Effects of feeding blends of grains naturally contaminated with Fusarium mycotoxins on production and metabolism in broilers

Effect of deoxynivalenol on inflammatory injury on the glandular stomach in chick embryos

Deoxynivalenol (DON) has a strong toxic effect on the gastrointestinal mucosa of poultry. In this study, we evaluated chicken embryo development and glandular stomach damage to clarify the immunotoxic effects of DON injected through the allantoic cavity of chicken embryos. The glandular stomach index, routine blood indices, plasma inflammatory factors, pathological changes in the glandular stomach, and transcriptome results were analyzed in the hatching chicks. The results showed that DON was supertoxic to chicken embryos, causing edema, shedding, and bleeding of the mucosa of the glandular stomach, which triggered inflammatory reactions. As the toxin concentration increased, the immune system was successively activated and inhibited, and regulation was carried out by the differential regulation of the mitogen-activated protein kinase (MAPK) signal pathway. These results suggested that the immunotoxic effect of DON on the glandular stomach of chicken embryos was closely related to the regulation of the MAPK signaling pathway.

Effects of Aflatoxins and Fumonisins, Alone or in Combination, on Performance, Health, and Safety of Food Products of Broiler Chickens, and Mitigation Efficacy of Bentonite and Fumonisin Esterase

The current study evaluated the effects of feeding diets contaminated with aflatoxin B1 (AFB1), fumonisins (FBs), or both on the performance and health of broiler chickens and the safety of their food products as well as the efficacy of bentonite and fumonisin esterase to mitigate the effects of these mycotoxins under conditions representative for sub-Saharan Africa (SSA). Four hundred one-day-old Cobb 500 broiler chickens were randomly assigned to 20 treatments with either a control diet, a diet with moderate AFB1 (60 μg/kg feed) or high AFB1 (220 μg/kg feed), or FBs (17,430 μg FB1+FB2/kg feed), alone or in combination, a diet containing AFB1 (either 60 or 220 μg/kg) and/or FBs (17,430 μg FB1+FB2/kg) and bentonite or fumonisin esterase or both, or a diet with bentonite or fumonisin esterase only. The experimental diets were given to the birds from day 1 to day 35 of age, and the effects of the different treatments on production performance were assessed by feed intake (FI), body weight gain (BWG), and feed conversion ratio (FCR). Possible health effects were evaluated through blood biochemistry, organ weights, mortality, liver gross pathological changes, and vaccine response. Residues of aflatoxins (AFB1, B2, G1, G2, M1 and M2) were determined in plasma, muscle, and liver tissues using validated UHPLC-MS/MS methods. The results obtained indicated that broiler chickens fed high AFB1 alone had poor FCR when compared to a diet with both high AFB1 and FBs (p = 0.0063). Serum total protein and albumin from birds fed FBs only or in combination with moderate or high AFB1 or detoxifiers increased when compared to the control (p < 0.05). Liver gross pathological changes were more pronounced in birds fed contaminated diets when compared to birds fed the control or diets supplemented with mycotoxin detoxifiers. The relative weight of the heart was significantly higher in birds fed high AFB1 and FBs when compared to the control or high AFB1 only diets (p < 0.05), indicating interactions between the mycotoxins. Inclusion of bentonite in AFB1-contaminated diets offered a protective effect on the change in weights of the liver, heart and spleen (p < 0.05). Residues of AFB1 were detected above the limit of quantification (max: 0.12 ± 0.03 μg/kg) in liver samples only, from birds fed a diet with high AFB1 only or with FBs or the detoxifiers. Supplementing bentonite into these AFB1-contaminated diets reduced the levels of the liver AFB1 residues by up to 50%. Bentonite or fumonisin esterase, alone, did not affect the performance and health of broiler chickens. Thus, at the doses tested, both detoxifiers were safe and efficient for use as valid means of counteracting the negative effects of AFB1 and FBs as well as transfer of AFB1 to food products (liver) of broiler chickens.

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.

Effects of moldy corn on the performance, antioxidant capacity, immune function, metabolism and residues of mycotoxins in eggs, muscle, and edible viscera of laying hens

Mycotoxins, including aflatoxin B1 (AFB₁), zearalenone (ZEN) and deoxynivalenol (DON), are common contaminants of moldy feeds. Mycotoxins can cause deleterious effects on the health of chickens and can be carried over in poultry food products. This study was conducted to investigate the effects of moldy corn (containing AFB₁, ZEN, and DON) on the performance, health, and mycotoxin residues of laying hens. One hundred and eighty 400-day-old laying hens were divided into 4 treatments: basal diet (Control), basal diet containing 20% moldy corn (MC20), 40% moldy corn (MC40) and 60% moldy corn (MC60). At d 20, 40, and 60, the performance, oxidative stress, immune function, metabolism, and mycotoxin residues in eggs were determined. At d 60, mycotoxin residues in muscle and edible viscera were measured. Results showed the average daily feed intake (ADFI) and laying performance of laying hens were decreased with moldy corn treatments. All the moldy corn treatments also induced significant oxidative stress and immunosuppression, reflected by decreased antioxidase activities, contents of cytokines, immunoglobulins, and increased malonaldehyde level. Moreover, the activities of aspartate aminotransferase and alanine transaminase were increased by moldy corn treatments. The lipid metabolism was influenced in laying hens receiving moldy corn, reflected by lowered levels of total protein, high density lipoprotein cholesterol, low density lipoprotein cholesterol, total cholesterol, and increased total triglyceride as well as uric acid. The above impairments were aggravated with the increase of mycotoxin levels. Furthermore, AFB₁ and ZEN residues were found in eggs, muscle, and edible viscera with moldy corn treatments, but the residues were below the maximum residue limits. In conclusion, moldy corn impaired the performance, antioxidant capacity, immune function, liver function, and metabolism of laying hens at d 20, 40, and 60. Moldy corn also led to AFB₁ residue in eggs at d 20, 40, and 60, and led to both AFB₁ and ZEN residues in eggs at days 40 and 60, and in muscle and edible viscera at d 60. The toxic effects and mycotoxin residues were elevated with the increase of moldy corn levels in feed.

