The atlas compiled by these editors is a commendable effort and welcome addition to the mycology textbook sector. Up until now, the publication of medical mycology textbooks has been sparse and those that have been published are either too detailed for a resident in training or practicing physician or do not provide sufficient photographs or illustrations of the main features of the mycotic organisms. As a lecturer in mycology for the dermatology residents at my local teaching hospital and program, there are 3 key objectives of my mycology lectures: (1) to provide some type of organizational approach to mycotic organisms, (2) to provide a concise clinical history, and (3) to provide as many photographs and illustrations of mycotic organisms as possible. This atlas provides an exemplary addition to my book collection on medical mycology textbooks and sources for illustrations of mycotic organisms. The electron photomicrographs, photoplates, and line drawings of

Atlas of Clinical Fungi

Mycotoxins are secondary metabolites produced by fungi especially those belonging to the genus Aspergillus, Penicillum and Fusarium. Mycotoxin contamination can occur in all agricultural commodities in the field and/or during storage, if conditions are favourable to fungal growth. Regarding animal feed, five mycotoxins (aflatoxins, deoxynivalenol, zearalenone, fumonisins and ochratoxin A) are covered by EU legislation (regulation or recommendation). Transgressions of these limits are rarely observed in official monitoring programs. However, low level contamination by Fusarium toxins is very common (e.g., deoxynivalenol (DON) is typically found in more than 50% of the samples) and co-contamination is frequently observed. Multi-mycotoxin studies reported 75%–100% of the samples to contain more than one mycotoxin which could impact animal health at already low doses. Co-occurrence of mycotoxins is likely to arise for at least three different reasons (i) most fungi are able to simultaneously produce a number of mycotoxins, (ii) commodities can be contaminated by several fungi, and (iii) completed feed is made from various commodities. In the present paper, we reviewed the data published since 2004 concerning the contamination of animal feed with single or combinations of mycotoxins and highlighted the occurrence of these co-contaminations.

Current Situation of Mycotoxin Contamination and Co-occurrence in Animal Feed—Focus on Europe

Some foods and feeds are often contaminated by numerous mycotoxins, but most studies have focused on the occurrence and toxicology of a single mycotoxin. Regulations throughout the world do not consider the combined effects of mycotoxins. However, several surveys have reported the natural co-occurrence of mycotoxins from all over the world. Most of the published data has concerned the major mycotoxins aflatoxins (AFs), ochratoxin A (OTA), zearalenone (ZEA), fumonisins (FUM) and trichothecenes (TCTs), especially deoxynivalenol (DON). Concerning cereals and derived cereal product samples, among the 127 mycotoxin combinations described in the literature, AFs+FUM, DON+ZEA, AFs+OTA, and FUM+ZEA are the most observed. However, only a few studies specified the number of co-occurring mycotoxins with the percentage of the co-contaminated samples, as well as the main combinations found. Studies of mycotoxin combination toxicity showed antagonist, additive or synergic effects depending on the tested species, cell model or mixture, and were not necessarily time- or dose-dependent. This review summarizes the findings on mycotoxins and their co-occurrence in various foods and feeds from all over the world as well as in vitro experimental data on their combined toxicity.

Natural Co-Occurrence of Mycotoxins in Foods and Feeds and Their in vitro Combined Toxicological Effects

