Occurrence of mycotoxins in feed ingredients and complete feeds obtained from the Beijing region of China

Nutrition strategies to control post-weaning diarrhea of piglets: From the perspective of feeds

Post-weaning diarrhea (PWD) is a globally significant threat to the swine industry. Historically, antibiotics as well as high doses of zinc oxide and copper sulfate have been commonly used to control PWD. However, the development of bacterial resistance and environmental pollution have created an interest in alternative strategies. In recent years, the research surrounding these alternative strategies and the mechanisms of piglet diarrhea has been continually updated. Mechanically, diarrhea in piglets is a result of an imbalance in intestinal fluid and electrolyte absorption and secretion. In general, enterotoxigenic Escherichia coli (ETEC) and diarrheal viruses are known to cause an imbalance in the absorption and secretion of intestinal fluids and electrolytes in piglets, resulting in diarrhea when Cl- secretion-driven fluid secretion surpasses absorptive capacity. From a perspective of feedstuffs, factors that contribute to imbalances in fluid absorption and secretion in the intestines of weaned piglets include high levels of crude protein (CP), stimulation by certain antigenic proteins, high acid-binding capacity (ABC), and contamination with deoxynivalenol (DON) in the diet. In response, efforts to reduce CP levels in diets, select feedstuffs with lower ABC values, and process feedstuffs using physical, chemical, and biological approaches are important strategies for alleviating PWD in piglets. Additionally, the diet supplementation with additives such as vitamins and natural products can also play a role in reducing the diarrhea incidence in weaned piglets. Here, we examine the mechanisms of absorption and secretion of intestinal fluids and electrolytes in piglets, summarize nutritional strategies to control PWD in piglets from the perspective of feeds, and provide new insights towards future research directions.

Early-life exposure to mycotoxin zearalenone exacerbates aberrant immune response, oxidative stress, and mortality of Caenorhabditis elegans under pathogen Bacillus thuringiensis infection

Zearalenone (ZEN) is a prevalent mycotoxin that severely impacts human and animal health. However, the possible interactions between ZEN exposure, pathogen infection, immune system, and reactive oxygen species (ROS) were rarely investigated. We studied the effects of early-life ZEN (50 µM) exposure on the immune response of Caenorhabditis elegans against Bacillus thuringiensis infection and the associated mechanisms. The transcriptomic responses of C. elegans after early-life ZEN exposure were investigated using RNA sequencing and followed by verification using quantitative PCR analysis. We also investigated the immune responses of the worms through B. thuringiensis killing assays and by measuring oxidative stress. The transcriptomics result showed that early-life exposure to ZEN resulted in 44 differentially expressed genes, 7 of which were protein-coding genes with unknown functions. The Gene Ontology analysis suggested that metabolic processes and immune response were among the most significantly enriched biological processes, and the KEGG analysis suggested that lysosomes and metabolic pathways were the most significantly enriched pathways. The ZEN-exposed worms exhibited significantly reduced survival after 24-h B. thuringiensis infection, reaching near 100% mortality compared to 60% of the controls. Using qRT-PCR assay, we found that ZEN further enhanced the expression of immunity genes lys-6, spp-1, and clec-60 after B. thuringiensis infection. A concurrently enhanced ROS accumulation was also observed for ZEN-exposed worms after B. thuringiensis infection, which was 1.2-fold compared with the controls. Moreover, ZEN exposure further enhanced mRNA expression of catalases (ctl-1 and ctl-2) and increased catalase protein activity after B. thuringiensis exposure compared with their non-exposed counterparts, suggesting an elevated oxidative stress. This study suggests that early-life exposure to mycotoxin zearalenone overstimulates immune responses involving spp-17, clec-52, and clec-56, resulting in excessive ROS production, enhanced oxidative stress as indicated by aggravated ctl expression and activity, and a decline in host resistance to pathogenic infection which ultimately leads to increased mortality under B. thuringiensis infection. Our findings provide evidence that could improve our understanding on the potential interactions between mycotoxin zearalenone and pathogens.

Mycotoxins in Cereal-Based Products and Their Impacts on the Health of Humans, Livestock Animals and Pets

Cereal grains are the most important food staples for human beings and livestock animals. They can be processed into various types of food and feed products such as bread, pasta, breakfast cereals, cake, snacks, beer, complete feed, and pet foods. However, cereal grains are vulnerable to the contamination of soil microorganisms, particularly molds. The toxigenic fungi/molds not only cause quality deterioration and grain loss, but also produce toxic secondary metabolites, mycotoxins, which can cause acute toxicity, death, and chronic diseases such as cancer, immunity suppression, growth impairment, and neural tube defects in humans, livestock animals and pets. To protect human beings and animals from these health risks, many countries have established/adopted regulations to limit exposure to mycotoxins. The purpose of this review is to update the evidence regarding the occurrence and co-occurrence of mycotoxins in cereal grains and cereal-derived food and feed products and their health impacts on human beings, livestock animals and pets. The effort for safe food and feed supplies including prevention technologies, detoxification technologies/methods and up-to-date regulation limits of frequently detected mycotoxins in cereal grains for food and feed in major cereal-producing countries are also provided. Some important areas worthy of further investigation are proposed.

Toxicokinetics of Deoxynivalenol in Dezhou Male Donkeys after Oral Administration

Deoxynivalenol (DON) is detected in different types of foods and feeds, inducing toxicity in humans and animals. After entering the organism, DON first appears in the plasma; then, it is rapidly absorbed and distributed in various organs and tends to accumulate in the body to exert its toxic effects. This study was performed to investigate the toxicokinetics of DON on Dezhou male donkeys after a single oral dose of 500 μg/kg·BW (body weight). The plasma of donkeys was collected at 0, 5, 10, 15, 20, 30, 45 min, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 6, 9, 12, 24, 48, 72, 96 and 120 h after administration, and the feces and urine were collected at 0 h and at 6 h intervals up to 24 h, followed by 4 h intervals up to 120 h. The concentrations of DON in plasma, urine and feces were determined by HPLC. The peak concentration of DON in plasma was 174.30 μg/L, which occurred at 1.07 h after oral gavage. The recovery of unchanged DON in urine and feces amounted to 19.98% and 6.74%, respectively. Overall, DON was rapidly absorbed and slowly eliminated in donkeys within 120 h following a single oral dose, which can lead to DON accumulation in the body if ingested for a long time.

Lactational exposure to Deoxynivalenol causes mammary gland injury via inducing inflammatory response and impairing blood-milk barrier integrity in mice

Lactation is a unique physiological process to produce and secrete milk. Deoxynivalenol (DON) exposure during lactation has been demonstrated to affect adversely the growth development of offspring. However, the effects and potential mechanism of DON on maternal mammary glands remain largely unknown. In this study, we found the length and area of mammary glands were significantly reduced after DON exposure on lactation day (LD) 7 and LD 21. RNA-seq analysis results showed that the differentially expressed genes (DEGs) were significantly enriched in acute inflammatory response and HIF-1 signaling pathway, which led to an increase of myeloperoxidase activity and inflammatory cytokines. Furthermore, lactational DON exposure increased blood-milk barrier permeability by reducing the expression of ZO-1 and Occludin, promoted cell apoptosis by upregulating the expression of Bax and cleaved Caspase-3 and downregulating the expression of Bcl-2 and PCNA. Additionally, lactational DON exposure significantly decreased serum concentration of prolactin, estrogen, and progesterone. All these alterations eventually resulted in a decrease of β-casein expression on LD 7 and LD 21. In summary, our findings indicated that lactational exposure to DON caused lactation-related hormone disorder and mammary gland injury induced by inflammatory response and blood-milk barrier integrity impairment, ultimately resulting in lower production of β-casein.