Dietary supplementation with selenium nanoparticles-enriched Lactobacillus casei ATCC 393 alleviates intestinal barrier dysfunction of mice exposed to deoxynivalenol by regulating endoplasmic reticulum stress and gut microbiota

Deoxynivalenol (DON), a secondary product of Fusarium metabolism, is common in wheat, corn, barley and other grain crops, posing a variety of adverse effects to environment, food safety, human and animal health. The absorption of DON mainly occurs in the proximal part of the small intestine, which can induce intestinal mucosal epithelial injury, and ultimately affect the growth performance and production performance of animals. This study was conducted to investigate the protective effects of selenium nanoparticles (SeNPs)-enriched Lactobacillus casei ATCC 393 (L. casei ATCC 393) on intestinal barrier function of C57BL/6 mice exposed to DON and its association with endoplasmic reticulum stress (ERS) and gut microbiota. The results showed that DON exposure increased the levels of interleukin-6 (IL-6) and interleukin-8 (IL-8), decreased the levels of interleukin-10 (IL-10) and transforming growth factor beta (TGF-β), caused a redox imbalance and intestinal barrier dysfunction, decreased the mRNA levels of endoplasmic reticulum- resident selenoproteins, activated ERS-protein kinase R-like endoplasmic reticulum kinase (PERK) signaling pathway, altered the composition of the gut microbiota and decreased short-chain fatty acids (SCFAs) content. Dietary supplementation with SeNPs-enriched L. casei ATCC 393 can effectively protect the integrity of intestinal barrier function by reducing inflammatory response, enhancing the antioxidant capacity, up-regulating the mRNA levels of endoplasmic reticulum-resident selenoproteins, inhibiting the activation of PERK signaling pathway, reversing gut microbiota dysbiosis and increasing the content of SCFAs in mice exposed to DON. In conclusion, dietary supplementation with SeNPs-enriched L. casei ATCC 393 effectively alleviated intestinal barrier dysfunction induced by DON in C57BL/6 mice, which may be closely associated with the regulation of ERS and gut microbiota.

Can Red Yeast (Sporidiobolus pararoseus) Be Used as a Novel Feed Additive for Mycotoxin Binders in Broiler Chickens?

Mycotoxin-contaminated feeds may negatively affect broiler chickens’ health; hence, a sustainable approach to achieve mycotoxin elimination is necessary. This study aimed to evaluate the efficacy of red yeast (Sporidiobolus pararoseus; RY) as a novel mycotoxin binder in broilers. A total of 1440 one-week-old male broiler chicks were randomly assigned to 12 treatments in a 3 × 4 factorial design. The dietary treatments included three levels of mycotoxin-contaminated diets (0 µg kg−1 (0% of mycotoxin; MT), 50 µg kg−1 (50% MT), and 100 µg kg−1 (100% MT)) and four levels of mycotoxin binders (0.0 and 0.5 g kg−1 commercial binder, and 0.5 and 1.0 g kg−1 RY). Experimental diets were contaminated with aflatoxin B1, zearalenone, ochratoxin A, T-2 toxin, and deoxynivalenol in the basal diet. Furthermore, the parameters including feed intake, body weight, and mortality rate were recorded on a weekly basis. After feeding for 28 days, blood and organ samples were collected randomly to determine the blood biochemistry, relative organ weights, and gut health. The results indicated that mycotoxin-contaminated diets reduced the average daily weight gain (ADG), villus height (VH), and villus height per the crypt depth ratio (VH:CD) of the intestine, as well as the population of Lactobacillus sp. and Bifidobacterium sp. in the cecal (p < 0.05), whereas they increased the mycotoxins concentration in the blood samples and the apoptosis cells (TUNEL positive) in the liver tissue (p < 0.01) of broiler chicken. In contrast, RY-supplemented diets had better ADG values and lower chicken mortality rates (p < 0.05). Moreover, these combinations positively impacted the relative organ weights, blood parameters, bacteria population, intestinal morphology, and pathological changes in the hepatocytes (p < 0.05). In conclusion, RY supplementation effectively alleviated the toxicity that is induced by AFB1 and OTA, mainly, and could potentially be applied as a novel feed additive in the broiler industry.

Meta-analysis of the effects of mycotoxins and yeast cell wall extract supplementation on the performance, livability, and environmental sustainability of broiler production

The effect of mycotoxins (MT) on broiler performance without or with the inclusion of yeast cell wall extract (YCWE, Mycosorb, Alltech, Inc., KY) was evaluated in a random-effects meta-analysis. Data was extracted from 25 research experiments with a total of 10,307 broilers. Broilers fed MT had lower (P < 0.001) body weight gain (BWG, −217 g), reduced feed intake (FI, −264 g), increased feed conversion ratio (FCR, 0.12), and greater mortality by 2.01%. Inclusion of YCWE improved (P < 0.001) BWG (59 g) and FI (65 g), lowered FCR (−0.05), and reduced mortality by 1.74%. Additionally, change in European Production Efficiency Factor (EPEF) was assessed. Feeding MT lowered (P < 0.001) EPEF while YCWE increased (P < 0.001) EPEF. Finally, the carbon footprint of production was evaluated. Control fed birds produced an estimated 1.93 kg CO2-equivalent/kg liveweight (LW), while MT fed broilers produced 2.13 kg CO2-equivalent/kg LW and YCWE inclusion lowered this to 2.03 kg CO2-equivalent/kg LW which resulted in −25 tonnes less CO2-equivalent output per 100,000 birds with YCWE. In conclusion, mycotoxins can play a role in reducing broiler performance and farm production output, as well as increase the carbon footprint. Inclusion of YCWE in feed under a mycotoxin challenge can improve broiler performance and output, as well as lower carbon footprint, which could play a role in farm efficiency, profitability, and environmental sustainability.

