The properties that might influence the sequestration of aflatoxin B1 (AfB1) were examined. Laser-diffraction, particle-size analysis (LDPSA) indicated that the particle size of the smectite influences the amount of AfB1 adsorbed. Effective adsorbent smectites disperse well under combined sodium hexametaphosphate solution and ultrasonic agitation. Particle size explained 66% of the variability for most of the samples investigated in an ‘as-received’ state. One effective adsorbent smectite was especially well aggregated and required additional physical dispersion, thus raising the correlation to 73%. Transmission electron microscope (TEM) images show typical smectites and reveal the very diverse morphology of smectites in bentonites. Thin, cloud-like smectite, in TEM images, related positively to AfB1-adsorption capacity. Particles that often fold and are usually ∼0.5 µm across seem to be optimal. The selection of criteria for evaluating these smectites provides a scientific basis for their selection to obtain reliable performance. Particle size is of particular importance as outlined below, and use of LDPSA makes it possible to perform the analysis efficiently and with precision.

Mycotoxins are a major contaminant of pig feed and have negative effects on health and performance. The present study investigated the impact of single or repeated acute challenges with a diet naturally contaminated with deoxynivalenol (DON) and zearalenone (ZEN) on growth performances of finishing pigs and their fecal microbiota composition. A total of 160 pigs (castrated males and females) in two successive batches were randomly divided into four experimental groups of 40 pigs each. The control group received a control finisher diet from 99 to 154 days of age. Challenged groups were subjected to a 7-day acute challenge by being fed a DON- and ZEN-contaminated diet (3.02 mg DON/kg feed and 0.76 mg ZEN/kg feed) at 113 days (group DC), 134 days (group CD) or both 113 and 134 days (group DD). Microbiota composition was analyzed via 16S rRNA sequencing from fecal samples collected from the 80 females at 99, 119, 140 and 154 days. Challenged pigs (i.e. groups DC, CD and DD) reduced their average daily feed intake by 25% and 27% (P < 0.001) and feed efficiency by 34% and 28% (P < 0.05) during the first and second mycotoxin exposure, respectively. Microbiota composition was affected by mycotoxin exposure (P = 0.07 during the first exposure and P = 0.01 during the second exposure). At the family level, mycotoxin exposure significantly (P < 0.05) decreased the relative abundances of Ruminococcaceae, Streptococcaceae and Veillonellaceae and increased that of Erysipelotrichaceae at both 119 and 140 days of age. After the 7-day DON/ZEN challenge, the relative abundance of 6 to 148 operational taxonomic units (OTUs) differed among the treatment groups. However, none of these OTUs changed in all treatment groups. Using 27 functional pathways, pigs exposed to DON/ZEN challenges could be distinguished from control pigs using sparse partial least squares discriminant analysis, with a 15% misclassification rate. Regarding the functionality of these predictors, two pathways were involved in detoxifying mycotoxins: drug metabolism and xenobiotic metabolism by cytochrome P450. In challenged pigs, microbiota composition returned to the initial state within 3 weeks after the end of a single or repeated DON/ZEN challenge, highlighting the resilience of the gut microbiome. The feeding and growth performances of the pigs during challenge periods were significantly correlated with biological pathways related to health problems and modifications in host metabolism. To conclude, short-term DON/ZEN challenges resulted in transient modifications in the composition and functions of fecal microbiota.

Ochratoxin A (OTA) is a mycotoxin produced by various species of Aspergillus and Penicillium. Ochratoxin A was classified as a group 2B carcinogen and is one of the major intestinal pathogenic mycotoxins. One of the most frequent modes of intoxication is consumption of contaminated food with mycotoxins. Feed represents the major cost and has a direct impact on the economical viability of broiler’s production system, since it must contain the necessary elements that allow the animal to express the maximum genetic potential while providing its nutritional requirements. Thus, the animal has to digest the feed and absorb its nutrients, which is in direct correlation with the gastrointestinal tract, especially the small intestine and the development of the mucosal surface area. Once ingested, OTA is absorbed by passive diffusion, mainly the jejunum. Ochratoxin A’s presence affects lipid membranes and could lead to the degradation of their normal structure and functionality. All of these effects contribute to the development of malabsorption. It was very interesting to study the effect of OTA on the layer of phospholipids of the bowel. The experimental group received OTA (0.05 to mg/kg BW) through an intra-peritoneal injection, every other day for 21 days. We noted that feed conversion ratio and average daily gain were reduced. Histological studies showed important alterations at the level of the mucosal membrane of the intestine (villosities, crypts) following intra-peritoneal administration of the mycotoxin. Thinning and enlargement at the base of the villosities, hyperplasia and crypts in irregular forms, blunting and denudation were observed through the examination of intestinal morphology. Biochemical studies, such as total lipid and phospholipid compositions, allowed us to have more detailed results. All identified mucosal phospholipids were modified, particularly the phosphatidylcholine (PC) and the phosphatidylethanolamine (PE) in the jejunum mucosa. In fact, there was a decrease by 55.81% for PC, 56.66% for PE, while a significant increase by 32.91% was noted for phosphatidylserine in the jejunum. It was very interesting to study the effect of OTA on the phospholipids layer of the bowel, as the mucous membrane of the small intestine represents the main site of absorption and transformation of nutriments. To avoid such disturbances and prevent the effects of the OTA, precautions must be taken to inhibit mold growth at the level of the feed manufactory units. Phosphatidylcholine and PE administrations may represent an option that could allow reestablishment of phospholipid equilibrium in the intestine.

