Biosecurity and mycotoxin management in an ever-changing environment
Biosecurity aims to reduce biological risks, which cause disease and impair animal production; by limiting the introduction and circulation of contaminants on farms. Mycotoxins can impair animal health by challenging: the immune response, fertility, liver and kidney health or gastrointestinal tract integrity. Therefore, the potential for mycotoxin contamination should be included in biosecurity protocols. Symptoms of toxicity depend of multiple factors including the type of mycotoxins, of which there are currently more than 400. Those of most concern can be divided into six categories: aflatoxins, trichothecenes, fumonisins, zearalenone, ochratoxins and ergot alkaloids.
Mycotoxins can invade seeds before harvest, whilst crops are still in the field. Mould growth can also occur during storage on farm or at the feed mill. Mycotoxin development is influenced by many factors including; preceding crop, crop residues and plant variety. As well as weather during flowering and harvest - factors that change every year. This means that mycotoxin risk is an ever-present and ever-changing problem. Having a mycotoxin biosecurity control plan can help to practically manage mycotoxin risk, in this ever-changing environment.
Biosecurity measure No. 1: Predict the mycotoxin risk
It is essential for feed mills to keep the levels of mycotoxins as low as possible, whilst preventing multi-mycotoxin contamination. As mycotoxins commonly co-exist, resulting in any one raw material containing numerous mycotoxins at the same time. The best and most practical way to test and control mycotoxin levels is to use rapid test kit systems on raw materials before they are stored in silos. In this way they offer a very quick and effective way of screening raw materials before they enter the feed mill. A number of tests have been carried out using different rapid test kit systems, in order to validate them for different mycotoxins and raw materials. Once the levels of mycotoxins are known, each feed mill can then estimate the quality of its raw ingredients in terms of mycotoxin contamination. This means that a mycotoxin deactivator can be more effectively and more precisely (dosage adjusted) applied during the production of feed.
Biosecurity measure No. 2: Prevent the increase of mycotoxin levels during storage
The quality of raw materials and feed is determined by its composition and its microbiological load. The number of mould spores is a particularly important factor. In the field, before harvest, little can be done about mould contamination and subsequent toxin production. However, post-harvest there are several strategies that can be adopted to help control the growth and development of moulds; in order to reduce their effects on raw material quality, feed quality and animal performance. Correct storage of raw materials and feed can alleviate many issues; having clean and well-ventilated silos is particularly important. Mould inhibitors can also be used to control moulds and hence mycotoxin contamination.
A practical and widely used method to control mould growth in stored raw materials and feed is through the Feed and Feed Materials Treatment Programme from Adisseo. This programme includes Mold-Nil®, a product that has been developed and approved for use, to assist in the safe storage and management of raw materials used in animal feeds. The product contributes to the production of a safe food supply for consumers.
Mold-Nil®, available in both liquid and dry form, is uniquely formulated with a synergistic buffered blend of propionic and other organic acids, for effective mould inhibition. The use of Mold-Nil® is well-established in preventing mould contamination in raw materials and feed, thereby stabilising the nutritive value; as well as allowing safe-handling throughout long-term storage.
Biosecurity measure No. 3: Screen mycotoxins in the finished feed
Another mycotoxin risk management strategy is to test for the presence of mycotoxins in finished feeds. This method has both advantages and disadvantages. The key advantage is that by testing the final mixture, mycotoxins present in all the individual raw ingredients are more likely to be identified. Whereas, when using rapid test kits some important, but low inclusion (5-10%), raw materials can be missed. These missed mycotoxins can still cause significant contamination of finished feed.
Since the 1960’s, many analytical methods have been developed to test for mycotoxins in human food and animal feeds, due to the concern over their toxicity and effects on human health. Among them, the methods of thin-layer-chromatography (TLC), enzyme-linked immunosorbent assay (ELISA) and immunosensor-based methods have been widely used for rapid screening. Whilst, high-performance liquid chromatography (HPLC) with fluorescence detection (FD) and mass spectrometry detection (MS), have been used as confirmatory and reference tests. An accredited laboratory service is required for these methods. The key disadvantage of analysing finished feed is that by the time the results from these lengthier techniques are known, the feed will have been consumed already.
Biosecurity measure No. 4: Apply an effective mycotoxin deactivator
The final stage in mycotoxin management is the application of a mycotoxin deactivator. These products work only within the animal (in vivo) and will not counteract or mask mycotoxins in stored raw materials or finished feed. Some of these products deactivate the toxins directly in the gastrointestinal tract of animals; based either on adsorption of those mycotoxins with suitably located polar functional groups, or by biological degradation (bio-inactivation) or they act to counteract the secondary negative effects of mycotoxins. Unike® and Toxy-Nil®, products lines from Adisseo, are specially developed feed additives that protect animals from mycotoxicosis by adsorption and bio-inactivation; along with organ, immune and antioxidant system support. As such they represent an optimal and highly recommended solution for mycotoxin management in farm animals. Utilising an effective mycotoxin deactivator offers an opportunity to significantly improve animal health, performance, productivity and profit; all of which can be impaired by mycotoxins. Depending on performance targets, certain mycotoxins will have different effects on the productivity. Therefore, using specific products and dosages for different animal groups is necessary.
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