The N-terminal hydrophobicity modulates a distal structural domain conformation of zearalenone lacton hydrolase and its application in protein engineering

Zearalenone (ZEN) is one of the most common mycotoxins in maize, wheat, barley, sorghum, rye and other grains. ZEN contamination in feed is an international health issue due to its estrogenicity by competitively binding to estrogen receptors. Enzymatic detoxification of ZEN is superior to physical and chemical methods in terms of safety, environmental impact and preserving nutritional value and palatability, but is hampered by both the currently limited repertoire of detoxifying enzymes and the lack of knowledge about their structure-function relationships. In this study, a ZEN lacton hydrolase candidate (ZHD11C) was identified from thermo-tolerant Fonsecaea multimorphosa CBS 102226, and characterized to be more thermostable than these reported homologues. An intriguing feature of ZHD11C is that the N-terminal hydrophobicity affects its thermal stability and causes conformational change of a domain far from the N-terminal. This finding was successfully applied to enhance the thermostability of the most active ZEN lacton hydrolase ZHD518 through rationally tailoring its N-terminal hydrophobicity. Our results not only provide more insights into the structure-function relationships of ZEN lacton hydrolases, but generate better candidate for bio-decontamination of zearalenone in feed industries.

Mycosorb A+® como adsorbente de micotoxinas en la dieta sobre la salud y la producción en cuyes

Los alimentos destinados a los animales están contaminados por hongos filamentosos que producen micotoxinas. El estudio tuvo como objetivo evaluar el efecto de Mycosorb A+® como adsorbente de micotoxinas en la dieta sobre la salud, producción y beneficio económico de cuyes en crianza comercial. Se utilizaron 80 cuyes en crecimiento de la raza Perú, entre machos y hembras, con un peso de 435,5 ± 35,5 gramos (g), distribuidos al azar en dos grupos de alimentación: dieta con Mycosorb A+® (experimental) y dieta sin Mycosorb A+® (control), realizado en el distrito de Ilabaya-Tacna, Perú, a 1.425 metros de altitud, durante 57 días. La dieta se elaboró con heno molido de alfalfa, maíz amarillo, afrecho de trigo, torta de soya, harina integral de soya y fuentes de minerales y vitaminas, ofrecida para consumo ad libitum, más 12,5 g·día-1 de alfalfa fresca (H° 78 %) por cuy. Los resultados indican que todas las variables evaluadas, excepto el consumo de materia seca, fueron significativas (P<0,05): morbilidad 2,5 vs. 35,0 %; consumo de materia seca, 59,8 ± 2,1 vs. 58,0 ± 2,4 g·día-1; ganancia de peso vivo, 9,7 ± 1,4 vs. 7,8 ± 0,9 g·día-1; conversión alimenticia, 6,3 ± 0,9 vs. 7,5 ± 0,6; y relación beneficio-costo, 1,52 vs. 1,35, respectivamente. Se concluye que la inclusión de Mycosorb A+® como adsorbente de micotoxinas en la dieta tiene efecto positivo en la salud, producción y beneficio económico en la crianza comercial de cuyes.

Taurine alleviates ochratoxin A-induced pyroptosis in PK-15 cells by inhibiting oxidative stress

Ochratoxin A (OTA) is one of the most harmful mycotoxins, which can cause multiple toxicological effects, especially nephrotoxicity in animals and humans. Taurine is an essential amino acid with various biological functions such as anti-inflammatory and anti-oxidation. However, the protective effect of taurine on OTA-induced nephrotoxicity and pyroptosis had not been reported. Our results showed that OTA exposure induced cytotoxicity and oxidative stress in PK-15 cells, including reactive oxygen species (ROS) accumulation, increased mRNA levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase 2 (COX-2), and decreased mRNA levels of catalase (CAT), glutathione peroxidase 1 (GPx1), and glutathione peroxidase 4 (GPx4). In addition, OTA treatment induced pyroptosis by increasing the expressions of pyroptosis-related proteins NLRP3, GSDMD, Caspase-1 P20, ASC, Pro-caspase-1, and IL-1β. Meanwhile, taurine could alleviate OTA-induced pyroptosis and cytotoxicity, as well as reduce ROS level, COX-2, and iNOS mRNA levels, and increase the mRNA levels of the antioxidant enzyme in PK-15 cells. Taken together, taurine alleviated OTA-induced pyroptosis in PK-15 cells by inhibiting ROS generation and altering the activity of antioxidant enzymes, thereby attenuating its nephrotoxicity.

An Efficient HPLC-PDA Coupled With Supel™ Tox DON SPE Approach for the Analysis of Deoxynivalenol Contamination in Cereal Grains and Feedstuffs in Jiangxi Province

Deoxynivalenol (DON) was commonly found in grains and feedstuffs, which can cause human chronic diseases. In this study, a quick and reliable method was developed for the determination of DON in grains and feedstuffs in Jiangxi Province market. The sample was extracted with acetonitrile-water (84:16, v/v), then purified by Supel™ Tox DON SPE column, and detected by high-performance liquid chromatography (HPLC). The results showed that the calibration curve of DON showed good linearity in the range of 0.01-10.0 μg/mL, and the correlation coefficient R² = 0.9999. The recovery of DON in the spiked maize sample was 94.8-98.5% by spiking with DON at 0.2 µg/g, 1.0 µg/g, and 2.0 µg/g. The RSD was between 2.5 and 3.3%. This method was used to analyze 120 samples, including 90 grains and 30 feedstuffs, collected from the Jiangxi Province market. The results showed that 81 samples of grains were positive with 90.0% positive rates, and 30 samples of feedstuff were positive with 100% positive rates. Maximum concentration of DON was 0.7 μg/g in oat and 6.9 μg/g in wheat feedstuffs, respectively. Fortunately, the positive samples of grains were safe levels in comparison with National standards for food safety limits of mycotoxins in food (1.0 μg/g), while, the feedstuff of oats was over the Maximum Guideline Level of 16.7% (the Maximum Residue Limit, MRL is 5.0 μg/g). The results of this study about current DON pollution in the grains and feedstuffs on the Jiangxi Province market have not been previously reported.

Aflatoxins in Feed: Types, Metabolism, Health Consequences in Swine and Mitigation Strategies

Feeding farm animals with aflatoxin-contaminated feed can cause various severe toxic effects, leading to increased susceptibility to infectious diseases and increased mortality, weight loss, poor performance and reduced reproductive capability. Following ingestion of contaminated foodstuffs, aflatoxins are metabolized and biotransformed differently in animals. Swine metabolism is not effective in detoxifying and excreting aflatoxins, meaning the risk of aflatoxicosis is increased. Thus, it is of great importance to elucidate the metabolism and all metabolic pathways associated with this mycotoxin. The damage induced by AFB1 in cells and tissues consists of inhibition of cell proliferation, carcinogenicity, immunosuppression, mutagenicity, oxidative stress, lipid peroxidation and DNA damage, leading to pathological lesions in the liver, spleen, lymph node, kidney, uterus, heart, and lungs of swine. At present, it is a challenging task and of serious concern to completely remove aflatoxins and their metabolites from feedstuff; thus, the aim of this study was a literature review on the deleterious effects of aflatoxins on swine metabolism, as well as alternatives that contribute to the detoxification or amelioration of aflatoxin-induced effects in farm animal feed.