Impact of a Natural Fusarial Multi-Mycotoxin Challenge on Broiler Chickens and Mitigation Properties Provided by a Yeast Cell Wall Extract and a Postbiotic Yeast Cell Wall-Based Blend

Yeast cell wall-based preparations have shown efficacy against Aspergillus-based toxins but have lower impact against type-B trichothecenes. Presently, we investigated a combination of deoxynivalenol (DON), T-2 toxin (T2) and zearalenone (ZEA), and the effect of a yeast cell wall extract (YCWE) and a post-biotic yeast cell wall-based blend (PYCW) with the objectives of preventing mycotoxins’ negative effects in commercial broilers. A total of 720 one-day-old male Cobb broilers were randomly allocated to: (1) control diet, (aflatoxins 6 µg/kg; cyclopiazonic acid 15 µg/kg; fusaric acid 25 µg/kg; fumonisin B1 310 µg/kg); (2) Diet1 + 0.2% YCWE; (3) Diet1 + 0.2% PYCW; (4) Contaminated diet (3.0 mg/kg DON; 2.17 mg/kg 3-acetyldeoxynivalenol; 104 g/kg T2; 79 g/kg ZEA); (5) Diet4 + 0.2% YCWE; and (6) Diet4 + 0.2% PYCW. Naturally contaminated diets adversely affected performance, serum biochemistry, liver function, immune response, altered cecal SCFA goblet cell count and architecture of intestinal villi. These adverse effects were reduced in birds fed PYCW and to a lesser extent YCWE, indicating protection against toxic assault. PYCW yielded better production performance and stimulated liver function, with higher response to NDV and IBV vaccination. Furthermore, mycotoxins were found to affect production outputs when evaluated with the European poultry production efficiency factor compared to control or YCWE and PYCW supplemented treatments. Taken together, YCWE, when complemented with nutritional add-ons (PYCW), could potentiate the remediation of the negative effects from a multi mycotoxins dietary challenge in broiler birds.

Use of different adsorbents in broiler diets naturally contaminated by mycotoxins

This study investigated the effects of adding different adsorbent substances to broilers feed naturally contaminated by mycotoxins. Two hundred and eighty male 1-day-old chicks, Cobb Slow® lineage, were distributed in a randomized block design with 4 treatments, 5 repetitions with 14 birds each. The treatments consisted of: T1- basal feed naturally contaminated with mycotoxins. T2- basal feed + Bentonite, Thistle Extract, Yeast Extract, Vitamin E and Choline. T3- basal feed + Bentonite, Thistle Extract, yeast cell wall and Silymarin. T4- basal feed + Bentonite and Algae extract. Performance (weight gain, feed intake, feed conversion) at 7, 14, 21, 28 days were evaluated. At 28 days, a portion of the jejunum was collected in two birds by replicate to study the intestinal morphology. The relative weight of the gizzard, proventricle and total intestine was evaluated. The data obtained were analyzed using the statistical program SAS (9.3). With the use of any adsorbents studied, the performance and liver weight were improved in all evaluated periods. Thus, the inclusion of adsorbents improves the performance of the broiler chickens when the feed is contaminated by mycotoxins.

Deoxynivalenol: Mechanisms of action and its effects on various terrestrial and aquatic species

Deoxynivalenol, a type B trichothecene mycotoxin produced by Fusarium species of fungi, is a ubiquitious contaminant of cereal grains worldwide. Chronic, low dose consumption of feeds contaminated with DON is associated with a wide range of symptoms in terrestrial and aquatic species including decreased feed intake and feed refusal, reduced weight gain, and altered nutritional efficiency. Acute, high dose exposure to DON may be associated with more severe symptoms such as vomiting, diarrhea, intestinal inflammation and gastrointestinal hemorrhage. The toxicity of DON is partly related to its ability to disrupt eukaryotic protein synthesis via binding to the peptidyl transferase site of the ribosome. Moreover, DON exerts its effects at the cellular level by activating mitogen activated protein kinases (MAPK) through a process known as the ribotoxic stress response (RSR). The outcome of DON-associated MAPK activation is dose and duration dependent; acute low dose exposure results in immunostimulation characterized by the upregulation of cytokines, chemokines and other proinflammatory-related proteins, whereas longer term exposure to higher doses generally results in apoptosis, cell cycle arrest, and immunosuppression. The order of decreasing sensitivity to DON is considered to be: swine > rats > mice > poultry ≈ ruminants. However, studies conducted within the past 10 years have demonstrated that some species of fish, such as rainbow trout, are highly sensitive to DON. The aims of this review are to explore the effects of DON on terrestrial and aquatic species as well as its mechanisms of action, metabolism, and interaction with other Fusarium mycotoxins. Notably, a considerable emphasis is placed on reviewing the effects of DON on different species of fish.

