Mycotoxins are toxic substances produced by naturally occurring metabolic processes in fungi. Mycotoxins can invade the seeds before the actual harvest whilst the crop is still on the field, or alternatively, mould growth can occur during storage at the feed mill or on the farm. As a result, high numbers of mycotoxins could already be present in the ingredients before they are received in feed mills or farms. Mould can also grow during feed processing especially when the temperature and humidity in the feed is increased during mixing. Finally, mould growth and mycotoxin production can also occur at the farm level from improperly cleaned silos, transport systems and feeders. The production of mycotoxins is enhanced by factors such as the moisture of the substrate (10 to 20%), the relative humidity (≥ 70%), the temperature (0 to 50°C, depending on the fungus species) and the availability of oxygen (Kanora and Maes, 2009). The most important role of feed mills is to keep the levels of mycotoxins as low as possible while multi-mycotoxin contamination should be also avoided. Most of the mycotoxins occur concurrently and a commodity usually contains more than one mycotoxin at the same time.
Test the raw ingredients
The best practical way to control mycotoxin levels is to use rapid test kit systems for the analysis of mycotoxins in raw ingredients which are not yet in silos. Different rapid test kit systems are validated for different mycotoxins and commodities and offer a very quick and effective way of raw material screening before they enter the feed mill. Once the levels are known, every feed mill can estimate the quality of its raw ingredients in terms of mycotoxin contamination and can effectively and more precisely (dosage adjustment) apply mycotoxin deactivator during feed production.
Test the finished feed
Another strategy of mycotoxin risk management is to test for the presence of mycotoxins in finished feeds. This method has some advantages and disadvantages. The most important advantage is that as every raw ingredient can bring its own mycotoxins into the finished feed and by only testing some raw ingredients by rapid test kits, some important raw ingredients whose inclusion is not high (5-10%) and which can still cause signifcant contamination of finished feed can be missed. Since the 1960’s, many analytical methods have been developed for the testing of mycotoxins in human food and animal feeds due to the concern of toxicity for human health. Among them, the methods of thinlayer- chromatography (TLC), enzymelinked immunosorbent assay (ELISA) and immunosensor-based methods have been widely used for rapid screening, while highperformance liquid chromatography (HPLC) with fluorescence detection (FD) and mass spectrometry detection (MS) have been used as confirmatory and reference. Accredited laboratory service is required for this step. The most important disadvantage is that analysis of finished feed takes quite a long time such that the tested feed is likely to have been fed to the animals by the time the results rom the analysis are known.
Use mould inhibitors
Storage mycotoxin contamination (ochratoxins, aflatoxins) can be prevented by keeping temperature and moisture content in silos low whilst grain is regularly aerated. In case perfect storage conditions cannot be guaranteed, use of mould inhibitor is highly recommended.
Apply mycotoxin deactivator
the final possible step in mycotoxin management is the application of a mycotoxin deactivator. These products work strictly in vivo and will not counteract or mask mycotoxin in stored feed or raw ingredients. It is highly recommended to apply effective mycotoxin deactivator which offers an opportunity to significantly improve animal health, performance, productivity and profit impaired by mycotoxins. Depending on the target performance different mycotoxins can be more or less problematic. Therefore, using different products for different animal groups become a rational trend.
These products work strictly in vivo and will not counteract or mask mycotoxin in stored feed or raw ingredients.
Kanora A. and Maes D. 2009. The role of mycotoxins in pig reproduction: a review.
Veterinarni Medicina, 54, 2009 (12): 565–576.
by Radka Borutova, Business Development Manager, Nutriad International
Published on Nutriad website on 01/03/2018