Dietary Catalase Supplementation Alleviates Deoxynivalenol-Induced Oxidative Stress and Gut Microbiota Dysbiosis in Broiler Chickens

Catalase (CAT) can eliminate oxygen radicals, but it is unclear whether exogenous CAT can protect chickens against deoxynivalenol (DON)-induced oxidative stress. This study aimed to investigate the effects of supplemental CAT on antioxidant property and gut microbiota in DON-exposed broilers. A total of 144 one-day-old Lingnan yellow-feathered male broilers were randomly divided into three groups (six replicates/group): control, DON group, and DON + CAT (DONC) group. The control and DON group received a diet without and with DON contamination, respectively, while the DONC group received a DON-contaminated diet with 200 U/kg CAT added. Parameter analysis was performed on d 21. The results showed that DON-induced liver enlargement (p < 0.05) was blocked by CAT addition, which also normalized the increases (p < 0.05) in hepatic oxidative metabolites contents and caspase-9 expression. Additionally, CAT addition increased (p < 0.05) the jejunal CAT and GSH-Px activities coupled with T-AOC in DON-exposed broilers, as well as the normalized DON-induced reductions (p < 0.05) of jejunal villus height (VH) and its ratio for crypt depth. There was a difference (p < 0.05) in gut microbiota among groups. The DON group was enriched (p < 0.05) with some harmful bacteria (e.g., Proteobacteria, Gammaproteobacteria, Enterobacteriales, Enterobacteriaceae, and Escherichia/Shigella) that elicited negative correlations (p < 0.05) with jejunal CAT activity, and VH. DONC group was differentially enriched (p < 0.05) with certain beneficial bacteria (e.g., Acidobacteriota, Anaerofustis, and Anaerotruncus) that could benefit intestinal antioxidation and morphology. In conclusion, supplemental CAT alleviates DON-induced oxidative stress and intestinal damage in broilers, which can be associated with its ability to improve gut microbiota, aside from its direct oxygen radical-scavenging activity.

The evolution of multiplex detection of mycotoxins using immunoassay platform technologies

Mycotoxins present serious threats not only for public health, but also for the economy and environment. The problems become more complex and serious due to co-contamination of multiple hazardous mycotoxins in commodities and environment. To mitigate against this issue, accurate, affordable, and rapid multiplex detection methods are required. This review presents an overview of emerging rapid immuno-based multiplex methods capable of detecting mycotoxins present in agricultural products and feed ingredients published within the past five years. The scientific principles, advantages, disadvantages, and assay performance of these rapid multiplex immunoassays, including lateral flow, fluorescence polarization, chemiluminescence, surface plasmon resonance, surface enhanced Raman scattering, electrochemical sensor, and nanoarray are discussed. From the recent literature landscape, it is predicted that the future trend of the detection methods for multiple mycotoxins will rely on the advance of various sensor technologies, a variety of enhancing and reporting signals based on nanomaterials, rapid and effective sample preparation, and capacity for quantitative analysis.

Ochratoxin A in Slaughtered Pigs and Pork Products

Ochratoxin A (OTA) is a mycotoxin that is produced after the growth of several Aspergillus and Penicillium spp. in feeds or foods. OTA has been proved to possess nephrotoxic, hepatotoxic, teratogenic, neurotoxic, genotoxic, carcinogenic and immunotoxic effects in animals and humans. OTA has been classified as possibly carcinogenic to humans (Group 2B) by the IARC in 2016. OTA can be mainly found in animals as a result of indirect transmission from naturally contaminated feed. OTA found in feed can also contaminate pigs and produced pork products. Additionally, the presence of OTA in pork meat products could be derived from the direct growth of OTA-producing fungi or the addition of contaminated materials such as contaminated spices. Studies accomplished in various countries have revealed that pork meat and pork meat products are important sources of chronic dietary exposure to OTA in humans. Various levels of OTA have been found in pork meat from slaughtered pigs in many countries, while OTA levels were particularly high in the blood serum and kidneys of pigs. Pork products made from pig blood or organs such as the kidney or liver have been often found to becontaminated with OTA. The European Union (EU) has established maximum levels (ML) for OTA in a variety of foods since 2006, but not for meat or pork products. However, the establishement of an ML for OTA in pork meat and meat by-products is necessary to protect human health.

The Antagonistic Effect of Glutamine on Zearalenone-Induced Apoptosis via PI3K/Akt Signaling Pathway in IPEC-J2 Cells

Zearalenone (ZEN) is a non-steroidal estrogen mycotoxin produced by Fusarium fungi, which inevitably exists in human and animal food or feed. Previous studies indicated that apoptosis seems to be a key determinant of ZEN-induced toxicity. This experiment aimed to investigate the protective effects of Glutamine (Gln) on ZEN-induced cytotoxicity in IPEC-J2 cells. The experimental results showed that Gln was able to alleviate the decline of cell viability and reduce the production of reactive oxygen species and calcium (Ca²⁺) induced by ZEN. Meanwhile, the mRNA expression of antioxidant enzymes such as glutathione reductase, glutathione peroxidase, and catalase was up-regulated after Gln addition. Subsequently, Gln supplementation resulted in the nuclear fission and Bad-fluorescence distribution of apoptotic cells were weakened, and the mRNA expression and protein expression of pro-apoptotic genes and apoptotic rates were significantly reduced. Moreover, ZEN reduced the phosphorylation Akt, decreased the expression of Bcl-2, and increased the expression of Bax. Gln alleviated the above changes induced by ZEN and the antagonistic effects of Gln were disturbed by PI3K inhibitor (LY294002). To conclude, this study revealed that Gln exhibited significant protective effects on ZEN-induced apoptosis, and this effect may be attributed to the PI3K/Akt signaling pathway.

Isoflavones in Animals: Metabolism and Effects in Livestock and Occurrence in Feed

Soybeans are a common ingredient of animal feed. They contain isoflavones, which are known to act as phytoestrogens in animals. Isoflavones were described to have beneficial effects on farm animals. However, there are also reports of negative outcomes after the consumption of isoflavones. This review summarizes the current knowledge of metabolization of isoflavones (including the influence of the microbiome, phase I and phase II metabolism), as well as the distribution of isoflavones and their metabolites in tissues. Furthermore, published studies on effects of isoflavones in livestock species (pigs, poultry, ruminants, fish) are reviewed. Moreover, published studies on occurrence of isoflavones in feed materials and co-occurrence with zearalenone are presented and are supplemented with our own survey data.

Adsorbents Reduce Aflatoxin M1 Residue in Milk of Healthy Dairy Cow Exposed to Moderate Level Aflatoxin B1 in Diet and Its Exposure Risk for Humans

This study investigated the effect of moderate risk level (8 µg/kg) AFB₁ in diet supplemented with or without adsorbents on lactation performance, serum parameters, milk AFM₁ content of healthy lactating cows and the AFM₁ residue exposure risk in different human age groups. Forty late healthy lactating Holstein cows (270 ± 22 d in milk; daily milk yield 21 ± 3.1 kg/d) were randomly assigned to four treatments: control diet without AFB₁ and adsorbents (CON), CON with 8 μg/kg AFB₁ (dry matter basis, AF), AF + 15 g/d adsorbent 1 (AD1), AF + 15 g/d adsorbent 2 (AD2). The experiment lasted for 19 days, including an AFB₁-challenge phase (day 1 to 14) and an AFB₁-withdraw phase (day 15 to 19). Results showed that both AFB₁ and adsorbents treatments had no significant effects on the DMI, milk yield, 3.5% FCM yield, milk components and serum parameters. Compared with the AF, AD1 and AD2 had significantly lower milk AFM₁ concentrations (93 ng/L vs. 46 ng/L vs. 51 ng/L) and transfer rates of dietary AFB₁ into milk AFM₁ (1.16% vs. 0.57% vs. 0.63%) (p < 0.05). Children aged 2–4 years old had the highest exposure risk to AFM₁ in milk in AF, with an EDI of 1.02 ng/kg bw/day and a HI of 5.11 (HI > 1 indicates a potential risk for liver cancer). Both AD1 and AD2 had obviously reductions in EDI and HI for all population groups, whereas, the EDI (≥0.25 ng/kg bw/day) and HI (≥1.23) of children aged 2–11 years old were still higher than the suggested tolerable daily intake (TDI) of 0.20 ng/kg bw/day and 1.00 (HI). In conclusion, moderate risk level AFB₁ in the diet of healthy lactating cows could cause a public health hazard and adding adsorbents in the dairy diet is an effective measure to remit AFM₁ residue in milk and its exposure risk for humans.