Deoxynivalenol (DON) is a mycotoxin primarily produced by Fusarium fungi, occurring predominantly in cereal grains. Following the request of the European Commission, the CONTAM Panel assessed the risk to animal and human health related to DON, 3-acetyl-DON (3-Ac-DON), 15-acetyl-DON (15-Ac-DON) and DON-3-glucoside in food and feed. A total of 27,537, 13,892, 7,270 and 2,266 analytical data for DON, 3-Ac-DON, 15-Ac-DON and DON-3-glucoside, respectively, in food, feed and unprocessed grains collected from 2007 to 2014 were used. For human exposure, grains and grain-based products were main sources, whereas in farm and companion animals, cereal grains, cereal by-products and forage maize contributed most. DON is rapidly absorbed, distributed, and excreted. Since 3-Ac-DON and 15-Ac-DON are largely deacetylated and DON-3-glucoside cleaved in the intestines the same toxic effects as DON can be expected. The TDI of 1 μg/kg bw per day, that was established for DON based on reduced body weight gain in mice, was therefore used as a group-TDI for the sum of DON, 3-Ac-DON, 15-Ac-DON and DON-3-glucoside. In order to assess acute human health risk, epidemiological data from mycotoxicoses were assessed and a group-ARfD of 8 μg/kg bw per eating occasion was calculated. Estimates of acute dietary exposures were below this dose and did not raise a health concern in humans. The estimated mean chronic dietary exposure was above the group-TDI in infants, toddlers and other children, and at high exposure also in adolescents and adults, indicating a potential health concern. Based on estimated mean dietary concentrations in ruminants, poultry, rabbits, dogs and cats, most farmed fish species and horses, adverse effects are not expected. At the high dietary concentrations, there is a potential risk for chronic adverse effects in pigs and fish and for acute adverse effects in cats and farmed mink.

Risks to human and animal health related to the presence of deoxynivalenol and its acetylated and modified forms in food and feed

In recent years, zinc oxide nanoparticles (ZnO NPs) have gained tremendous attention attributed to their unique properties. Notably, evidence has shown that zinc is an important nutrient in living organisms. As such, both prokaryotes and eukaryotes including bacteria, fungi and yeast are exploited for the synthesis of ZnO NPs by using microbial cells or enzyme, protein and other biomolecules compounds in either an intracellular or extracellular route. ZnO NPs exhibit antimicrobial properties, however, the properties of nanoparticles (NPs) are depended upon on their size and shape, which make them specific for various applications. Nevertheless, the desired size and shape of NPs can be obtained through the optimization process of microbes mediated synthesis by manipulating their reaction conditions. It should be noted that ZnO NPs are synthesized by various chemical and physical methods. Nonetheless, these methods are expensive and not environmentally friendly. On that account, the microbes mediated synthesis of ZnO NPs have rapidly evolved recently where the microbes are cleaner, eco-friendly, non-toxic and biocompatible as the alternatives to chemical and physical practices. Moreover, zinc in the form of NPs is more effective than their bulk counterparts and thus, they have been explored for many potential applications including in animals industry. Notably, with the advent of multi-drug resistant strains, ZnO NPs have emerged as the potential antimicrobial agents. This is mainly due to their superior properties in combating a broad spectrum of pathogens. Moreover, zinc is known as an essential trace element for most of the biological function in the animal’s body. As such, the applications of ZnO NPs have been reported to significantly enhance the health and production of the farm animals. Thus, this paper reviews the biological synthesis of ZnO NPs by the microbes, the mechanisms of the biological synthesis, parameters for the optimization process and their potential application as an antimicrobial agent and feed supplement in the animal industry as well as their toxicological hazards on animals.

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Microbial synthesis of zinc oxide nanoparticles and their potential application as an antimicrobial agent and a feed supplement in animal industry: a review

Multiannual mycotoxin survey in feed materials and feedingstuffs

The aim of the present experiment was to investigate the effects of feeding grains naturally contaminated with Fusarium mycotoxins on morphometric indices of jejunum and to follow the passage of deoxynivalenol (DON) through subsequent segments of the digestive tract of broilers. A total of 45 1-d-old broiler chickens (Ross 308 males) were randomly allotted to three dietary treatments (15 birds/treatment): (1) control diet; (2) diet contaminated with 1 mg DON/kg feed; (3) diet contaminated with 5 mg DON/kg feed for five weeks. None of the zootechnical traits (body weight, body weight gain, feed intake, and feed conversion) responded to increased DON levels in the diet. However, DON at both dietary levels (1 mg and 5 mg DON/kg feed) significantly altered the small intestinal morphology. In the jejunum, the villi were significantly (P 0.05) in broilers fed the diet containing DON compared with controls. DON and de-epoxy-DON (DOM-1) were analyzed in serum, bile, liver, feces and digesta from consecutive segments of the digestive tract (gizzard, cecum, and rectum). Concentrations of DON and its metabolite DOM-1 in serum, bile, and liver were lower than the detection limits of the applied liquid chromatography coupled with mass spectrometry (LC-MS/MS) method. Only about 10 to 12% and 6% of the ingested DON was recovered in gizzard and feces, irrespective of the dietary DON-concentration. However, the DON recovery in the cecum as percentage of DON-intake varied between 18 to 22% and was not influenced by dietary DON-concentration. Interestingly, in the present trial, DOM-1 did not appear in the large intestine and in feces. The results indicate that deepoxydation in the present study hardly occurred in the distal segments of the digestive tract, assuming that the complete de-epoxydation occurs in the proximal small intestine where the majority of the parent toxin is absorbed. In conclusion, diets with DON contamination below levels that induce a negative impact on performance could alter small intestinal morphology in broilers. Additionally, the results confirm that the majority of the ingested DON quickly disappears through the gastrointestinal tract.

