Mycotoxin treatment: mission possible?

Author: Dr. Radka Borutova, DVM, Ph.D., Alltech Mycotoxin Management

What are mycotoxins?

Mycotoxins are toxic compounds that are produced by certain types of molds or fungi. Although officially discovered almost 60 years ago, the agricultural sector still has a lot to learn about their development, impacts and methods to reduce the threat to both humans and livestock. Mold growth on grains, forages and feedstuffs, either pre- or post-harvest, is something most people will have observed. However, the reason why these molds produce mycotoxins remains uncertain. Mycotoxins, which are invisible to the naked eye, are often found at increased levels during periods of extreme weather, either warm or dry, and in damp, humid conditions, indicating that molds may produce these toxins in response to stress or as a defense mechanism.

Several hundred different mycotoxins have been identified, but the most commonly observed mycotoxins concerning human health and livestock include:

• Aflatoxins
• Ochratoxin A
• Fumonisins
• Zearalenone
• Deoxynivalenol
• Ergot alkaloids

Mycotoxin prevention or treatment?

Test ingredients prior to feed production

Although there are many practical steps producers can take pre-harvest to try to reduce the mycotoxin contamination risk in grains and forages, the results of mycotoxin analysis continue to show the inevitable presence of these unwanted toxins in the feed supply chain. Rapid test kits, such as the Neogen Raptor® that is linked to Alltech® RAPIREAD™, provide a quick, practical and validated method of identifying the mycotoxin risk in raw ingredients prior to storage. With this knowledge, feed producers can take the appropriate steps to safeguard feed quality. Where necessary, they can accurately apply technologies like adsorbents that help mitigate the mycotoxin challenge when the feed is delivered to livestock. Most rapid test devices can detect a maximum of 6–8 main mycotoxins compared to laboratory testing.

Test finished feeds before feeding to animals

Testing finished feeds has the advantage of detecting the overall mycotoxin challenge in an animal’s diet. If all raw ingredients are not individually tested, some mycotoxins may go undetected, particularly ingredients with a low inclusion rate (5–10%) but can still cause significant contamination risk.

To detect mycotoxins in finished feeds, samples are normally sent to accredited laboratories that use methods such as thin-layer chromatography (TLC), enzyme-linked immunosorbent assay (ELISA), immunosensor-based methods, high performance liquid chromatography (HPLC)  or ultra performance liquid chromatography with mass spectrometry detection (UPLC-MS). The Alltech 37+® mycotoxin analysis employs UPLC-MS to search for up to 54 mycotoxins in each animal feed sample. With laboratory methods having a longer sample turnaround time than rapid tests, many producers will use rapid testing combined with laboratory testing as part of an overall mycotoxin control plan.

Storing raw materials and finished feeds

Mold proliferates in damp and humid conditions, creating opportunities for the development of storage mycotoxins such as ochratoxins and aflatoxins. Clean silos, careful drying of incoming grain, effective aeration and routine monitoring of grain quality can all help to reduce the opportunities for fungal growth. Where storage conditions and potential mold growth is a concern, mold inhibitors such as Mold-Zap® can be applied to stored grain to reduce the fungal burden.

When ensiling forages, the quicker and better it can be consolidated, the lower the oxygen concentration. Lowering oxygen in the clamp lessens the risk of yeast and mold growth, subsequently reducing the mycotoxin risk.

What if the animal consumes mycotoxins?

Even with best-practice pre-harvest and storage management and robust testing programs, there are often unavoidable scenarios where the final feed delivered to animals contains mycotoxins, leading to many potential negative impacts on health and performance. At this point, the inclusion of mycotoxin adsorbents such as Mycosorb A⁺® can be utilized to adsorb the toxins directly in the animal’s gastrointestinal tract, removing them before they have a chance to cause harm to the animal. Alltech’s Mycosorb A⁺ combines both modified yeast cell wall extract (YCWE) and algae to allow for the adsorption of a broader range of mycotoxins than YCWE would be capable of on its own. These types of products work strictly in vivo and will not counteract or mask mycotoxins in stored feed or raw ingredients.

A holistic approach to mycotoxin management

As highlighted here, effective mycotoxin management is about seeing the whole challenge, from the farm to the feed mill and from risk assessment to feed management. To effectively manage the inevitability of mycotoxin contamination, producers should understand the level of mycotoxin challenges in their business to ensure the right steps can be taken to mitigate any adverse effects on animal performance, production efficiency and food safety.