Occurrence and concentration of mycotoxins in maize dried distillers’ grains produced in Brazil

The presence of mycotoxins in dried distillers’ grains with solubles (DDGS), a by-product of bioethanol production from maize, has been a matter of concern due to the increasing global utilisation of this ingredient in animal feed. In this study, 186 samples of maize DDGS produced in Brazil were analysed for the presence of major mycotoxins: aflatoxins (B1, B2, G1, and G2), fumonisins (B1 and B2), zearalenone (ZEN), deoxynivalenol (DON) and ochratoxin A (OTA). Samples were provided by the local industry between January 2017 and October 2020, and mycotoxins were quantified by LC-MS/MS. More than 98% of the analysed samples were contaminated with mycotoxins, from which 59.9% had a single mycotoxin, 29.9% two mycotoxins, and 9.1% more than two mycotoxins. The most prevalent metabolites were fumonisin B1 and B2, being detected in 98.8% (mean 3,207 μg/kg) and 97.6% (mean 1,243 μg/kg) of the samples, respectively; aflatoxin B1 had the third highest positivity, with 32.3% (mean 1.47 μg/kg), followed by ZEN, with 18.01% (mean 18.2 μg/kg), DON, with 12.9% (mean 59.6 μg/kg), and OTA was not detected. Co-occurrence of total aflatoxins (AFT = aflatoxin B1+B2+G1+G2) and total fumonisins (FBT = fumonisin B1+B2) was observed in 32.07% of the samples analysed for these mycotoxins. Co-occurrence of AFT and ZEN was found in 7.84% of the samples analysed for such mycotoxins, while FBT and DON co-occurred at 13.01%. AFT, FBT, DON and ZEN co-occurred in only one sample (0.84%). Except for FBT, a considerable number of samples presented the evaluated mycotoxins below their respective limit of quantification (LOQ) with percentages of 67.61% for AFT, 81.99% for ZEN, 87.07% for DON and 100% for OTA. Since the production of bioethanol and its by-products is growing worldwide, including in Brazil, mycotoxicological monitoring of maize DDGS is crucial to identify the effects of mycotoxins occurrence in animal feed formulated with this ingredient.

Occurrence of Ochratoxin A in Different Types of Cheese Offered for Sale in Italy

The detection of Ochratoxin A (OTA) in the milk of ruminants occurs infrequently and at low levels, but its occurrence may be higher in dairy products such as cheese. The aim of this study was to investigate the presence of OTA in cheeses purchased in the metropolitan city of Bologna (Italy) and the surrounding area. For the analysis, a LC-MS/MS method with a limit of quantification (LOQ) of 1 µg/kg was used. OTA was detected in seven out of 51 samples of grated hard cheese (concentration range 1.3-22.4 µg/kg), while it was not found in the 33 cheeses of other types which were also analysed. These data show a low risk of OTA contamination for almost all types of cheese analysed. To improve the safety of cheese marketed in grated form, more regulations on cheese rind, which is the part most susceptible to OTA-producing moulds, should be implemented or, alternatively, producers should consider not using the rind as row material for grated cheese. It would be interesting to continue these investigations particularly on grated hard cheeses to have more data to update the risk assessment of OTA in cheese, as also suggested by EFSA in its 2020 scientific opinion on OTA.

Zearalenone Adsorbent Based on a Lyophilized Indigenous Bacterial Lactobacillus plantarum Strain as Feed Additive for Pigs: A Preliminary Study In Vivo

Feed contamination with naturally occurring mycotoxins is an unavoidable condition of significant concern in intensive productions. The presence of high concentrations of zearalenone >1 ppm in the diet can cause major reproductive disorders, particularly in swine. In order to reduce the consequences of intoxication, mycotoxin adsorbents are incorporated into feed. In the present study, zearalenone adsorption capacity of a lyophilized indigenous strain of Lactobacillus plantarum (L4; previously isolated from pig's rectal swabs) was first evaluated in vitro. A preliminary study in vivo was then performed in which the indigenous Lactobacillus plantarum strain was lyophilized and the powder obtained (L-L4) was incorporated into the diet of gilts two gilts received basal diet (control) and two received basal diet containing 2 g/kg L-L4 (treated). After an adaptation period, all the feed was contaminated with zearalenone at a dose of 0.93 mg ZEA/kg. Results from in vitro assay showed that L-L4 adsorbed 87.9% (SD 3.97) of zearalenone in 0.9% NaCl solution. In the in vivo exploratory study, higher daily weight gain and lower vulva area were observed in gilts that incorporated L-L4 to the diet. Additionally, higher zearalenone concentrations were eliminated in faeces from treated animals. The use of a product based on a lyophilized indigenous Lactobacillus strain to protect gilts from detrimental effects of zearalenone consumption has shown promising results so far. However, further studies are required in order to accurately assess its impact and evaluate doses according to different degrees of mycotoxins contamination.

The Effectiveness of Dietary Byproduct Antioxidants on Induced CYP Genes Expression and Histological Alteration in Piglets Liver and Kidney Fed with Aflatoxin B1 and Ochratoxin A

The purpose of this study was to investigate the potential of a byproduct mixture derived from grapeseed and sea buckthorn oil industry to mitigate the harmful damage produced by ochratoxin A and aflatoxin B1 at hepatic and renal level in piglets after weaning. Forty cross-bred TOPIGS-40 hybrid piglets after weaning were assigned to three experimental groups (E1, E2, E3) and one control group (C), and fed with experimental diets for 30 days. The basal diet was served as a control and contained normal compound feed for starter piglets without mycotoxins. The experimental groups were fed as follows: E1-basal diet plus a mixture (1:1) of two byproducts (grapeseed and sea buckthorn meal); E2-the basal diet experimentally contaminated with mycotoxins (479 ppb OTA and 62ppb AFB1); and E3-basal diet containing 5% of the mixture (1:1) of grapeseed and sea buckthorn meal and contaminated with the mix of OTA and AFB1. After 4 weeks, the animals were slaughtered, and tissue samples were taken from liver and kidney in order to perform gene expression and histological analysis. The gene expression analysis showed that when weaned piglets were fed with contaminated diet, the expression of most analyzed genes was downregulated. Among the CYP450 family, CYP1A2 was the gene with the highest downregulation. According to these results, in liver, we found that mycotoxins induced histomorphological alterations in liver and kidney and had an effect on the expression level of CYP1A2, CYP2A19, CYP2E1, and CYP3A29, but we did not detect important changes in the expression level of CY4A24, MRP2 and GSTA1 genes.