Biomarkers of Deoxynivalenol Toxicity in Chickens with Special Emphasis on Metabolic and Welfare Parameters

Deoxynivalenol (DON), a trichothecene mycotoxin produced by Fusarium species, is the most widespread mycotoxin in poultry feed worldwide. Long term-exposure from low to moderate DON concentrations can produce alteration in growth performance and impairment of the health status of birds. To evaluate the efficacy of mycotoxin-detoxifying agent alleviating the toxic effects of DON, the most relevant biomarkers of toxicity of DON in chickens should be firstly determined. The specific biomarker of exposure of DON in chickens is DON-3 sulphate found in different biological matrices (plasma and excreta). Regarding the nonspecific biomarkers called also biomarkers of effect, the most relevant ones are the impairment of the productive parameters, the intestinal morphology (reduction of villus height) and the enlargement of the gizzard. Moreover, the biomarkers of effect related to physiology (decrease of blood proteins, triglycerides, hemoglobin, erythrocytes, and lymphocytes and the increase of alanine transaminase (ALT)), immunity (response to common vaccines and release of some proinflammatory cytokines) and welfare status of the birds (such as the increase of Thiobarbituric acid reactive substances (TBARS) and the stress index), has been reported. This review highlights the available information regarding both types of biomarkers of DON toxicity in chickens.

Effects of Deoxynivalenol-Contaminated Diets on Metabolic and Immunological Parameters in Broiler Chickens

The current study was conducted to examine the effects of deoxynivalenol (DON) at different levels (5 and 15 mg/kg feed) on the metabolism, immune response and welfare parameters of male broiler chickens (Ross 308) at 42 days old. Forty-five 1 day-old broiler chickens were randomly distributed into three different dietary treatments: (1) control, (2) DON-contaminated diet with 5 mg DON/kg of feed (guidance level), and (3) DON-contaminated diet with 15 mg DON/kg of feed. Five replicated cages with three birds each were used for each treatment in a randomized complete block design. The results showed that DON was detected in excreta of birds fed contaminated diets compared with controls. The metabolite DON-3 sulphate (DON-3S) was detected in plasma and excreta in both treated groups, as well as in the liver (but only at 15 mg/kg feed). The increase in the level of DON decreased the hemoglobin concentration (p < 0.001), whereas the erythrocyte counts were only decreased at 15 mg DON/kg feed. No effect of DON on the responses to common vaccines was observed. In plasma, interleukin 8 levels in both contaminated groups were significantly higher than in the control group. The expression of interleukin 6, interleukin 1β and interferon-γ increased in jejunum tissues of broilers fed 5 mg/kg of DON compared with controls. The stress index (heterophil to lymphocyte ratio) was not affected by DON-contaminated diets compared with controls. The plasma corticosterone level was significantly lower in both DON groups compared with controls. In conclusion, DON-3S could be used as a specific biomarker of DON in different biological matrices, while the immune response in broiler chickens is stimulated by the presence of DON at the guidance level, but no adverse effect was observed on physiological stress parameters.

Antidotal Potency of the Novel, Structurally Different Adsorbents in Rats Acutely Intoxicated with the T-2 Toxin

In this paper, the potential antidote efficacy of commercially available formulations of various feed additives such as Minazel-Plus^®, Mycosorb^®, and Mycofix^® was considered by recording their incidence on general health, body weight, and food and water intake, as well as through histopathology and semiquantitative analysis of gastric alterations in Wistar rats treated with the T-2 toxin in a single-dose regimen of 1.67 mg/kg p.o. (1 LD₅₀) for 4 weeks. As an organic adsorbent, Mycosorb^® successfully antagonized acute lethal incidence of the T-2 toxin (protective index (PI) = 2.25; p < 0.05 vs. T-2 toxin), and had adverse effects on body weight gain as well as food and water intake during the research (p < 0.001). However, the protective efficacy of the other two food additives was significantly lower (p < 0.05). Treatment with Mycosorb^® significantly reduced the severity of gastric damage, which was not the case when the other two adsorbents were used. Our results suggest that Mycosorb^® is a much better adsorbent for preventing the adverse impact of the T-2 toxin as well as its toxic metabolites compared with Minazel-plus^® or Mycofix-plus^®, and it almost completely suppresses its acute toxic effects and cytotoxic potential on the gastric epithelial, glandular, and vascular endothelial cells.

Impact of Chronic Levels of Naturally Multi-Contaminated Feed with Fusarium Mycotoxins on Broiler Chickens and Evaluation of the Mitigation Properties of Different Titers of Yeast Cell Wall Extract

The chronic intake of naturally multi-mycotoxin contaminated feed by broilers with or without titers of Yeast Cell Wall Extract (YCWE, a.k.a Mycosorb A+®), was investigated. Day-old male Cobb chicks (1600 birds, 64 pens, 25 birds/pen) were randomly allocated to diets of control (CON); diet containing mycotoxins (MT); CON + 0.2% YCWE; MT + 0.025% YCWE; MT + 0.05% YCWE; MT + 0.1% YCWE; MT + 0.2% YCWE; and MT + 0.4% YCWE. Growth performance, blood biochemical parameters and gut health were recorded over 42 days. Compared with CON, MT had reduced body weight (BW) and increased feed conversion ratio (FCR) on days 35 and 42 with increased duodenal crypt depth and fewer goblet cells. Furthermore, European Poultry Production Efficiency (EPEF) was reduced for MT versus CON. Feeding MT + 0.2% YCWE improved BW, lowered FCR, reduced crypt depth, increased goblet cell count and improved EPEF. Considering titration of YCWE (0 to 0.4%) during mycotoxin challenge, a cubic effect was observed for FCR with NC + 0.2% YCWE having the lowest FCR. These findings suggest that chronic consumption of multiple Fusarium mycotoxins present in common field concentrations can negatively impact broiler performance and gut health while inclusion of YCWE, particularly 0.2%, could be effective in counteracting mycotoxins.

