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Environmental Challenges in Feed John Doerr, PH.D., PAS, DPL, ACAP Agrarian® Solutions
Guide for Mycotoxins in Dairy
F
rom planting to harvest the scuttlebutt we’ve gotten on mycotoxin issues this year has been, “… not seeing too much this summer,” “… better than last by far,” and “… not getting so many positive toxin reports this season.” Well, we’ve reached the end of the 2021 crop season and the data are now in. Let’s see if these reports were accurate. • You can’t predict mycotoxins in feedstuffs by eye! Much of the 2021 corn and soy crops look really good. But, mycotoxins, and sometimes even the molds that produce them, are found in abundance hidden from our view. Don’t rely on visual cues to determine if mycotoxins are a risk this year. Good testing is the only way to know for sure. • Averages for Michigan, Indiana and Wisconsin. For the period (May-Sep) average values for all samples submitted were ~130 ppb for zearalenone (moderate risk), ~760 ppb DON (moderate risk), ~140 ppb T-2 toxin (moderate-high risk), and ~300 ppb fumonisins (very low risk). • High values matter. Considering the two points above, average DON was lower (May-September) this year than last. Keep in mind the reported averages are for all submitted samples, not just DON positives. But the high value for DON was dramatically higher for 2021 silage than for 2020 in the same period. While it is always nice to see some negative reports, a sample showing nearly 16,000 ppb DON means many cows in that herd were under severe DON challenge. • Mycophenolic Acid – a Problem? Mycophenolic acid appeared all too frequently. August shows 60% of all samples submitted were positive for this toxin. Generally, Mycophenolic will be accompanied by another mycotoxin, roquefortine C; however, that toxin is not being tested at this time.
Approximate range for potential reaction Mycotoxin
Low
Medium
High
DON (vomitoxin)
<300 ppb
300-1,000 ppb
>1,000 ppb
Zearalenone
<100 ppb
100-300 ppb
>300 ppb
Aflatoxin
<10 ppb
10-30 ppb
>30 ppb
T-2 toxin
<75 ppb
75-150 ppb
>150 ppb
Fumonisin
<600 ppb
600-1,500 ppb
>1,500 ppb
• When is mycophenolic acid a risk? Observations of mycophenolic acid over the past two years suggest that dairy cattle risk is likely significant at levels of 1,000-1,500 ppb. • What feedstocks harbor mycophenolic acid? Mycophenolic acid is usually found in silage, particularly corn silage. This year, that toxin has shown up (in fairly high amounts) in TMR, HMC, shell corn, and even first cutting hay. And those samples came from Iowa, Michigan, Wisconsin, and Pennsylvania, showing a broad geographic range. Actlabs, a global leader in analytical lab services, provides these independent and state of the art results. In each sample, 17 mycotoxins are analyzed and reports provided to producers include estimates of the degree of severity of the concentration(s) found. Complimentary testing is available through your CentralStar team so you know for sure which environmental challenges your dairy may be facing. Mycotoxins can impact herd profitability by reducing milk production, reproduction success and overall herd health. Dairy producers and nutritionists across the U.S. rely on Select DTX and Select BioCycle Plus to resolve the negative impacts of mycotoxins. Talk to your CentralStar team to learn more.
TOXIN CONSEQUENCES DON (vomitoxin)
Zearalenone
Aflatoxin
T-2 toxin
Fumonisin
Reduced feed intake / feed refusal
Hyper-estrogenism
Liver damage; altered protein synthesis
Reduced feed intake
Reduced feed intake
Intestinal hemorrhages
Reduced milk production
Frequent defecation
GI tract ulceration
Bloody diarrhea
Impaired immune function
Reduced milk production; reduced milk fat Poor reproductive performances Elevated SCC Impaired immune function Loose, inconsistent manure
Poor reproductive performance including: • Short cycle heats • Cystic cows • Multiple ovulations • Vaginitis • Enlarged mammary glands in virgin heifers
Decreased appetite/off feed Lower milk protein Impaired immune function Increased disease rates Highly interactive Rough hair coat
Sample Submission Form
Absence of estrous Impaired immune function Increased disease rates
CentralStar Cooperative
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