Biodiversity of Aflatoxigenic Aspergillus Species in Dairy Feeds in Bulawayo, Zimbabwe

The presence of molds, especially certain species of Aspergillus, in food commodities may contribute to aflatoxin contamination. The aim of this study was to determine the biodiversity of Aspergillus species in dairy feeds from farms in select locations in Zimbabwe and assess their aflatoxin production potential using a polyphasic approach. A total of 96 feed samples were collected, which consisted of dairy feed concentrate, mixed ration, brewers’ spent grain, and grass from 13 farms during the dry season (August–October, 2016) and the following rainy season (January–March, 2017). A total of 199 presumptive isolates representing four sections from genus Aspergillus (Nigri, Fumigati, Flavi, and Circumdati) were recovered from the feeds. Section Flavi, which includes several aflatoxin producers, constituted 23% (n = 46) of the isolates. Species from this section were A. flavus, A. nomius, A. oryzae, A. parasiticus, and A. parvisclerotigenus, and 39 (84.4%) of these showed evidence of aflatoxin production in plate assays. Of the 46 section Flavi isolates examined, some lacked one or more of the five targeted aflatoxin cluster genes (aflD, aflR, aflS, aflM, and aflP). The presence of the five genes was as follows: aflD (76.9%), aflR (48.7%), aflS (74.4%), aflM (64.1%), and aflP (79.5%). This study highlights the species diversity of aflatoxigenic fungi that have the potential to contaminate different types of feed for dairy cows. Our findings underscore the importance of preventing contamination of feedstuffs by these fungi so that aflatoxins do not end up in the diets of consumers.

Proteomics-Based Data Integration of Wheat Cultivars Facing Fusarium graminearum Strains Revealed a Core-Responsive Pattern Controlling Fusarium Head Blight

Fusarium head blight (FHB), mainly occurring upon Fusarium graminearum infection in a wide variety of small-grain cereals, is supposed to be controlled by a range of processes diverted by the fungal pathogen, the so-called susceptibility factors. As a mean to provide relevant information about the molecular events involved in FHB susceptibility in bread wheat, we studied an extensive proteome of more than 7,900 identified wheat proteins in three cultivars of contrasting susceptibilities during their interaction with three F. graminearum strains of different aggressiveness. No cultivar-specific proteins discriminated the three wheat genotypes, demonstrating the establishment of a core proteome regardless of unequivocal FHB susceptibility differences. Quantitative protein analysis revealed that most of the FHB-induced molecular adjustments were shared by wheat cultivars and occurred independently of the F. graminearum strain aggressiveness. Although subtle abundance changes evidenced genotype-dependent responses to FHB, cultivar distinction was found to be mainly due to basal abundance differences, especially regarding the chloroplast functions. Integrating these data with previous proteome mapping of the three F. graminearum strains facing the three same wheat cultivars, we demonstrated strong correlations between the wheat protein abundance changes and the adjustments of fungal proteins supposed to interfere with host molecular functions. Together, these results provide a resourceful dataset that expands our understanding of the specific molecular events taking place during the wheat-F. graminearum interaction.

Mycotoxin Determination in Animal Feed: An LC-FLD Method for Simultaneous Quantification of Aflatoxins, Ochratoxins and Zearelanone in This Matrix

Mycotoxins are toxic compounds for humans and animals that are produced by fungi. Mycotoxin contamination in feed is a global safety concern and effective control of these compounds in this matrix is needed. This study proposes a simple, cost-effective analytical method based on liquid chromatography coupled with a fluorescence detector, which is suitable for the routine monitoring of some of the most important mycotoxins in feed: aflatoxins (G2, G1, B2, and B1), zearalenone, and ochratoxins A and B. Mycotoxin extraction, chromatographic separation and quantification are carried out simultaneously for all mycotoxins. The extraction procedure is performed using acetonitrile, water and orthophosphoric acid (80:19:1). Purification of the extract is carried out using an OASIS PRIME HLB solid-phase extraction cartridge followed by a dispersive liquid–liquid microextraction procedure. Aflatoxins G1 and B1 are derivatized post-column (photochemical reactor at 254 nm) to increase their signal. The method has been validated in feed for pigs, cows, sheep, and poultry with very satisfactory results. The detection limits are 2 μg/kg for aflatoxins B1 and G1, 0.64 μg/kg for aflatoxins B2 and G2, 42 μg/kg for zearalenone, and 5 μg/kg for ochratoxins A and B. These values are low enough to allow for monitoring of these mycotoxins in feed. Global recovery values were between 73.6% and 88.0% for all toxins with a relative standard deviation (RSD) % < 7%. This methodology will facilitate laboratory control and analysis of mycotoxins in feed.

Assessment of Fungal Contamination in Fish Feed from the Lake Victoria Basin, Uganda

The emergence of commercial fish farming has stimulated the establishment of fish feed factories in Uganda. However, no information is available on the safety of the feed, mainly due to lack of mycotoxin testing facilities and weak regulatory systems. A study was carried out to examine fungal colonization and mycotoxin contamination in fish feed samples (n = 147) of different types collected from nine fish farms (n = 81) and seven fish feed factories (n = 66) in the Lake Victoria Basin (LVB). Fungi were isolated in potato dextrose agar, grouped into morphotypes and representative isolates from each morphotype were identified based on the internal transcribed spacer (ITS) region of ribosomal DNA sequences. Aflatoxin B₁ (AFB₁) and total fumonisin (combinations of B₁, B₂ and B₃; hereinafter named fumonisin) levels in feed samples were determined by enzyme-linked immunosorbent assay (ELISA). A wide range of fungi, including toxigenic Aspergillus flavus and Fusarium verticillioides, were isolated from the fish feed samples. AFB₁ was detected in 48% of the factory samples and in 63% of the farm samples, with toxin levels <40 and >400 µg/kg, respectively. Similarly, 31% of the factory samples and 29% of the farm samples had fumonisin contamination ranging between 0.1 and 4.06 mg/kg. Pellets and powder had higher mycotoxin contamination compared to other commercially available fish feed types. This study shows AFB₁ as a potential fish feed safety issue in the LVB and suggests a need for more research on mycotoxin residues in fish fillets.

Potential adverse effects on animal health and performance caused by the addition of mineral adsorbents to feeds to reduce mycotoxin exposure

The contamination of feed with mycotoxins is a continuing feed quality and safety issue, leading to significant losses in livestock production and potential human health risks. Consequently, various methods have been developed to reduce the occurrence of mycotoxins in feed; however, feed supplementation with clay minerals or mineral adsorbents is the most prominent approach widely practiced by farmers and the feed industry. Due to a negatively charged and high surface area, pore volume, swelling ability, and high cation exchange capacity, mineral adsorbents including bentonite, zeolite, montmorillonite, and hydrated sodium calcium aluminosilicate can bind or adsorb mycotoxins to their interlayer spaces, external surface, and edges. Several studies have shown these substances to be partly or fully effective in counteracting toxic effects of mycotoxins in farm animals fed contaminated diets and thus are extensively used in livestock production to reduce the risk of mycotoxin exposure. Nevertheless, a considerable number of studies have indicated that these agents may also cause undesirable effects in farm animals. The current work aims to review published reports regarding adverse effects that may arise in farm animals (with a focus on pig and poultry) and potential interaction with veterinary substances and nutrients in feeds, when mineral adsorbents are utilized as a technological feed additive. Furthermore, results of in vitro toxicity studies of both natural and modified mineral adsorbents on different cell lines are reported. Supplementation of mycotoxin-contaminated feed with mineral adsorbents must be carefully considered by farmers and feed industry.

Searching for FHB Resistances in Bread Wheat: Susceptibility at the Crossroad

Fusarium head blight (FHB), primarily caused by Fusarium graminearum, is one of the most devastating fungal wheat diseases. During the past decades, many efforts have been deployed to dissect FHB resistance, investigating both the wheat responses to infection and, more recently, the fungal determinants of pathogenicity. Although no total resistance has been identified so far, they demonstrated that some plant functions and the expression of specific genes are needed to promote FHB. Associated with the increasing list of F. graminearum effectors able to divert plant molecular processes, this fact strongly argues for a functional link between susceptibility-related factors and the fate of this disease in wheat. In this review, we gather more recent data concerning the involvement of plant and fungal genes and the functions and mechanisms in the development of FHB susceptibility, and we discuss the possibility to use them to diversify the current sources of FHB resistance.