Carry-over of some Fusarium mycotoxins in tissues and eggs of chickens fed experimentally mycotoxin-contaminated diets

Fusarium mycotoxins are fungal contaminants found in different crops intended for human and animal consumption. Due to the co-occurrence of several of mycotoxins, the present study aimed at examining the transfer of these toxins into tissues of broiler chickens and eggs of laying hens fed contaminated diets. After an adaptation period, the chickens were fed contaminated diets containing mg/kg levels of deoxynivalenol (DON), enniatins (ENN A, A₁, B, B₁) and beauvericin (BEA) and high μg/kg levels of HT-2 toxin (HT-2), T-2 toxin (T-2) and zearalenone (ZEN) during a repletion period of two weeks, followed by a depletion period of two weeks. DON, ZEN, T-2 and HT-2 were not carried out into the skin and the liver of broiler chickens. ENN B (20.5 ± 6.6 μg/kg) and BEA (162 ± 55 μg/kg) were found in the liver, while in the skin their respective concentrations were 50 ± 17 μg/kg and 120 ± 16 μg/kg during the first week of the repletion period. Carry-over rates into liver and skin were higher for BEA (1.6% and 1.2%, respectively) than for ENNs (0.1 and 0.4%, respectively). During the depletion period, ENNs and BEA were eliminated from the skin and the liver. ENN B, ENN B₁ and BEA were carried over into eggs at 0.1%, 0.05% and 0.44% upon 2-3 days of feeding the contaminated diet, respectively. These transfers were fully eliminated 9-10 days after feeding the control diet again. These results indicate the transfer of ENN B, ENN B₁ and BEA from feed to chicken offal, meat products and eggs at a very low degree, thus marginally contribute to the total dietary intake of these fusariotoxins for consumers. Nevertheless, taking precautionary measures in the field, harvest, transport and storage of the raw materials is required to keep the mycotoxin concentration in feed below the safe levels.

Microbiological Detoxification of Mycotoxins: Focus on Mechanisms and Advances

Some fungal species of the genera Aspergillus, Penicillium, and Fusarium secretes toxic metabolites known as mycotoxins, have become a global concern that is toxic to different species of animals and humans. Biological mycotoxins detoxification has been studied by researchers around the world as a new strategy for mycotoxin removal. Bacteria, fungi, yeast, molds, and protozoa are the main living organisms appropriate for the mycotoxin detoxification. Enzymatic and degradation sorptions are the main mechanisms involved in microbiological detoxification of mycotoxins. Regardless of the method used, proper management tools that consist of before-harvest prevention and after-harvest detoxification are required. Here, in this review, we focus on the microbiological detoxification and mechanisms involved in the decontamination of mycotoxins.

Effects of glycerol monolaurate on growth and physiology of chicks consuming diet containing fumonisin

Glycerol monolaurate (GML) is composed of lauric acid and glycerol. Research has shown that such organic acids can minimize negative effects caused by mycotoxins. Therefore, the objective of this study was to determine whether adding GML (free or encapsulated) to chick feed minimizes the effects of natural contamination by fumonisin (Fusarium verticillioides), evaluating parameters such as biochemistry, antioxidant properties, histological analysis and chick growth. Were weighed 84 chicks of the Cobb 500 strain and randomly distributed them into six groups of two replicates each (n = 14). The F group consumed feed containing fumonisin (levels 400 ppb), with no performance enhancer; F + ZB- feed with fumonisin (levels 400 ppb) + zinc bacitracin; F + GLM100 - feed with fumonisin (levels 400 ppb) + 100 mg of GML/kg of feed; F + NGLM4 - feed with fumonisin (levels 400 ppb) + 4 mg GML/kg in nanocapsules added to the feed; F + NGLM8 - fumonisin feed (levels 400 ppb) + 8 mg GML/kg in nanocapsules in the feed; and F0 - fumonisin-free feed (negative control) + zinc bacitracin. The body weights of birds fed with feed fumonisin-contaminated feed (F, F + ZB, F + GLM100, F + NGLM4 and F + NGLM8) were significantly lower (P < 0.05) than those of the negative control (F0), despite the use of GML (free and nanoencapsulated). Serum levels of triglycerides, globulins and cholesterol were significantly lower in the F0 group than in the other groups (P < 0.05), except for the F + NGLM8 group. Significantly greater levels of lipid peroxidation were observed in livers in the groups that consumed fumonisin than in the control group (F0) (P < 0.05). Serum levels of reactive oxygen species were significantly lower in groups F + NGLM8 and F0 than in the other treatments (P < 0.05). Superoxide dismutase activity was significantly greater in groups F + NGLM8 and F0 than in groups F, F + ZB and F + NGLM4. Hepatic catalase activity was significantly lower in birds that consumed contaminated feed (F, F + ZB, F + GLM100, F + NGLM4 and F + NGLM8) than in the control group (F0). Greater hepatic glutathione S-transferase activity was observed in the F + NGLM8 group than in the F0 group. Despite changes in cellular lesions in the liver, no histological changes were observed in the liver or intestines, even though visually there was yellowing of the liver. Taken together, the data suggest that free or nano-encapsulated GML did not minimize oxidative stress caused by fumonisin, and consequently, these birds had less weight gain.

Molecular docking and mechanisms of fusaric acid induced mitochondrial sirtuin aberrations in glycolytically and oxidatively poised human hepatocellular carcinoma (HepG2) cells

Fusaric acid (FA) is a ubiquitous yet neglected mycotoxin. The toxicity of FA is associated with mitochondrial dysfunction and oxidative stress. Sirtuins (SIRTs) are key mediators of cell stress responses through deacetylation of antioxidant, mitochondrial maintenance and energy metabolism proteins. Dietary bioactive compounds have profound effects on SIRT activity, however little is known regarding common foodborne toxins and SIRTs. In this study the interaction of FA with mitochondrial SIRTs - SIRT3 and SIRT5, were firstly studied by molecular docking. Thereafter we substantiated the in silico findings by investigating the effect of FA on expression profiles of SIRT3 and SIRT5, and transcriptional and post-transcriptional regulators, PGC-1α and miRNA-30c using western blots and qPCR in vitro. FA was predicted to bind to the active site of SIRT3 and SIRT5 having implications for biological activity. Furthermore, protein expression of SIRT3 and SIRT5 was down-regulated despite elevated mRNA levels. Further experimentation revealed post-transcriptional regulation of both SIRTs as evidenced by elevated miRNA-30c despite induction of PGC-1α. This study highlights the potential of a diet contaminated with FA to dysregulate mitochondrial specific proteins that can lead to initiation and progression of sirtuin related diseases including cancer and insulin resistance.