Vitamins play an essential role in broiler nutrition. They are fundamental for normal metabolic and physiological process, and their requirements for poultry are not fixed and can be affected by multiple factors. In contrast, mycotoxins are a challenging issue because they hinder performance and the immune system. Vitamin supplementation above minimum requirements would permit improvement in productive potential, health, bone and meat quality in a situation of mycotoxin challenge. The objective of this study was to determine the influence of optimum vitamin nutrition in diets contaminated with aflatoxin in broilers from 1 to 44 days of age. A total of 1800 Cobb 500 male chicks were randomized to 15 sets of eight treatment groups, each containing 15 birds using a 2 × 2 × 2 factorial design (commercial vitamin levels and high vitamin levels, two levels of aflatoxin – 0 and 0.5 ppm with binder levels of 0 and 10 000 mg/kg). The mash diets were corn and soybean meal based, formulated according to commercial practices. Feed intake, weight gain and feed conversion were analyzed for birds from 1 to 44 days of age. To determine carcass characteristics (carcass yield, breast yield and leg yield) and black bone syndrome, two birds were slaughtered from each group at 45 days. Other analyses included breast tenderness, water loss by dripping and malonaldehyde concentrations. The results demonstrated that broilers that were fed high levels of vitamins showed better weight gain, feed conversion, carcass yield and breast yield than broilers that were fed diets with commercial vitamin levels (P < 0.05); also, broilers that were fed diets containing 0.5 ppm aflatoxin had lower weight gain, carcass yield and breast yield (P < 0.05). The use of 10 000 mg/kg of binder improved (P < 0.05) feed conversion throughout the rearing period. We conclude that aflatoxin negatively affects performance and carcass yield; however, feeding optimum vitamin nutrition improved these performance traits.

Fumonisin B1 (FB1) sprayed on intact jimsonweed plants at 10 to 200 μg ml–1 caused chlorosis and necrosis on three- to four-leaf plants and reduced their height and biomass. Excised leaves of jimsonweed were necrotic on both surfaces after treatment with FB1 at 10 to 200 μg ml–1. The degree of damage increased with the concentration of FB1. The minimum amount of FB1 that damaged excised leaves was 0.05 μg. The symptoms of toxicity on sensitive plants varied with concentration of FB1. Symptoms observed included: chlorosis (creeping cucumber), necrosis (jimsonweed and common sunflower), black leaf lesions (sicklepod), curl of tissues (soybean), stunting, defoliation (hemp sesbania and northern jointvetch), and death (prickly sida, spurred anoda, northern jointvetch, and jimsonweed). Monocots (barley, bermudagrass, corn, johnsongrass, rice, sorghum, and wheat) were not visibly affected by FB1. This is the first evidence of the phytotoxic properties of fumonisin B1 against a wide variety of weeds and crop cultivars.

Necrotic enteritis (NE) has become one of the most important diseases of modern global poultry production, with an estimated cost of around US$6 billion per annum in lost production and control strategies. The rise in prominence of NE is attributed to the prohibition of antibiotics as growth promoters (AGP) or the voluntary implementation of ‘drug-free’ broiler production programmes. Pathogenic strains of Clostridium perfringens are responsible for NE, with those expressing the NetB toxin a definitive cause in disease models. C. perfringens are normal inhabitants of the gastrointestinal tract (GIT) but these are typically non-pathogenic strains. When intestinal health is compromised, the prevailing conditions allow the establishment and proliferation of pathogenic, toxin-secreting strains of C. perfringens. The toxin(s) damages the intestinal epithelium and causes disease. Certain dietary-related factors are recognised as predisposing poultry to NE. This review will focus on the key initiators of NE and will outline the most appropriate strategies to counteract these predisposing factors and prevent NE. The continual push, globally, for poultry production programmes with less antibiotic use will sustain NE as an important and costly poultry disease that requires dietary intervention.