Excess dietary tryptophan mitigates aflatoxicosis in growing quails

A biological assay was carried out to evaluate the impact of dietary tryptophan (TRP) in aflatoxin B₁ -contaminated diets (AFB₁ -D) on performance, blood parameters, immunity, meat quality and microbial populations of intestine in Japanese quails. Six experimental diets were formulated to include two levels of dietary TRP; 2.9 (moderate high: MH-TRP) and 4.9 g/kg (excess: Ex-TRP); and three levels of AFB₁ (0.0, 2.5, and 5.0 mg/kg). Each experimental diet was fed to the one of the six groups of birds from 7 to 35 days of age in a completely randomized design with 2 × 3 factorial arrangement. Decrease in feed intake, body weight gain and gain:feed in birds fed 5.0 mg/kg AFB₁ -D was restored to the control level by 4.9 g TRP/kg of the diet. The hepatic enzymes in blood were elevated in quails fed on AFB₁ -D but attenuated by 4.9 g TRP/kg of the diet (Ex-TRP; p ≤ .01). High serum uric acid in birds challenged with AFB₁ significantly decreased by Ex-TRP (p ≤ .01). The skin thickness to 2,4-dinitro-1-chlorobenzene challenge suppressed by AFB₁ but increased by Ex-TRP diet (p ≤ .02). The AFB₁ increased the malondialdehyde in meat, whereas TRP efficiently diminished malondialdehyde production (p ≤ .01). The greatest drip loss and pH in meat were observed in the birds fed 5.0 mg/kg AFB₁ -D but Ex-TRP augmented the adverse effects of AFB₁ (p ≤ .01). The Ex-TRP reduced the total microbial and Escherichia coli counts (p ≤ .01). The adverse effect of AFB₁ on ileal Lactic acid bacteria was completely prevented by Ex-TRP (p ≤ .03). This study showed that tryptophan supplementation could be considered as a powerful nutritional tool to ameliorate the adverse effects of AFB₁ in growing quails.

Occurrence of Mycotoxins in Swine Feeding from Spain

A survey including 228 pig feed samples from Spain has been developed, exploring the occurrence of 19 mycotoxins (aflatoxins B1, B2, G1 and G2, ochratoxin A, fumonisins B1 and B2, citrinin, zearalenone, deoxynivalenol, fusarenon X, sterigmatocystin, T-2 toxin, HT-2 toxin, enniatins A, A1, B and B2, and beauvericin). The samples were analysed by solid-liquid extraction followed by liquid chromatography coupled with fluorescence or mass spectrometry detection. Enniatin B was found in 100% of the samples (up to 1200 µg/kg) and beauvericin in more than 90%. Moreover, 40% of samples were contaminated with more than five mycotoxins. This high occurrence is insurmountable and surpasses all previous studies, probably due to the inclusion of emerging mycotoxins, scarcely explored. The majority of the samples (96.9%) were in accordance with EU regulations, which do not address emerging mycotoxins or co-occurrence. These results show that in order to ensure mycotoxin absence, emerging mycotoxins should always be considered.

Prevalent Mycotoxins in Animal Feed: Occurrence and Analytical Methods

Today, we have been witnessing a steady tendency in the increase of global demand for maize, wheat, soybeans, and their products due to the steady growth and strengthening of the livestock industry. Thus, animal feed safety has gradually become more important, with mycotoxins representing one of the most significant hazards. Mycotoxins comprise different classes of secondary metabolites of molds. With regard to animal feed, aflatoxins, fumonisins, ochratoxins, trichothecenes, and zearalenone are the more prevalent ones. In this review, several constraints posed by these contaminants at economical and commercial levels will be discussed, along with the legislation established in the European Union to restrict mycotoxins levels in animal feed. In addition, the occurrence of legislated mycotoxins in raw materials and their by-products for the feeds of interest, as well as in the feeds, will be reviewed. Finally, an overview of the different sample pretreatment and detection techniques reported for mycotoxin analysis will be presented, the main weaknesses of current methods will be highlighted.

Efficacy of Bacillus subtilis ANSB060 Biodegradation Product for the Reduction of the Milk Aflatoxin M₁ Content of Dairy Cows Exposed to Aflatoxin B₁

This study was conducted to determine the effect of Bacillus subtilis ANSB060 biodegradation product (BDP) in reducing the milk aflatoxin M₁ (AFM₁) content of dairy cows fed a diet contaminated with aflatoxin B₁ (AFB₁). Twenty-four Chinese Holstein cows (254 ± 19 d in milk; milk production 19.0 ± 1.2 kg d⁻¹) were assigned to three dietary treatments, as follows: (1) control diet (CON), consisting of a basal total mixed ration (TMR); (2) aflatoxin diet (AF), containing CON plus 63 μg of AFB₁ kg⁻¹ of diet dry matter; and (3) aflatoxin diet plus BDP (AF + BDP), containing AF plus BDP at 0.2% of diet dry matter. The experiment lasted 12 days, including an AFB₁-dosing period from days one to eight, followed by a clearance period from days nine to twelve. Milk samples were collected on days 2, 4, 6, and 8–12, and the plasma was sampled on day 9, before morning feeding. Short-term AFB₁ exposure did not affect the milk production and composition. The plasma biochemical indices, except for lactic dehydrogenase (LDH), were also not changed by the AFB₁ intake. The plasma LDH level was significantly elevated (p < 0.05) following dietary treatment with AFB₁, while no significant difference was observed between the AF + BDP and CON treatments. Adding BDP to the AFB₁-contaminaed diet resulted in a significant reduction in AFM₁ concentration (483 vs. 665 ng L⁻¹) in the milk, AFM₁ excretion (9.14 vs. 12.71 μg d⁻¹), and transfer rate of dietary AFB₁ to milk AFM₁ (0.76 vs. 1.06%). In conclusion, the addition of BDP could be an alternative method for reducing the dietary AFB₁ bioavailability in dairy cows.

Fusarium Species and Mycotoxins Contaminating Veterinary Diets for Dogs and Cats

Veterinary diets are intended for diseased animals and may contain cereal grains, mainly maize and/or wheat. These, in turn, are often infected with pathogens of the Fusarium genus, which are able to produce numerous harmful mycotoxins. Forty-two samples of veterinary diets for dogs and cats were analyzed for the presence of Fusarium species and mycotoxins. Species were identified using molecular methods and the ergosterol and mycotoxins (fumonisin B₁, deoxynivalenol, nivalenol and zearalenone) were quantified using HPLC methods. Two Fusarium species were identified: Fusarium proliferatum and Fusarium verticillioides. The highest concentrations of fumonisin B₁, deoxynivalenol, nivalenol and zearalenone were 74.83, 2318.05, 190.90, and 45.84 ng/g, respectively. Only 9.5% of the samples were free from Fusarium mycotoxins. The acceptable limits of mycotoxin content in animal feed, specified by the EU regulations, were not exceeded in any of the samples tested. The mean mycotoxin content in veterinary diets for cats was lower than for dogs. Thus, it is recommended that veterinary diets are examined, since the mycotoxin contamination pose additional risk to animal health. The knowledge on Fusarium occurrence in veterinary diets is scarce and as far as we are aware this is the first report concerning the occurrence of Fusarium spp. and their important secondary metabolites—mycotoxins—in different types of veterinary diets for companion animals in Poland.