Feed preference and feeding behaviours in grower broilers fed diets containing wheat naturally contaminated with fusarium mycotoxins

1. Two trials were conducted to determine the effect of feeding diets contaminated with fusarium mycotoxins (primarily deoxynivalenol (DON)) on broiler chicken feed preference, feeding behaviour and growth performance. 2. A total of 120 male Ross 308 chicks (4 birds/cage, 30 cages) were fed a common corn-based starter diet from 1 to 20 d of age. At 21 d, 15 cages were randomly assigned to the feed preference trial or a feeding behaviour trial. Three wheat-based experimental diets (0.14, 2.27 and 5.84 mg/kg DON) were prepared with a clean wheat and a naturally contaminated wheat. Broilers were ad libitum fed the experimental diets during 21-27 d. 3. In the preference trial, each cage's feeder was split into two equal-sized compartments so birds were provided a choice of two diets (control vs. low, control vs. high and low vs. high DON). In the feeding behaviour trial, diets were randomly assigned to 15 cages (5 cages/diet). Feeding and drinking behaviour was recorded for 1 h before and after the dark period and 1-h period at 9 h after the light was turned on (middle of day). Growth performance was assessed at 27 d. 4. In the preference trial, broilers preferred the control diet over low (93.0 vs. 66.1 g/d, P < 0.01) and high (104.4 vs. 50.4 g/d, P < 0.01) DON diets. At all three timepoints, where behaviour was recorded, birds offered the DON diets spent more time at the feeder compared to birds provided control diets (P < 0.05). Control birds had lower feed to gain ratio (1.65) than birds fed low (1.82) and high (1.94) DON diets (P < 0.01). 5. It is clear that broilers are sensitive to the presence of fusarium mycotoxins and that moderate levels of DON negatively affect feed preference and growth performance when fed during the grower period.

Effect of dietary supplementation of mannanoligosaccharides on hepatic gene expressions and humoral and cellular immune responses in aflatoxin-contaminated broiler chicks

The present study was conducted to investigate the effects of dietary supplementation of mannanoligosaccharides (MOS) on expression of hepatic immunological genes and immune responses in aflatoxin-contaminated broiler chicks. A total of 336 seven-day-old Ross broiler chicks were randomly allotted to 7 experimental treatments with 4 replicates and 12 birds per replicate. Experimental treatments consisted of 2 aflatoxin levels (0.5 and 2 ppm) and 3 supplemental MOS levels (0, 1 and 2 g/kg) as a 2 × 3 factorial arrangement in comparison with a control group (unchallenged group). The chicks were challenged with a mix of aflatoxins during 7-28 d of age. Results showed that aflatoxin challenge resulted in the lower antibody titers against infectious bronchitis (IBV) and bursal (IBD) diseases viruses. In addition, aflatoxin-contaminated birds had a lower (P < 0.0001) lymphocyte percentage and a decline in (P < 0.01) interleukin-2 (IL-2) mRNA abundance. Likewise, heterophil proportion, heterophil to lymphocyte ratio and gene expressions of hepatic interleukin-6 (IL-6) and C reactive protein (CRP) were raised (P < 0.001) by increasing dietary aflatoxin level. Dietary inclusion of MOS increased (P < 0.05) antibody titers against IBV, IBD and Newcastle disease virus. Lymphocyte proportion and hepatic IL-2 gene expression were greater (P < 0.0001) in MOS-supplemented birds. Furthermore, supplemental MOS decreased hepatic IL-6 and CRP abundances. Additionally, inclusion of 2 g/kg MOS resulted in the upregulation (P < 0.01) of hepatic IL-2 gene expression in birds contaminated with 0.5 ppm aflatoxin. The present results indicate that supplemental MOS could improve cellular immunity via the upregulation of hepatic IL-2 gene expression in birds challenged with aflatoxins.

Performance effects of feed-borne Fusarium mycotoxins on broiler chickens: Influences of timing and duration of exposure

In commercial practice, broiler chickens may be exposed to Fusarium mycotoxins either during specific growth stages or throughout the entire production cycle. A 34-day feeding trial was conducted to identify sensitive periods for mycotoxin effects during the growth cycle of broiler chickens. A total of 420 newly-hatched Ross 308 male broilers were randomly assigned to 60 cages with 7 birds/cage. Sources of clean wheat (<0.5 mg/kg deoxynivalenol [DON]) and Fusarium-contaminated wheat (11.4 mg/kg DON) were used to formulate the starter diets (0.41 and 6.62 mg/kg DON) provided from 1 to 21 d of age and the grower diets (0.54 and 7.90 mg/kg DON) provided from 22 to 34 d. Control and DON diets were provided to broilers according to treatments (control, DON 1 to 14 d, DON 15 to 21 d, DON 22 to 34 d and DON 1 to 34 d). Birds were monitored daily for morbidity or mortality. Broiler growth performance (body weight, average daily gain, average daily feed intake and feed to gain ratio) was measured weekly. Segments of duodenum, jejunum and ileum were collected at 21 and 34 d and morphometric parameters (villus height, crypt depth, villus width, muscularis thickness and villi:crypt ratio) were measured. Birds fed the DON starter diet during the first 14 d did not exhibit any changes in growth performance; however, growth performance was suppressed in birds fed DON-contaminated diets during the grower period (22 to 34 d). At 34 d, birds that received the DON grower diet (DON 22 to 34 d and DON 1 to 34 d) were lighter (1,433 vs. 1,695 g) than birds fed the control diet. Feed to gain ratio was higher in birds fed the DON grower diet from 22 to 28 d (1.77 vs. 1.56) and 28 to 34 d (2.24 vs. 1.85) compared with corresponding controls. These results suggest that providing older broiler chicks (22 to 34 d) feed contaminated with Fusarium mycotoxins (specifically DON) may result in production losses. Histopathological analysis of the ileum region revealed that birds provided the DON diets throughout the entire trial (1 to 34 d) had shorter villi (506 vs. 680 μm) and shallower crypt (85 vs. 115 μm) than control birds. Taken together, these results indicate that DON-induced growth suppression may be a result of adverse effects on intestinal morphology during later growth phases of broilers.

