The mycotoxin assay summaries presented in Table 1 and 2 and Figures 1 and 2 for the 517 corn silage and 558 TMR samples collected between October 1, 2025 and April 30, 2026 indicate a high number of samples contaminated by two to four mycotoxins. The frequency of multiple mycotoxin-contaminated samples and the compounding effects supports  the regular sampling of feed ingredients and diets, as well as the adaption of time-proven and research-verified mycotoxin mitigation protection. 

Corn silage samples continue exhibiting the familiar pattern of high-risk DON contamination and medium-risk zearalenone (ZEA) levels observed in recent years. However, elevated fumonisin (FUM) levels are being detected. Samples from Maryland, North Carolina, Pennsylvania, and Virginia exhibited high-risk levels of FUM, while an additional five Midwestern states reported medium-risk FUM contamination. 

The TMR contamination levels of DON were in the high-risk category for eight states and 11 states were at a high- or medium-risk level of ZEA. As expected from the corn silage FUM results, 14 states assayed low- and medium-risk levels of FUM in the TMR. More importantly than evaluating individual mycotoxin levels is to note that 11 states submitted TMR samples testing at medium- or high-risk levels for two or three mycotoxins, and Pennsylvania and Virginia assayed medium- or high-risk contamination levels for four mycotoxins. 

The presence of multiple mycotoxins exacerbates the digestive, immune, and reproductive insults of the individual mycotoxins and necessitates a proven mycotoxin mitigation program. For example, DON disrupts digestive function, ZEA reduces reproductive success by imitating estrogen, FUM accelerates leaky gut and reduces liver function, and finally T-2 earns the “assassin” nickname by killing high-turnover gut and immune cells.

The production response observed in high-producing dairy cows supplemented with DTX™ in Roth et al. (2024^a,b) occurred when diets tested at high-risk DON levels and medium-risk ZEA levels. Dairy nutritionists and producers are observing very good milk production and reproductive success outcomes when feeding DTX consuming diets with multiple mycotoxins at medium- and high-risk levels. Contact your Agrarian Solutions representative for advice on developing a mycotoxin testing program and utilizing DTX in your clients’ herds.

^aRoth, L.D., et al. 2024. J. Dairy Sci. 107(Suppl 1):426. (Abstr.)
^bRoth, L.D., et al. 2024. J. Dairy Sci. 107(Suppl 1):426. (Abstr.)

The post Mycotoxin Report: October 1, 2025 – April 30, 2026 appeared first on Agrarian Solutions.

The lingering effects of a challenging 2024 growing season were evident in the mycotoxin summaries across the US for corn silage and TMR samples from April 30, 2025 through September 30, 2025. While DON and zearalenone continue to be the primary mycotoxins in both sample types, Fumonisin is evident in the mid-Atlantic region. The mycotoxin summaries are presented in Table 1 and 2 and Figures 1 and 2 for the 248 corn silage and 354 TMR samples, respectively. 

For the past several years, DON and zearalenone contamination have been consistently high for the northeast third of the US for corn silage, and now KS and WI are testing high for DON. North Carolina, Virginia, and Pennsylvania have similar DON concentrations as the last survey, medium to high risk, but fumonisin has increased significantly in corn silage and TMR to the high risk level. 

As important as mycotoxin testing is for identifying potential challenges, the confirmation of cow performance and health is the definitive answer on the need for mycotoxin protection. The herd indicators of milk components, manure consistency, health events, and reproduction will indicate how well the cows are handling the mycotoxin load in the feed in addition to other challenge factors they are encountering. Using both the sample results and herd indicators will drive the decision determining the amount of DTX to feed. It is important to note that independent meta-analyses of Kihal et al (2022)¹ suggest that the traditional feed ingredients thought to provide mycotoxin protection are more deleterious at reducing the bioavailability of key nutrients.

Agrarian Solutions provides complimentary mycotoxin testing in feed ingredients and TMR to aid dairy producers and nutritionists in determining the correct amount of DTX is fed to support performance. Contact your Agrarian representative for assistance testing feeds and analyzing test results throughout the year. 

The post Mycotoxin Report: April – September 2025 appeared first on Agrarian Solutions.