The impact of the Fusarium mycotoxin deoxynivalenol on the health and performance of broiler chickens.

Summary

We performed a 4-year survey (2006–2009, 1255 samples) of fungal secondary metabolites in feed material (cereal and corn grains) and feedstuffs (silages, mixed feeds). Five major mycotoxin groups were studied, including aflatoxins (AF), ochratoxin A (OTA), trichothecenes [deoxynivalenol (DON), nivalenol (NIV), T-2 toxin, HT-2 toxin], zearalenone (ZEA) and fumonisins (FUM). The metabolites were identified using HPLC methods with fluorescent, UV and MS/MS detection. Both immunoaffinity and SPE columns were used for sample preparation. In eleven samples, the concentration of several mycotoxins exceeded the recommended guidelines for feedstuffs. DON was detected at the highest concentration in the majority of analysed samples (cereal grains, silages and mixed feeds, maximum values ranged from 409 to 14 470 ng/g). Corn grains also contained other Fusarium toxins (FUM) at maximum levels ranging from 435 to 9409 ng/g. The highest averagepositive concentration of the other trichothecenes (NIV, T-2 and HT-2 toxins) was <5.0–139 ng/g. ZEA was found at the highest concentration in corn grains and silages (maximum values ranging from 292 to 603 ng/g and 116 to 1150 ng/g, respectively). The highest averagepositive concentration and the maximum level of OTA were detected in cereal grains (33.0 ng/g in 2009 and 760 ng/g in 2007, respectively). Less than 7% of the 557 samples were contaminated with AF at low levels (maximum of 0.61 ng/g). Our results support the need for further monitoring of mycotoxins in Polish feedstuffs and their components.

Occurrence of mycotoxins in Polish animal feed in years 2006–2009

Deoxynivalenol as a contaminant of broiler feed: Effects on bird performance and response to common vaccines

In vitro biodegradation experiments were done using some probiotic microorganisms. DifferentSaccharomyces cerevisiae, Lactobacilli andBacilli strains were tested for their ability to degrade Nivalenol (NIV), Deoxynivalenol (DON), Diacetoxyscirpenol (DAS), T2-Toxin and Ochratoxin A (OTA). The concentrations of selected mycotoxins were in the range of natural occurring toxin contaminations (1ppm for NIV and DON, 500ppb for DAS and T-2 and 50ppb for OTA). No alteration of concentrations could be registered for the tested trichothecenes. The best results could be achieved in experiments with OTA by up to 94% detoxification. Influence of toxins on colony forming unit of all tested microorganisms were recorded. Especially T-2 toxin and DAS have a slowing effect on growth of some strains.

Jan Grajewski

Papers

Multiannual mycotoxin survey in feed materials and feedingstuffs

The impact of the Fusarium mycotoxin deoxynivalenol on the health and performance of broiler chickens.

Occurrence of mycotoxins in Polish animal feed in years 2006–2009

Deoxynivalenol as a contaminant of broiler feed: Effects on bird performance and response to common vaccines

Study on biodegradation of some A- and B-trichothecenes and ochratoxin A by use of probiotic microorganisms.