Bacillus licheniformis CK1 alleviates the toxic effects of zearalenone in feed on weaned female Tibetan piglets

Zearalenone (ZEA) is widely present in feedstuffs and raw materials, causing reproductive disorders in animals. In this study, Bacillus licheniformis CK1 was used to detoxify ZEA in feed for alleviating its effect in Tibetan piglets. A total of 18 weaned female Tibetan piglets were randomly divided into 3 groups: control group (Control, ZEA-free basal diet); treatment group 1 (T1, ZEA-contaminated diet); and treatment group 2 (T2, ZEA-contaminated but pre-fermented by CK1 diet). There were no significant differences of average daily feed intake (ADFI), average daily gain (ADG), and feed efficiency (FE) among the 3 groups (P > 0.05). The T1 treatment significantly increased the vulva size and relative weight of the reproductive organ (P < 0.05), compared with the Control. However, the T2 treatment caused a significant reduction (P < 0.05) in vulva size and relative weight of the reproductive organ compared with the T1 group. The levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), progesterone (P), and estradiol (E2) in the T1 group were significantly lower (P < 0.05) than those in the Control, while the levels of LH, P, and E2 in the T2 group were significantly greater (P < 0.05) than those in the T1 group. Zearalenone significantly increased (P < 0.05) the expression of estrogen receptor α in uterus and ovary and estrogen receptor β in vagina, while these indicators were not significant different (P > 0.05) between the T2 group and the Control group. In comparison with the Control group, ZEA significantly increased (P < 0.05) expression of several ATP-binding cassette (ABC) transporters: ABCB1 and ABCb4 in the vagina, ABCA1 and ABCb4 in the uterus, and ABCB1, ABCb4, ABCD3, and ABCG2 in the ovary, while these transporters in the T2 group were significantly decreased (P < 0.05) compared with the T1 group. In conclusion, the present study demonstrates that B. licheniformis CK1 could alleviate the harmful effect of ZEA in Tibetan piglets.

The Protective Role of Bacillus velezensis A2 on the Biochemical and Hepatic Toxicity of Zearalenone in Mice

Zearalenone (ZEN) is an estrogen-like mycotoxin produced by Fusarium that seriously compromises the safety of animal and human health. In this study, our aim was to evaluate the protective effect of Bacillus velezensis A2 against biochemical and pathological changes induced by zearalenone in mice. Kunming mice (n = 40; 25 ± 2 g) were allotted to four treatment groups: a control group (basic feed); a ZEN group (basic feed with a ZEN dose of 60 mg/kg); an A2 strain fermented feed group (150 g of feed mixed with 150 mL of sterile distilled water and inoculated with 5 mL of phosphate buffer salt (PBS) resuspended A2 strain); and an A2 strain fermented ZEN-contaminated feed group. (A2 strain group 150 mL pure bacterial distilled water system mixed with 150 g ZEN-contaminated feed.) Our results showed that the Bacillus velezensis A2 strain can completely degrade the ZEN-contaminated feed within 5 days. (The concentration of ZEN in fermentation was 60 μg/mL.) After the mice fed for 28 days, compared with the control group, the activities of AST and ALT were increased, the activities of glutathione peroxidase (GSH-PX) and total superoxide dismutase (T-SOD) were decreased, and the amount of creatinine (CRE), blood urea nitrogen (BUN), uric acid (UA), and malondialdehyde (MDA) in the ZEN group were increased in the mice serum (p < 0.05; p < 0.01). However, compared with the ZEN group, these biochemical levels were reversed in the A2 strain fermented feed group and in the A2 strain fermented ZEN-contaminated feed group (p < 0.05; p < 0.01). Furthermore, histopathological analysis only showed pathological changes of the mice liver in the ZEN group. The results showed that Bacillus velezensis A2 as additive could effectively remove ZEN contamination in the feed and protect the mice against the toxic damage of ZEN. In conclusion, Bacillus velezensis A2 has great potential use as a microbial feed additive to detoxify the toxicity of zearalenone in production practice.

Levels of zearalenone and its metabolites in sun-dried kapenta fish and water of Lake Kariba in Zambia - A preliminary study

Contamination of food with mycotoxins and the associated possibilities of human intoxication is a serious problem in Africa. One of the most widespread mycotoxins is zearalenone (ZEN), which usually occurs in food of vegetable origin. On the other hand, information about ZEN in products of animal origin in African countries is extremely scanty. During the present study, levels of ZEN and its analogs: α-zearalenol (α-ZEL) and β-zearalenol (β-ZEL) were measured by high performance liquid chromatography (HPLC) with fluorescence detection in sun-dried kapenta fish - traditional Zambian food, as well as in the water of Lake Kariba - the main source of kapenta fish in Zambia. This study revealed that levels of ZEN in sun-dried kapenta fish fluctuated from 27.2 μg·kg^-1 to 53.9 μg·kg^-1, whereas the contamination of water from Lake Kariba with ZEN is rather minimally similar to the content of ZEN analogs in both kapenta fish and water. The obtained results have shown that sun-dried kapenta fish of Lake Kariba contain ZEN and may contribute to the exposure of consumers to this substance.

Advances in Biodetoxification of Ochratoxin A-A Review of the Past Five Decades

Ochratoxin A (OTA) is a toxic secondary fungal metabolite that widely takes place in various kinds of foodstuffs and feeds. Human beings and animals are inevitably threatened by OTA as a result. Therefore, it is necessary to adopt various measures to detoxify OTA-contaminated foods and feeds. Biological detoxification methods, with better safety, flavor, nutritional quality, organoleptic properties, availability, and cost-effectiveness, are more promising than physical and chemical detoxification methods. The state-of-the-art research advances of OTA biodetoxification by degradation, adsorption, or enzymes are reviewed in the present paper. Researchers have discovered a good deal of microorganisms that could degrade and/or adsorb OTA, including actinobacteria, bacteria, filamentous fungi, and yeast. The degradation of OTA to non-toxic or less toxic OTα via the hydrolysis of the amide bond is the most important OTA biodegradation mechanism. The most important influence factor of OTA adsorption capacity of microorganisms is cell wall components. A large number of microorganisms with good OTA degradation and/or adsorption ability, as well as some OTA degradation enzymes isolated or cloned from microorganisms and animal pancreas, have great application prospects in food and feed industries.

Effects of zearalenone on the localization and expression of the growth hormone receptor gene in the uteri of post-weaning piglets

OBJECTIVE

In this study, we investigated the adverse effects of dietary zearalenone (ZEA) (0.5 to 1.5 mg/kg diet) on the localization and expression of the growth hormone receptor (GHR) in the uteri of post-weaning gilts and explored alternative mechanism of the reproductive toxicity of ZEA on piglets.

METHODS

A total of forty healthy piglets (Duroc×Landrace×Large White) aged 28 d were selected for study. Piglets were transferred to single cages after 10 days' adaptation on an obstetric table. The animals were allocated to one of four treatments: a normal basal diet supplemented with 0 (Control), 0.5 (ZEA0.5), 1.0 (ZEA1.0), or 1.5 (ZEA1.5) mg/kg purified ZEA, and fed for 35 d after the 10-d adaptation. Analyzed ZEA concentrations in the diets were 0, 0.52±0.07, 1.04±0.03, and 1.51±0.13 mg/kg, respectively. At the end of the feeding trial, piglets were euthanized after being fasted for 12 h. Two samples of uterine tissue from each pig were rapidly collected, one of which was stored at -80°C for analysis of the relative mRNA and protein expression of GHR, and the second was promptly fixed in Bouin's solution for immunohistochemical analysis.