Coronatin-2, a 14.5 kDa protein, was isolated from culture filtrates of the entomopathogenic fungus Conidiobolus coronatus (Costantin) Batko (Entomophthoramycota: Entomophthorales). After LC–MS/MS (liquid chromatography tandem mass spectrometry) analysis of the tryptic peptide digest of coronatin-2 and a mass spectra database search no orthologs of this protein could be found in fungi. The highest homology was observed to the partial translation elongation factor 1a from Sphaerosporium equinum (protein sequence coverage, 21%), with only one peptide sequence, suggesting that coronatin-2 is a novel fungal protein that has not yet been described. In contrast to coronatin-1, an insecticidal 36 kDa protein, which shows both elastolytic and chitinolytic activity, coronatin-2 showed no enzymatic activity. Addition of coronatin-2 into cultures of hemocytes taken from larvae of Galleria mellonella Linnaeus (Lepidoptera: Pyralidae), resulted in progressive disintegration of nets formed by granulocytes and plasmatocytes due to rapid degranulation of granulocytes, extensive vacuolization of plasmatocytes accompanied by cytoplasm expulsion, and cell disintegration. Spherulocytes remained intact, while oenocytes rapidly disintegrated. Coronatin-2 produced 80% mortality when injected into G. mellonella at 5 µg larva−1. Further study is warranted to determine the relevance of the acute toxicity of coronatin-2 and its effects on hemocytes in vitro to virulence of C. coronatus against its hosts.

The aim of this trial was to assess the effects of the administration of different combinations of mycotoxins in naturally contaminated maize grains on dairy heifer growth, blood measurements and puberty onset. A total of 35 Friesian female heifers were randomly allotted to three experimental groups from 18–21 to 42–45 weeks of age. During the 24-week experimental period (EP), heifers were fed the same diet, but with maize meal derived from three differently contaminated lots: very low contamination, as control (C); medium–low aflatoxin-contaminated (A); and mixed aflatoxin–fumonisin contaminated (A-F). At the end of the EP, they returned to a common diet without contaminated maize, and they were monitored for an additional period of 12 weeks (post-experimental period, PEP). BW, wither height, hip height, body length and heart girth were measured every 4 weeks from the beginning of EP to the end of PEP. At the same time, body condition score was evaluated and blood samples were taken from the jugular vein to be analysed for haematological, serum protein and metabolic profiles. Age at puberty was assessed by measuring weekly plasma progesterone levels from 40 to 52 weeks of age. Body growth measurements were processed both by ANOVA of average daily gain of EP and PEP separately, and by the analysis of growth curve parameters. Haematological, serum protein and metabolic profile were evaluated using a mixed model, taking into account the repeated measurements in time on each animal. Heifers’ growth was delayed both in A and A-F groups during EP, as evidenced by the different linear coefficients of the BW growth curve in the three groups. Differently contaminated diets did not affect the haematological profile, so that it can be concluded that these levels of mycotoxin contamination do not determine any specific effect on haematopoiesis and immunity in growing heifers. The main blood marker of mycotoxin chronic toxicity was the γ-glutamyl transferase activity level in plasma, which appeared to be altered even after the removal of mycotoxins. During EP, plasma glucose was lower in the groups fed contaminated diet compared with C. The joint actions of an altered nutritional status and a long-lasting liver damage were probably the causes of the delay in puberty attainment in A and, particularly, in the A-F group. The results from this trial evidenced that a chronic aflatoxin–fumonisin contamination in diets of dairy heifers can determine an important delay in the reproductive career of these animals.

Mycotoxins, such as aflatoxin (AF), fumonisin B1, zearalenone (ZEA), and deoxynivalenol (DON), are commonly found in many food commodities. Mycotoxins have been shown to increase DNA methylation levels in a human intestinal cell line. We previously showed that the developmental competence of oocytes was affected in mice that had been fed a mycotoxin-containing diet. In this study, we explored possible mechanisms of low mouse oocyte developmental competence after mycotoxin treatment in an epigenetic modification perspective. Mycotoxin-contaminated maize (DON at 3,875 μg/kg, ZEA at 1,897 μg/kg, and AF at 806 μg/kg) was included in diets at three different doses (mass percentage: 0, 15, and 30%) and fed to mice for 4 weeks. The fluorescence intensity analysis showed that the general DNA methylation levels increased in oocytes from high dose mycotoxin-fed mice. Mouse oocyte histone methylation was also altered. H3K9me3 and H4K20me3 level increased in oocytes from mycotoxin-fed mice, whereas H3K27me3 and H4K20me2 level decreased in oocytes from mycotoxin-fed mice. Thus, our results indicate that naturally occurring mycotoxins have effects on epigenetic modifications in mouse oocytes, which may be one of the reasons for reduced oocyte developmental competence.

