Deoxynivalenol (DON) and zearalenone: two mycotoxins of importance in pig production

DON and zearalenone are two of the most frightening mycotoxins for pig producers because of two main reasons: they are very toxic in this species and highly prevalent, particularly DON.

The presence of these toxins in pig feed causes huge economic losses in North America and their prevalence remains high (and even increases) each year.

The toxic effects these mycotoxins have on pigs are responsible for their economic impact, which makes the use of prevention tools economically profitable. Mycotoxin binders are the most used solution, among which the patented molecule called Silicoglycidol stands out thanks to the broad spectrum of action and low effective dose.

Toxicity of DON and zearalenone in pigs

DON, also known as vomitoxin, belongs to the trichothecenes group. Its necrotizing activity is caused by the sesquiterpene group in its chemical structure (Borrell, 1990) and produces enteritis, which negatively affects digestion and nutrient absorption (Pierron, Alassane-Kpembi, & Oswald, 2016). Once absorbed, it can damage the internal organs, such as the liver, and decrease the organism’s detoxifying capacity; or cause immunodeficiency (Awad, Ghareeb, Böhm, & Zentek, 2013; Pierron, Alassane-Kpembi, & Oswald, 2016).

Pigs are particularly sensitive to this mycotoxin because they absorb it at high rates in the digestive tract and hardly biotransform it to the non-toxic metabolite DOM-1. Therefore, DON has important consequences in this species, even at low levels.

Zearalenone is mycotoxin of the lactonic group and has estrogenic activity (Borrell, 1990): affected pigs seem to be in heat. It mainly affects reproductive parameters, causing infertility and abortions. Vulvitis, particularly in gilts, and an increased uterus size are frequently observed in the affected animals (image 1) (Pierron et al., 2016).

Prevalence of DON and zearalenone in North America

Results of mycotoxin analysis in grain and byproducts used in animal diets show that DON and zearalenone have been constantly present in North America during the last years, and that DON contamination has been increasing, reaching the highest levels in 2020.

• A high percentage of the analyzed samples were contaminated with DON, which means that it is a highly prevalent mycotoxin in feed. DON is, in fact, one of the most prevalent mycotoxins: nearly 100% of the samples analyzed in the USA in 2020 were positive. For this reason, implementing effective prevention tools against DON is essential.
• Zearalenone contamination levels remained stable during the last years and significantly increased in 2020, probably due to the conditions in the harvests. This mycotoxin should be considered when designing prevention strategies, since it is usually present in mixed contaminations in the grain and can act synergistically with DON, boosting its toxicity.
• DON concentration in several samples in 2020 was above FDA recommended levels (5 ppm in feed ingredients and 1 ppm in the total ration) (Cvm, 2016; FDA, 2010).

Silcoglycidol as a prevention tool

Mycotoxins are highly resistant to chemical and temperature treatments (Borrell, 1990), and it is almost impossible to prevent their presence in grain, which leave mycotoxin binders as the most useful strategy to prevent their toxic effects.

Despite the broad variety of mycotoxin binders in the market, only a few of them meet the minimum requirements for an effective protection. Those are the solutions based on Silicoglycidol.

This patented molecule was developed by Biovet R&D department and is a unique solution in the market. During the patented production process of high temperatures and ionic exchanged, its structure is modified to be optimal for mycotoxin-binding, as it has:

• Broad spectrum of action. Effective against the different chemical groups common in the chemical structures of mycotoxins.
• Highly effective at low doses. Optimized structure that binds a high amount of mycotoxin per gram of binder, so that the effective dose rate is 0.5 kg/t.
• Effective throughout all the digestive tract. Hydrogen bonds that resist all the conditions in the digestive tract are created between the binder and mycotoxins, which remain attached to Slicoglycidol during all the digestive tract until excreted with feces to avoid irritation of the gut mucosa and mycotoxin absorption.
• High specificity. Silicoglycidol does affect the bioavailability of diet components, such as nutrients or drugs.

Silicoglycidol’s efficacy at the end of the digestive tract against DON and zearalenone is above 84.5% and 74.2%, respectively. These adsorption rates were evaluated in many trials following the scientific method, both in vitro (using a simulator of the digestive system) and experimental and commercial farms.

Results obtained in a trial conducted at a US university with pigs fed DON-contaminated diets show that Silicoglycidol can prevent the toxic effects of this mycotoxins and, consequently, improve feed conversion by 10%, despite the diet for the treated group had a higher amount of vomitoxin (2.6 ppm) than the control (2.4 ppm).

Conclusions

Mycotoxins represent a strong challenge in pigs that many times do not let them reach good performance standards. DON and zearalenone are among the most important mycotoxins in pigs because they are extremely sensitive to the toxic effects and these toxins are highly prevalent in feed: their prevalence in North America has been constant in the last years and increased markedly in 2020.

Silicoglycidol is an effective tool to completely protect of pigs against mycotoxins. It is effective to prevent their toxic effects (minimum adsorption rates for DON and zearalenone for Silicoglycidol are 84.5% and 74.2% at the end of the digestive tract). Besides, it was the first patented mycotoxin binder in the world (1988) and has many other advantages: it is effective at a low dose and against the main mycotoxin groups, and remains stable in all the conditions of the gastrointestinal tract.

Silicoglycidol can be found in the products of Biovet S.A.’s Mycotoxin Binders Line, such as Alquerfeed Antitox (100% composed of Silicoglycidol). This molecule was the first world patented mycotoxin binder (1998). Gel presentation was also patented in 2012.

 

Bibliography

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