RESULTS

The relative weight of the uteri and thickness of the myometrium and endometrium increased linearly (p<0.001) and quadratically (p<0.001) with an increasing level of ZEA. The results of immunohistochemical analysis indicated that GHR immunoreactive substance was mainly localizated in the cytoplasm of uterine smooth muscle, glandular epithelial, luminal epithelial, stromal, and vascular endothelial cells. In contrast, nuclear staining was rarely observed. The immunoreactive integrated optic density of GHR in the myometrium, luminal epithelium, glandular epithelium, and whole uteri of weaning gilts increased linearly (p<0.001) and quadratically (p<0.05) with an increasing level of ZEA. The mRNA and protein expression of GHR in the uteri of weaning gilts increased linearly (p<0.001) and quadratically (p<0.05) with an increasing level of ZEA.

CONCLUSION

In conclusion, ZEA at a concentration of 0.5 mg/kg was sufficient to significantly thicken the myometrium and endometrium, and at a concentration of 1.0 mg/kg induced a high level of GHR expression to promote growth and development of the uteri. This revealed an alternative molecular mechanism whereby ZEA induces growth and development of the uteri and provides a theoretical basis for the revision of Chinese feed hygiene standards.

Screening of Deoxynivalenol Producing Strains and Elucidation of Possible Toxigenic Molecular Mechanism

In this study, seven strains of Fusarium graminearum were isolated from wheat, of which six were identified to produce deoxynivalenol and the production of deoxynivalenol was assessed. F. graminearum strain Fg1 was noted to produce 1.0 μg/g deoxynivalenol during the incubation period in the Czapek yeast broth, while none was detected in F. graminearum strain Fg2. Hence, the differences in proteomes and transcriptomes of Fg1 and Fg2 were compared to analyze the mechanism underlying deoxynivalenol production. Among the 66 significantly differentially expressed proteins in Fg1, 39 and 27 were more or less abundant expressed. Functional analysis suggested that the enzymes involved in the methylerythritol 4-phosphate and mevalonate pathways, which provide a substrate for biosynthesis of farnesyl pyrophosphate, a precursor of DON, were activated in Fg1. The transcriptomics data demonstrated that the expression level of a majority of genes, including trichothecene biosynthetic genes, protein kinases, and transcription factors, involved in trichothecene biosynthesis was higher in Fg1 than in Fg2. The results also revealed differential expression profiles of deoxynivalenol biosynthesis genes in strains Fg1 and Fg2, which emphasized their deoxynivalenol producing ability and the underlying mechanism.

Development and inter-laboratory study of a method for quantifying ochratoxin A in pet foods

An analytical method for quantifying ochratoxin A (OTA) in pet foods using high-performance liquid chromatography was developed, and an inter-laboratory study was conducted. OTA was extracted from samples with aqueous acetonitrile. The extract was purified by an immunoaffinity column, OCHRAKING, and analysed by high performance liquid chromatography with fluorescence detection. The limits of quantification by this method were 2 µg/kg for dry and semidry pet food and 1 µg/kg for wet type pet food. The calibration curve showed linearity in the range of 0.5-50 ng/ml (equivalent to 1-100 µg/kg for wet type pet food). The mean recoveries of OTA spiked at 1-5 µg/kg were in the range of 83.0-106% and relative standard deviations of the in-house method validation were 2.6-6.8%. The mean recoveries, repeatability, reproducibility and the Horwitz ratios for OTA from the inter-laboratory validation study were 75.6-83.1%, 3.5-6.1%, 5.0-15.0% and 0.23-0.68, respectively.

The Role of Biofuels Coproducts in Feeding the World Sustainably

One of the grand challenges facing our society today is finding solutions for feeding the world sustainably. The food-versus-fuel debate is a controversy embedded in this challenge, involving the trade-offs of using grains and oilseeds for biofuels production versus animal feed and human food. However, only 6% of total global grain produced is used to produce ethanol. Furthermore, biofuels coproducts contribute to sustainability of food production because only 1% to 2.5% of the overall energy efficiency is lost from converting crops into biofuels and animal feed, and approximately one-third of the corn used to produce ethanol is recovered as feed coproducts. Extensive research has been conducted over the past 15 years on biofuels coproducts to (a) optimize their use for improving caloric and nutritional efficiency in animal feeds, (b) identify benefits and limitations of use in various animal diets,

Safe food and feed through an integrated toolbox for mycotoxin management: the MyToolBox approach

There is a pressing need to mobilise the wealth of knowledge from the international mycotoxin research conductedover the past 25-30 years, and to perform cutting-edge research where knowledge gaps still exist. This knowledgeneeds to be integrated into affordable and practical tools for farmers and food processors along the chain inorder to reduce the risk of mycotoxin contamination of crops, feed and food. This is the mission of MyToolBox – a four-year project which has received funding from the European Commission. It mobilises a multi-actorpartnership (academia, farmers, technology small and medium sized enterprises, food industry and policystakeholders) to develop novel interventions aimed at achieving a significant reduction in crop losses due tomycotoxin contamination. Besides a field-to-fork approach, MyToolBox also considers safe use options ofcontaminated batches, such as the efficient production of biofuels. Compared to previous efforts of mycotoxin reduction strategies, the distinguishing feature of MyToolBox is to provide the recommended measures to theend users along the food and feed chain in a web-based MyToolBox platform (e-toolbox). The project focuseson small grain cereals, maize, peanuts and dried figs, applicable to agricultural conditions in the EU and China. Crop losses using existing practices are being compared with crop losses after novel pre-harvest interventionsincluding investigation of genetic resistance to fungal infection, cultural control (e.g. minimum tillage or cropdebris treatment), the use of novel biopesticides suitable for organic farming, competitive biocontrol treatment and development of novel modelling approaches to predict mycotoxin contamination. Research into post-harvestmeasures includes real-time monitoring during storage, innovative sorting of crops using vision-technology, novelmilling technology and studying the effects of baking on mycotoxins at an industrial scale.

Aflatoxin B1, zearalenone and deoxynivalenol in feed ingredients and complete feed from different Province in China

BACKGROUND

The current study was carried out to provide a reference for monitory of aflatoxin B₁ (AFB₁), zearalenone (ZEN) and deoxynivalenol (DON) contamination in feed ingredients and complete feeds were collected from different Province in China from 2013 to 2015.

METHODS

A total of 443 feed ingredients, including 220 corn, 24 wheat, 24 domestic distillers dried grains with soluble (DDGS), 55 bran, 20 wheat shorts and red dog, 37 imported DDGS, 34 corn germ meal and 29 soybean meal as well as 127 complete feeds including 25 pig complete feed (powder), 90 pig complete feed (pellet), six duck complete feed and six cattle complete feed were randomly collected from different Province in China, respectively, by high-performance chromatography in combined with UV or fluorescence analysis.

RESULTS

The incidence rates of AFB₁, ZEN and DON contamination of feed ingredients and complete feeds were 80.8, 92.3 and 93.9 %, respectively. The percentage of positive samples for DON ranged from 66.7 to 100 %. Domestic DDGS and imported DDGS presented the most serious contamination AFB₁, ZEN and DON contamination levels of feeds ranged from 61.5 to 100 %, indicated that serious contamination over the studied 3-year period.

CONCLUSION

The current data provide clear evidence that AFB₁, ZEN and DON contamination of feed ingredients and complete feeds in different Province in China is serious and differs over past 3-year. The use of corn, domestic DDGS, imported DDGS and corn germ meal, which may be contaminated with these three mycotoxins, as animal feed may triggered a health risk for animal. Feeds are most contaminated with DON followed by ZEN and AFB₁. Mycotoxins contamination in feed ingredients and complete feeds should be monitored routinely in China.