A dairy cow model was established to measure the transmission of aflatoxin M1 (AFM1) into milk. Four Ayrshire mid-lactation dairy cows (ranging 590 – 650 kg body weight and averaging 4.5 years of age) were used in a crossover experimental design in which each cow acted as its own control and was subjected to four dietary treatments administered as six 12-day feeding periods followed by a 7-day washout period. Periods I – VI comprised a 7 d of adaptation followed by 5 d of sampling. Period VII was a 7-d washout with sampling in the final two days. From each morning's milking, yield was recorded and sampled for AFM1 analysis by HPLC. Treatments included a negative control, contamination with AFB1 (5 µg of AFB1/kg feed), AFB1 + Mycosorb® (MTB) 10 g/cow/d, and AFB1 + MTB 50 g/cow/d. In response to the negative control, AFM1 concentrations in milk remained below the limit of detection (<5 ng/kg), whereas cows fed the AFB1-contaminated feed had milk AFM1 concentrations ranging from 110 to 230 ng/kg. At the end of the washout period, AFM1 was again undetectable. The dairy cow model was also used to test the efficacy of the yeast-cell-wall-based mycotoxin binder Mycosorb® (MTB) in reducing secretion of AFM1 into milk by cows fed the same AFB1-contaminated diet. When supplemented at 50 g/head/day, MTB significantly reduced (P < 0.05) AFM1 secretion into milk with no adverse effects on milk production. The dairy cow model is a sensitive tool for measuring aflatoxin transmission to milk and mycotoxin binder efficacy at 5 µg of AFB1/kg feed. As it is common for on-farm AFB1 concentrations to exceed 5 µg/kg, more research may be warranted to determine the effectiveness of the model at higher AFB1 concentrations.

A pilot study was conducted to evaluate the suitability of hepatic aflatoxin (AFB1) concentration as a biomarker to assess the in vivo efficacy of a mycotoxin binder in poultry when AFB1 dietary concentrations are low. Diets containing low doses of AFB1 without or with Mycosorb® (MTB), a mycotoxin binder, were fed to broilers from 7 to 21 days of age. The accumulation of AFB1 in liver was measured by high performance liquid chromatography with a detection limit of 5 ng/kg liver. In response to 10 and 50 µg AFB1/kg feed, hepatic AFB1 accumulation was 27 and 145 ng AFB1/kg liver, respectively. At each dietary concentration of AFB1, the inclusion of 5 g MTB/kg of feed reduced (P < 0.1 for 10 μg AFB1/kg feed and P < 0.05 for 50 μg AFB1/kg feed) hepatic AFB1 accumulation by at least 50%. These results suggest that hepatic AFB1 concentration is a suitable biomarker for evaluating mycotoxin binder efficacy in poultry fed the EU maximum dietary concentration of 10 µg of AFB1/kg feed.

Mycotoxins are toxic secondary metabolites that globally contaminate an estimated 25 % of cereal crops and thus exposure is frequent in many populations. Aflatoxins, fumonisins and deoxynivalenol are amongst those mycotoxins of particular concern from a human health perspective. A number of risks to health are suggested including cancer, growth faltering, immune suppression and neural tube defects; though only the demonstrated role for aflatoxin in the aetiology of liver cancer is widely recognised. The heterogeneous distribution of mycotoxins in food restricts the usefulness of food sampling and intake estimates; instead biomarkers provide better tools for informing epidemiological investigations. Validated exposure biomarkers for aflatoxin (urinary aflatoxin M1, aflatoxin–N7-guaunine, serum aflatoxin–albumin) were established almost 20 years ago and were critical in confirming aflatoxins as potent liver carcinogens. Validation has included demonstration of assay robustness, intake v. biomarker level, and stability of stored samples. More recently, aflatoxin exposure biomarkers are revealing concerns of growth faltering and immune suppression; importantly, they are being used to assess the effectiveness of intervention strategies. For fumonisins and deoxynivalenol these steps of development and validation have significantly advanced in recent years. Such biomarkers should better inform epidemiological studies and thus improve our understanding of their potential risk to human health.