A review of the mycotoxin adsorbing agents, with an emphasis on their multi-binding capacity, for animal feed decontamination

Contamination of animal feed with mycotoxins still occurs very often, despite great efforts in preventing it. Animal feeds are contaminated, at low levels, with several mycotoxins, particularly with those produced by Aspergillus and Fusarium genera (Aflatoxin B_1, Ochratoxin A, Zearalenone, Deoxynivalenol and Fumonisina B₁). In animal feed, to date, only Aflatoxin B₁ is limited through EU regulation. Consequently, mycotoxins cause serious disorders and diseases in farm animals. In 2009, the European Union (386/2009/EC) approved the use of mycotoxin-detoxifying agents, as feed additives, to prevent mycotoxicoses in farm animals. The present review gives an overview of the problem of multi-mycotoxin contamination of feed, and aims to classify mycotoxin adsorbing agents (minerals, organic, and synthetic) for feed decontamination, focusing on adsorbents with the ability to bind to multiple mycotoxins, which should have a more effective application in farms but they are still little studied in scientific literature.

Effects of low to moderate levels of deoxynivalenol on feed and water intake, weight gain, and slaughtering traits of broiler chickens

The aim of the study was to evaluate the effects of low to moderate oral exposure to the Fusarium toxin deoxynivalenol (DON; derived from culture material) on performance, water intake, and carcass parameters of broilers during early and late developmental phases. A total of 160 Ross 308 broilers were randomly allocated to four different feeding groups (n = 40/group) including 0 (control), 2.5, 5, and 10 mg DON/kg wheat-soybean meal-based feed. Three consecutive replicates of the experiment were performed. Half of the broilers were slaughtered in week 3 of the trial whereas the other half were slaughtered in week 5. Dry matter intake (DMI) and water intake (WI) were recorded on a daily basis and the body weight (BW) and BW gain (BWG) were determined weekly. The following carcass traits were recorded and calculated in absolute and relative data: dressed carcass weight, breast muscle weight, leg weight, and liver weight. Data showed that BW (P < 0.001), BWG (P = 0.005), and DMI (P < 0.001) were reduced by DON-feeding during the entire feeding period. The ratio of DMI to body weight gain (DMI/BWG) was not affected by the treatment. However, the ratio of water to DMI (WI/DMI) increased in DON-treated birds (P = 0.021). Contrast analysis showed that DON tendentially reduced slaughter weight (P = 0.082) and decreased leg yield (P = 0.037) in DON-fed chickens in week 5 of the experiment. Liver organ weight decreased in the 3-week-old DON-fed broilers compared to that in the control-fed birds (P = 0.037). In conclusion, the study suggests that DMI and BW were negatively affected under the experimental conditions at DON levels lower than the current guidance value in the European Union of 5 mg/kg feed. The study also indicates that broilers fed on low to moderate level DON-contaminated diets showed increased WI/DMI ratio which might have negative influence on wet litter syndrome.

Chronic Exposure to the Fusarium Mycotoxin Deoxynivalenol: Impact on Performance, Immune Organ, and Intestinal Integrity of Slow-Growing Chickens

This study investigates the long-term effects of deoxynivalenol (DON) consumption on avian growth performance, on the proliferation, apoptosis, and DNA damage of spleen cells, and on intestinal integrity. Two hundred and eight 5-day-old black-feathered Taiwan country chickens were fed diets containing 0, 2, 5, and 10 mg/kg of DON for 16 weeks. Body weight gain of male birds in the 2 mg/kg group was significantly lower than that in the 5 mg/kg group. At the end of trial, feeding DON-contaminated diets of 5 mg/kg resulted in heavier spleens. Moreover, the increase in DON induced cellular proliferation, apoptosis, and DNA damage signals in the spleen, the exception being female birds fed 10 mg/kg of DON showing reduced proliferation. Expression of claudin-5 was increased in jejunum of female birds fed 2 and 5 mg/kg of DON, whereas decreased expression levels were found in male birds. In conclusion, our results verified that DON may cause a disturbance to the immune system and alter the intestinal barrier in Taiwan country chickens, and may also lead to discrepancies in growth performances in a dose- and sex-dependent manner.

