Mycotoxins are metabolites produced by toxigenic fungi which are of great concern as major food and feed contaminants. The ingestion of mycotoxins may damage the digestive mucosa and, once absorbed, may affect additional internal organs and the immune system, causing growth retardation and lower performance and making animals prone to suffer from infectious disorders.

Mycotoxin production is influenced by the type of substrates and environmental conditions, like moisture and temperature.  Mycotoxin contamination is an ubiquitous problem that can occur throughout the food chain, depending on the conditions of the field, harvesting, transportation, storage or processing.

Severity of mycotoxicosis depends on the fungi toxicity, the condition of the animal, including age and health and nutritional status, together with the synergistic effect of the combination of mycotoxins. Combination of two or more mycotoxins may potentiate the effect of one or all of them, increasing the severity of the signs.

MOST COMMON MYCOTOXINS IN ASIA DURING THE FIRST SEMESTER OF 2020

Research performed in Asia during the last decade showed that more than 90% of the samples of grain and feed tested were contaminated with at least one mycotoxin, and almost 70% were contaminated with two or more mycotoxins.

Most common isolated mycotoxin in the first term of 2020 is Fumonisin (FUM, 87%), followed by Deoxynivalenol (DON, 58%), Zearalenone (ZEN 53%) and Aflatoxin (AF 49%). In East Asia, the most prevalent mycotoxins were FUM, DON and ZEN, while in South Asia were FUM, AF and OTA and in Southeast Asia were FUM, DON, AF and ZEN. These mycotoxins are defined as the most prevalent in the area when they are present in more than 50% of the analysed samples.

Although the national authorities of the Asian countries have stablished different maximum levels of mycotoxins in feed, the presence of such toxins still negatively affects the economy in the livestock production. China and India are the areas of highest risk in the region, where the percentage of samples over the threshold is over 85%. Such risk in Southeast Asia is near 73%.

ECONOMIC IMPACT OF MYCOTOXIN CONTAMINATION

Economic losses caused by mycotoxin contamination of feed are linked to the reduction in the crop and feed value, the negative effect in the productivity of animals and the diseases caused by mycotoxins in animals and also in humans. Additionally, there are costs related to the management, prevention, and research of this topic.

In the case of Asia, it was estimated that the annual loss due to aflatoxins in Philippines, Indonesia and Thailand were about $900 million dollars, where $500 million of the costs were linked to the effects in human health.

MYCOTOXIN PREVENTION METHODS

Asia is constantly increasing the demand for livestock products, which has promoted the improvement of the efficiency of the productive systems. The increase in the livestock production has also increased the demand for animal feed in the continent.

Climatic conditions and crop management in Asia favour the high prevalence of mycotoxins, which represents an important threat for the livestock industry.  As mycotoxin contamination is a ubiquitous and serious problem, the demand of methods to prevent mycotoxicosis effects in the livestock in the region keeps increasing every year to improve the efficiency of the production cycle.

When the mycotoxin contamination is done at the preharvest stage, it is difficult to stablish preventive management measures, as it is highly dependent on the weather conditions. Therefore, farmers and feedmillers should apply adequate preventive measures in raw materials and compound feed during storage.

A combined approach of different feed additives should be done to protect the animals from the adverse effects of mycotoxins, based on:

1. The control of the growth of fungi in feed, to avoid the production of mycotoxins after the harvest.
2. The control of mycotoxins that can be already present in the grain before the harvest.

CONTROL OF FUNGAL GROWTH

The control of the growth of fungi can be done by using feed preservative additives. The use of active molecules from plant extracts, like cimenol ring, with recognised fungicidal activity, is the best choice for such purpose.

Cimenol ring has high affinity for microbial membranes. It is able to destabilize the membrane and cause the cell death by osmotic shock. Citric acid, a permeabilizing agent, creates pores in the membrane and enhances the entrance of cimenol ring inside the cell, increasing the antimicrobial activity of cimenol ring.

The use of cimenol ring as a natural preservative has several advantages against other products traditionally used for this purpose. The combination of cimenol ring with citric acid offers a wide spectrum activity against fungi, while its effectivity is demonstrated to last up to 6 months, ensuring a proper protection during all the storage of raw materials and compound feed.

The effectivity and superiority of the product is clearly seen in the graph below, comparing the UFC reduction in broiler feed between cimenol ring + citric acid (0.5kg/ton) and organic acids (2 kg/t). Compared to control, organic acids reduce the CFU by 32%, while the reduction is of 100% with cimenol ring.

Instead of other feed preservatives, the synergy of cimenol ring and citric acid is a safe formulation for the animals and the workers that manipulate the product, avoiding the irritation and other side-effects that other substances may cause.

CONTROL OF MYCOTOXINS

The control of mycotoxins is based on the use of mycotoxin binders, to avoid the negative effects of these toxins in the digestive tract (enteritis) and the absorption of the mycotoxins.

There are several molecules intended to bind mycotoxins and several factors should be considered in the election of a proper mycotoxin binder. First one, as in feed preservatives, is the spectrum of action, second one is the side-effect they may cause, because of secondary metabolites that can be produced or because the loss they cause on the nutritional value of feed, and lastly, the research and evaluation performed with the molecule.

Silicoglycidol is the only molecule that complies with the considerations mentioned above. It is a patented molecule obtained through an ionic and thermal treatment. Treatments applied into the molecule allows the creation of strong hydrogen bonds between Silicoglycidol and mycotoxins and ensures the capture of the different chemical groups of mycotoxins. Silicoglycidol has a great specificity against mycotoxins and, therefore, it does not interact nor affect the nutrients of the diet, like amino acids or vitamins, while there are no partial reactions that may produce toxic metabolites.

The deep research and investigation performed to design Silicoglycidol ensures its effectivity at low dosage, which is demonstrated through in vitro evaluations, using artificial digestive systems, and in vivo evaluations, where productivity and internal organs are assessed.

CONCLUSIONS

The livestock production in Asia is the fastest growing one and mycotoxins are a recognised risk, especially in the region, accounting for a considerable economic loss in the industry. Therefore, the need of an effective strategy to control mycotoxins present in feed is a key topic in the continent.

The knowledge of the available tools and their features are basic to choose the best solution available for the prevention of the negative effects caused by mycotoxins.

The use of natural feed preservatives based on cimenol ring is a safe and effective solution for feed preservation against other chemical products with limitations in spectrum and effectivity.

Silicoglycidol is the molecule of choice to prevent the negative effects of mycotoxins, as it is proved that the use of this solution at 0.5 kg/t in 1 million broilers is able to increase the meat production by 10 tons while reducing the feed utilisation by 18 tons.

The combination of the cimenol ring and the citric acid is marketed under the name of Alquermold Natural.

Silicoglycidol is marketed under the name of Alquerfeed Antitox.

BIBLIOGRAPHY:

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