Following a challenging 2024 growing season in much of the US, mycotoxin levels increased in corn silage and TMR samples from October 1, 2024 through March 31, 2025. The trend for elevated DON was present in both types of samples, and most notable was the elevated fumonisin content in corn silage and TMR samples from the mid-Atlantic and East. Sample data is presented in Table 1 and 2 and Figures 1 and 2 for the 323 corn silage and 506 TMR samples, respectively. Throughout the Northeast, DON and zearalenone contamination have been consistently high in the last several surveys. DON is at a high-risk level from Pennsylvania to the north through New York paired with medium risk for zearalenone in corn silage and TMR samples.

North Carolina, Virginia and Pennsylvania have similar DON concentrations as the last survey, medium to high risk, but fumonisin has increased significantly in corn silage and TMR to high risk. Kentucky and Tennessee have also seen a significant increase in fumonisin concentration in corn silage and TMR. Both states have a medium risk for DON but are at high risk for fumonisin. In the Upper Midwest, TMR and corn silage concentrations of DON and zearalenone are shifting higher and fumonisin is becoming more prevalent in TMR samples. Singular mycotoxins are at medium risk levels for corn silage and TMR, but with several mycotoxins present in the corn silage and TMR samples the entire TMR has shifted into the high-risk category. More than what the assay results say, what the cows tell us is the most important deciding factor for deploying a mycotoxin mitigation program. Paying close attention to milk components, manure consistency, health events, and reproduction will give indicators to how the cows are handling the mycotoxin load in the feed in addition to other challenge factors they are encountering. Using both the sample results and herd indicators will drive the decision for the amount of DTX to feed. Additionally, as we look forward to corn silage harvest, it is important to assess freshly chopped corn silage for mycotoxins in preparation for successfully transitioning to the next forage crop.

Agrarian Solutions provides complimentary mycotoxin testing in feed ingredients and TMR to ensure the right amount of DTX is fed to support performance. Contact your Agrarian representative for assistance testing feeds and analyzing test results throughout the summer heat stress and fall harvest seasons.

The post Mycotoxin Report: October 2024 – March 2025 appeared first on Agrarian Solutions.

Larry Roth, Ph.D., PAS, Vice President of Nutrition

Regional differences were clear for mycotoxin assay results for the 505 corn silage and 303 TMR samples collected between March 1 and September 30, 2024, as displayed in Table 1 and 2 and Figures 1 and 2 for the TMR and corn silage respectively.

Following earlier trends, both corn silage and TMR assays suggest DON contamination is the greatest concern in the Northeast and Great Lakes regions with 14 states averaging high risk results for corn silage and 9 states posting TMR averages in the high-risk zone. Interestingly, WI state-wide averaged just over 1,700 ppb DON; however, individual values ranged from low in the western part of the state to very high in the eastern section of WI. A trend that merits watching is the high fumonisin levels in corn silage and TMR for NC, VA and PA as these areas experienced drought conditions during the 2024 growing season.
S
ix states had TMR DON readings in the high-risk category paired with zearalenone levels greater than 150 ppb. The drought conditions in VA likely resulted in the state’s TMR samples assaying in the high-risk range for DON, T-2 and fumonisin as well as medium risk for zearalenone.

The mycotoxin assay results and risk ranges for individual mycotoxins are only part of the decision of utilizing DTX™ as a herd management tool. The occurrence of multiple mycotoxins in the final diet compounds the challenges posed by each single toxin as the animal must defend and protect against the cumulative toxin load. Consequently, past field experiences of dairy nutritionists and producers indicate that herd indicators (health, reproduction and production), or “what the cows are telling us”, must be teamed with mycotoxin assay results to ultimately determine whether DTX should be fed for mycotoxin protection, as well as the amount of DTX. In situations involving the feeding of a high-risk mycotoxin-contaminated diet and multiple herd indicators, nutritionists and producers relate positive results from supplementing the BioCycle™ Plus product.

Agrarian Solutions encourages nutritionists and livestock producers to submit TMR and feed ingredients for mycotoxin evaluation to determine correct protection strategies. Please contact your regional Agrarian representative for assistance with sample submittal and result evaluation.

The post Mycotoxin Report: March – September 2024 appeared first on Agrarian Solutions.

Larry Roth, Ph.D., PAS, Vice President of Nutrition

Mycotoxin assays of TMR and corn silage samples indicate regional variations in mycotoxin contamination levels across the US. The summary of the 452 TMR samples and 232 corn silage samples collected between October 1, 2023, and February 29, 2024 are displayed in Tables 1 and 2 and Figures 1 and 2 for TMR and corn silage, respectively.

