In this article we recap on unregulated fungal metabolites that should be on the livestock industry’s radar.
In an earlier blog post, we looked at the toxicity and occurrence of emerging and masked mycotoxins in feed materials and showed that they commonly occur in feedstuffs. In September 2016, a new scientific paper (Gruber-Dorninger et al) from the Biomin Research Center, in cooperation with of IFA Tulln, summarised the current understanding regarding less well-understood mycotoxins that are not currently subject to regulation, and whether there’s cause for concern in food-producing animals. Based on the scientific review, here are the emerging culprits that merit greater scrutiny going forward:
Moniliformin (MON) shows severe effects in vivo that are of big concern for poultry. This mycotoxin can cause symptoms like heart damages, muscular weakness, respiratory distress, decreased feed intake and impaired immune function. Moreover, moniliformin showed toxicity towards different cell lines in vitro. Due to its high prevalence in cereals, the European Commission requested a scientific opinion from EFSA concerning the risk for public health related to MON. This opinion is expected soon.
Due to its structural affinity to aflatoxin, sterigmatocystin (STE) is of particular concern for ruminants. Dietary exposure to 12 ppm of feed showed negative effects in ruminants, including bloody diarrhea, reduced milk production and mortality in some cases. Toxicity was observed in one swine trial as well. Studies were also carried out on chicken embryos. Thanks to this new data available the Joint FAO/WHO Expert Committee on Food Additives (JECFA) is currently working on a safety assessment of sterigmatocystin.
Previously, we reported the toxic effects of enniatins (ENNs) on mitochondria in vitro. A few studies were also conducted in vivo on rats and chickens. Traces of dietary enniatins were found in eggs, meat, skin and liver of broilers. EFSA concluded that acute exposure is not an issue for humans, but no conclusions could be drawn for chronic exposure due to a lack of data.
Beauvericin (BEA) possess lipophilic proprieties and may have negative effects on humans, since it may inhibit several cellular transporters that are also involved in increasing bioavailability of certain pharmaceuticals. For example, beauvericin could promote breast cancer in humans through inhibition of specific proteins)
In a survey conducted on poultry products, traces of BEA were found in eggs, meat and liver samples. It was suggested that due to its lipophilic proprieties BEA could accumulate in the yolk. Similarly to enniatins, EFSA concluded that acute exposure should not be of concern for humans, though no conclusions could be drawn for chronic exposure.
Fusaproliferin (FP) is a frequently occurring mycotoxin that has been shown to have teratogenic and pathogenic effects through in vivo toxicity studies on chicken embryos and brine shrimp larvae.
Oral administration of fusaric acid (FA) to pigs at a concentration of 200 mg/Kg BW affected the nervous system and caused vomiting. Fusaric acid FA is produced by Fusarium species, and may have synergistic effects with other trichothecenes. In one study, pigs fed fusaric acid and deoxynivalenol (DON) had decreased weight gain and lower feed intake.
Alternariol (AOH) showed mutagenic proprieties on several mammalian cell lines. AOH showed synergism with zearalenone (ZEN) and was able to inhibit progesterone secretion in cultured porcine cells. These findings suggest that alternariol could have negative effects on reproductive parameters in pigs and other mammalian species. In 2011 EFSA concluded that AOH could be potentially harmful to humans and pointed out the need of further investigations to generate toxicity data.
Tenuazonic acid (TeA) is thought to interfere with protein synthesis and its effects were studied in vivo on several animal lines including chickens. Dietary exposure of broilers to 10 ppm TeA for 3 weeks caused macro- and microscopic lesions in various organs, leading to decreased weight gain and lower feed efficiency. EFSA concluded that on the basis of current toxicity data, adverse effects cannot be fully ruled out for chickens.
Forefront of research
Our understanding of emerging and masked mycotoxins is advancing thanks to the progress in analytical chemistry and the increasing interest from producers and regulatory authorities. The road is still long and more data will have to be generated to fully elucidate the role of these compounds in animal and human nutrition. BIOMIN is committed to research and works in tight cooperation with world-leading research organisations such as IFA Tulln in Austria, a hotbed of mycotoxin research. Our robust R&D programme helps us to provide the animal protein industry with continuous innovations in the field of mycotoxin risk management, such as the LC-MS/MS based Spectrum 380® programme that can detect masked and emerging mycotoxins in raw commodities and finished feed.