Minimizing the effect of mycotoxin-contaminated silage on dairy cattle can sometimes feel like playing a game of whack-a-mole. When the negative impact of mycotoxins are observed on dairy cattle performance, applying a feed additive in the total mixed ration could be a solution.
Mycotoxins found in silage include, but are not limited to, deoxynivalenol (DON), zearalenone (ZON), mycophenolic acid, and roquefortine C. Fusarium species have the potential to produce DON and ZON while Penicillium the potential to produce mycophenolic acid and roquefortine C. When ingested by dairy cattle, mycotoxins are associated with appetite suppression, poor rumen function, ketosis, poor reproductive performance, and immune suppression.
A trial conducted in 2023 evaluated the potential of applying Crop-N-Rich® Nexus to limit mycotoxin impact in corn silage. Crop-N-Rich Nexus silage inoculant has been shown to improve fermentation, inhibit yeast and mold growth and limit nutrient losses during air exposure.
When used according to label instructions, Crop-N-Rich Nexus applies 100,000 colony-forming units (CFU) of Lactobacillus plantarum MTD/1® and 200,000 CFU of Lactobacillus buchneri PJB/1 per gram of forage. The MTD/1 bacteria in Crop-N-Rich Nexus produce lactic acid that quickly reduces the silage pH while the PJB/1 bacteria produce acetic acid, which inhibits yeast and mold growth, improving feedout stability.
Scientists took advantage of damp growing conditions that potentially favor mycotoxins, harvesting 22% dry matter corn silage and assigning it to one of two treatments: untreated or inoculated with Crop-N-Rich Nexus at the recommended rate of 1.5 grams per ton. Both treatments were packed in bucket silos and stored for 46 or 95 days. Buckets after 95 days were subsequently subjected to 12.8 days of air exposure before mycotoxin analysis.
In the untreated corn silage, levels of mycophenolic acid and roquefortine C increased from zero at ensiling to more than 5,000 and 8,000 parts per billion (ppb) respectively. In the corn silage treated with Crop-N-Rich Nexus, mycophenolic acid and roquefortine C were remained at levels lower than 98% in untreated corn silage. This finding highlights the benefit of treating corn silage with Crop-N-Rich Nexus on mycotoxins produced by Penicillium mold. However, it is important to note in this study, Crop-N-Rich Nexus had no significant effect on DON or ZON concentrations. Therefore, the inclusion of feed additives as a mycotoxin mitigation strategy should still be the primary approach for feeds high in mycotoxins. Practically speaking, in most on farm mycotoxin contamination cases a mixture of mycotoxins is present in the silage, so a multifaceted approach to minimizing effects and reducing mycotoxin risk is most likely warranted.
Crop-N-Rich Nexus can be a valuable tool as producers seek to harvest, store and feed high-quality forages. Crop-N-Rich Nexus preserves valuable nutrients in the silage, reduces the growth of yeasts and molds, limits silage heating, and decreases the concentration of detrimental mycotoxins produced by Penicillium molds when compared to untreated silage.