Consistent with the past several years, the TMR assays suggest DON contamination is the greatest concern in the northeastern third of the country with nine states averaging high risk results and another three states almost making that list. Although state-wide WI TMR samples averaged 980 ppb DON, a wide range existed between extreme contamination in eastern WI near Lake Michigan and clean TMR samples in western WI next to the Mississippi River.

Zearalenone (ZEA) contamination averaged medium risk in only six states; however, each of those states were also high risk for DON, which compounds the negative effects of each individual mycotoxin. Interestingly, fumonisin contamination has been trending up over the last several years and TMR assays from IL, OH and MI averaged in the medium risk level during the sampling period.

Corn silage assay results continue to implicate this important feed ingredient as the major mycotoxin source. As previously mentioned for TMR samples, WI showed a tremendous east-to-west variation in DON contamination of corn silage, and in fact was the second-highest state for corn silage DON levels. Although the GA corn silage sampling was limited in scope, with only 9 submittals, the assays results averaged in the high-risk level for DON, ZEA, fumonisin and in the medium risk category for T-2. University research evaluating fungicides, application timing and hybrid susceptibility to mycotoxin contamination of corn silage should be closely followed.

Agrarian Solutions encourages nutritionists and livestock producers to submit TMR and feed ingredients for mycotoxin evaluation to determine correct protection strategies. Please contact your regional Agrarian representative for assistance with sample submittal and result evaluation.

The post Mycotoxin Report: October 2023 – February 2024 appeared first on Agrarian Solutions.

Larry Roth, Ph.D., PAS, Vice President of Nutrition

Mycotoxin evaluation is a key component of the Agrarian Mycotoxin Protection Program. The mycotoxin summary results for April 1 through September 30, 2023 are displayed in figures 1 and 2. These values reflect a combination of preserved 2022 feeds and newly harvested 2023 corn silage. For corn silage and dairy TMR samples, respectively. Mycotoxin assay results vary considerably across the United States. The past trend is for mycotoxin levels to increase as we move from the Plains States east to PA and NY, and there is not a clear pattern of 2022 vs 2023 values.

The states of OH, NY and PA reported elevated DON, zearalenone and fumonisin levels for an unfortunate trifecta. The IL fumonisin TMR levels were surprisingly high given the moderate levels of the corn silage, which suggests the feeding of contaminated by-products.

I encourage you to participate in the Agrarian mycotoxin testing program. We are emphasizing recording crop for the corn silage samples to identify year to year changes, as well as variability through the year. In addition, please consider the value of monthly monitoring of TMR and corn silage for mycotoxin variation. Proactive sampling may help to identify challenges before escalating. Contact your Agrarian representative for the latest on mycotoxin evaluation.

The post Mycotoxin Report: April – September 2023 appeared first on Agrarian Solutions.

Larry Roth, Ph.D., PAS, Vice President of Nutrition

Mycotoxin summary results for October 1, 2022 through March 31, 2023 are displayed in figures 1 and 2 for TMR and corn silage samples, respectively. Generally, Eastern States, with higher rainfall patterns, posted higher mycotoxin levels than the Plains States experiencing drier conditions or drought.

Ohio’s TMR assay results were most problematic with a combination of elevated DON and zearalenone readings to affect both digestion/nutrient absorption and reproductive success. Interestingly, Ohio’s corn silage zearalenone levels were not that concerning, suggesting that by-products being fed could be significant zearalenone contributors to the Ohio TMR values. Conversely, Michigan TMR mycotoxin levels were somewhat lower than what might be predicted from the state’s corn silage assays.

High fumonisin corn silages values were observed along the Eastern Seaboard from South Carolina through North Carolina, Virginia and into Maryland and Pennsylvania. Fortunately, other feed ingredients must have been relatively low in fumonisin to create the safe levels seen in the TMR samples.

I encourage you to participate in the Agrarian mycotoxin testing program. We are emphasizing recording crop year for the corn silage samples to identify year to year changes, as well as variability through the year. In addition, please consider the value of monthly monitoring of TMR and corn silage for mycotoxin variation. Proactive sampling may help to identify challenges before escalating. Contact your Agrarian representative for the latest on mycotoxin evaluation.

The post Mycotoxin Report: October 2022-March 2023 appeared first on Agrarian Solutions.