The present study was conducted to follow up on apparent differences in growth, relative organ sizes, cellular stress and immune function in Atlantic salmon fed feed containing GM Bacillus thuringiensis maize compared with feed containing the non-modified parental maize line. Gene expression profiling on the distal intestinal segment and liver was performed by microarray, and selected genes were followed up by quantitative PCR (qPCR). In the liver, qPCR revealed some differentially regulated genes, including up-regulation of gelsolin precursor, down-regulation of ferritin heavy subunit and a tendency towards down-regulation of metallothionein (MT)-B. This, combined with the up-regulation of anti-apoptotic protein NR13 and similar tendencies for ferritin heavy chain and MT-A and -B in the distal intestine, suggests changes in cellular stress/antioxidant status. This corresponds well with and strengthens previous findings in these fish. To exclude possible confounding factors, the maize ingredients were analysed for mycotoxins and metabolites. The GM maize contained 90 μg/kg of deoxynivalenol (DON), while the non-GM maize was below the detection limit. Differences were also observed in the metabolite profiles of the two maize varieties, some of which seemed connected to the mycotoxin level. The effects on salmon observed in the present and previous studies correspond relatively well with the effects of DON as reported in the literature for other production animals, but knowledge regarding effects and harmful dose levels in fish is scarce. Thus, it is difficult to conclude whether the observed effects are caused by the DON level or by some other aspect of the GM maize ingredient.

Fungi may develop in stored grains following field inoculation. In the course oftheir development fungi utilize plant nutrients, contributing to a reduction in their content. This reduction is obviously related to the degree of fungi development, but may become relevant in extreme cases. During the process of host colonization fungi may also produce toxins that are harmful for humans and animals. This occurs mainly under specific conditions of plant stress, such as those produced by adverse weather conditions, for instance drought has been shown to prompt aflatoxin production in peanuts. Differences in mycotoxin production are also related to plant genotype. Aflatoxin B1 produced by Aspergillus flavus is the most carcinogenic natural substance known. It is frequently charged with the reduction in performance of domestic birds, even when its concentration in the feed is very low. Approaches to eliminate mycotoxins from contaminated grains are not always worthwhile in practical and economical terms. Strategies used to reduce mycotoxin levels in cereal grains include the dilution of infected with healthier grains or the addition of adsorbents to the feeds. Several compounds such as activated charcoal, aluminosilicates and processed cell wall of Saccharomyces sp. (esterified glucomannan) have shown to be effective as mycotoxin adsorbents in poultry feeds. Adsorbent effectiveness has been reported with in vitro and in vivo techniques; however, it is still very difficult to quantify their benefits in commercial operations.

Prevention and control of mycotoxins in the poultry production chain requires the knowledge and consideration of all factors influencing mycotoxin formation in the field and during the storage of feedstuffs. Mycotoxin effects on health and performance of poultry and the ‘carry over’ of mycotoxins or their metabolites into foodstuffs of animal origin are also essential information elements.

Among a number of known my cotoxins, the Fusarium-mycotoxins deoxynivalenol (DON) and zearalenone (ZON) are of special importance under European production conditions because of their high frequency and concentrations. Several plant production strategies might help to minimize the risk of formation of these mycotoxins. However, higher mean values are unavoidable under unfavourable weather conditions. Therefore, special care must be taken in so-called ‘Fusurium-years’, because poultry is regarded as less sensitive to these mycotoxins than pigs and suspect cereal batches will be diverted to poultry feeding.

Higher dietary DON-concentrations adversely affect the performance and immune response of poultry at dietary concentrations of greater than 5 mg per kg diet. In contrast, zearalenone, which often co-occurs with DON, does not cause deleterious effects in poultry even in ‘Fusurium-years’ when higher concentrations are measured. ‘Carry over’ of both toxins into poultry products is very low and is negligible when the DON-concentration of the diet is restricted to this 5 mg per kg.

The levels of further Fusurium mycotoxins such as T-2 toxin, fumonisins, moniliformin or beauvericin to be expected in Europe are too low to cause toxic effects in poultry. However, several combinations of co-occurring mycotoxins might influence the total toxic potential of a contaminated feedstuff.

Several feed-processing procedures are suitable for reducing the DON-content of contaminated feedstuffs, but they are expensive or have been only lab-tested. Adsorbing agents were shown to either only weakly bind DON, or not to bind it at all in vitro, and to be ineffective in vivo. More recent efforts have been directed at employing the capability of several micro-organisms (bacteria and yeasts) to degrade DON for detoxification in situ.