according to Lallemand Animal Nutrition.
“While mycotoxins are produced by specific molds, visible signs of mold may not translate to measurable mycotoxin levels, and vice versa,” said Dr. Renato Schmidt, technical services-silage, Lallemand Animal Nutrition. “It’s virtually impossible to completely avoid mycotoxin exposure. The toxins can be produced both on the growing crop and during storage and feedout.”
To help reduce mycotoxin production, producers can plant insect- and disease-resistant varieties, avoid leaving stubble standing in the field and practice crop rotation, Lallemand said. In addition, it helps to avoid or minimize the effects of plant stressors, like inadequate fertilization. Still, producers cannot avoid damage from pest infestation or weather events that can predispose crops to mold infestation and mycotoxin production.
When the crop has been stressed or physically damaged, the potential for mold infestation significantly increases. In these cases, Schmidt advised producers to take extra care with silage management.
To help minimize mycotoxin-producing molds — and all molds that cause spoilage — producers should use proven silage inoculants as part of a good overall management program.
In the ensiling structure, molds tend to grow in hot spots where air (oxygen) is present, Schmidt noted. This is typically in poorly sealed surface layers, corners or shoulders of ensiled forages or where pockets of air were trapped and packing was inadequate.
“If visibly moldy silage is identified, discard it,” Schmidt said. “Feeding even small amounts of spoiled silage into a ration has been shown to reduce dry matter intake and (neutral detergent fiber) digestibility of the whole ration. While it may feel like an economic hit, you’re risking more in terms of lost production, herd health and reproduction if you choose to feed spoiled silage.”