Toxicity of Mycotoxins from Contaminated Corn with or withoutYeast Cell Wall Adsorbent on Broiler Chickens

This study investigated the effects of feeds naturally contaminated with mycotoxins on growth performance, serum biochemical parameters, carcass traits, and splenic heat shock protein 70 (Hsp70) mRNA expression levels in broiler chickens. The efficacy of yeast cell wall (YCW) adsorbent in preventing mycotoxicosis was also evaluated. Three hundred 1-d-old Arbor Acres broiler chicks were randomly allotted to 3 treatments in completely randomized design for 42 d. Each treatment group had 5 replicate pens with 20 birds. The treatments were as follows: i) basal diet (control), ii) naturally contaminated diet (NCD), and iii) NCD+0.2% YCW adsorbent (NCDD). The NCD decreased average daily gain (ADG) (p<0.01) of 0 to 21 d, 22 to 42 d, and 0 to 42 d, and increased feed conversion ratio (p<0.01) of 22 to 42 d and 0 to 42 d. Both the breast meat percentage and thigh meat percentage of the NCD group were significantly higher (p<0.01) than that of the control group on d 21. The NCD group showed significantly increased levels of triglycerides (p<0.05) and cholesterol (p<0.05) on both d 21 and d 42 compared to the control group. However, the NCD significantly reduced (p<0.01) the high-density lipoprotein (HDL) on d 42 compared to controls. Compared with the NCD, supplementation with YCW significantly improved (p<0.01) the ADG of 0 to 21 d and 0 to 42 d, and increased (p<0.01) concentrations of HDL on d 42, and on d 21, and triglycerides (p<0.05) on d 21 and d 42. Supplementation with YCW reduced (p<0.01) the breast meat percentage, the thigh meat percentage, the concentrations of cholesterol (p<0.01) and the low-density lipoprotein (p<0.05) on d 21, and improved (p<0.01) the splenic Hsp70 mRNA expression levels compared with the NCD group. The results of this study indicated that feeding NCD for 42 d had adverse effects on broiler chickens, and that YCW might be beneficial in counteracting the effects of mycotoxins.

Insights on the host stress, fear and growth responses to the deoxynivalenol feed contaminant in broiler chickens

Mycotoxins pose an important danger to human and animal health. Poultry feeds are frequently contaminated with deoxynivalenol (DON) mycotoxin. It is thus of great importance to evaluate the effects of DON on the welfare related parameters in poultry industry. In the present study, the effects of contamination of broiler diet with 10 mg DON/kg feed on plasma corticosterone and heterophil to lymphocyte (H/L) ratio as indicators of stress, tonic immobility duration as an index for fear response and growth performance of broiler chickens were studied. In addition, the effect of a microbial feed additive either alone or in combination with DON contamination on these different aspects was also evaluated. The results showed that DON feeding significantly affected the welfare related parameters of broiler chickens. The feeding of DON contaminated diet resulted in an elevation of plasma corticosterone, higher H/L ratio and increased the fear levels as indicated by longer duration of tonic immobility reaction. Furthermore, DON reduced the body weight and body weight gain during the starter phase definitely at the second and third week. However, during grower phase, feeding of DON decreased the body weight at the fourth week and reduced the body gain at the fifth week. Addition of the microbial feed additive, a commercial antidote for DON mycotoxin, was able to overcome DON effects on stress index (H/L ratio), fearfulness and growth parameters of broilers. In conclusion, we showed for the first time that the DON feeding increased the underlying fearfulness and physiological stress responses of broilers and resulted in a reduction in the welfare status as indicated by higher plasma corticosterone, higher H/L ratio and higher fearfulness. Additionally, feeding the microbial feed additive was effective in reducing the adverse effects of DON on the bird's welfare and can improve the performance of broiler chickens.

The effects of feed-borne Fusarium mycotoxins and glucomannan in turkey poults based on specific and non-specific parameters

An experiment was conducted to investigate the effects of feeding grains naturally contaminated with Fusarium mycotoxins and a yeast derived glucomannan mycotoxin adsorbent (GMA) on selected specific and non-specific parameters in turkey poults. Two hundred and forty 1-day-old male turkey poults were fed the experimental diets for twelve weeks. Experimental diets were formulated with control grains, control grains+0.2% GMA, naturally-contaminated grains, or naturally-contaminated grains+0.2% GMA. Deoxynivalenol (DON) was the major contaminant of the contaminated grains and concentrations varied from 4.0 to 6.5 mg/kg in the contaminated diets. Non-specific parameters measured included: performance parameters, plasma biochemistry profiles, morphometry and CD8(+) T-lymphocyte counts in the duodenum. Plasma concentrations of DON and de-epoxydeoxynivalenol (DOM-1) were used as specific parameters. Performance parameters and plasma biochemistry were altered by the feeding of contaminated diets and GMA but this was not consistent throughout the trial. The feeding of contaminated diets reduced duodenal villus height and apparent villus surface area. This effect was prevented by GMA supplementation. The feeding of contaminated diets elevated total duodenal CD8(+) T-lymphocyte counts but this effect was not prevented by GMA. No significant differences were seen in plasma concentrations of DON and DOM-1 comparing birds fed contaminated and contaminated+GMA diets suggesting that GMA did not prevent DON absorption under these conditions.

The toxicological impacts of the Fusarium mycotoxin, deoxynivalenol, in poultry flocks with special reference to immunotoxicity

Deoxynivalenol (DON) is a common Fusarium toxin in poultry feed. Chickens are more resistant to the adverse impacts of deoxynivalenol (DON) compared to other species. In general, the acute form of DON mycotoxicosis rarely occurs in poultry flocks under normal conditions. However, if diets contain low levels of DON (less than 5 mg DON/kg diet), lower productivity, impaired immunity and higher susceptibility to infectious diseases can occur. The molecular mechanism of action of DON has not been completely understood. A significant influence of DON in chickens is the impairment of immunological functions. It was known that low doses of DON elevated the serum IgA levels and affected both cell-mediated and humoral immunity in animals. DON is shown to suppress the antibody response to infectious bronchitis vaccine (IBV) and to Newcastle disease virus (NDV) in broilers (10 mg DON/kg feed) and laying hens (3.5 to 14 mg of DON/kg feed), respectively. Moreover, DON (10 mg DON/kg feed) decreased tumor necrosis factor alpha (TNF-α) in the plasma of broilers. DON can severely affect the immune system and, due to its negative impact on performance and productivity, can eventually result in high economic losses to poultry producers. The present review highlights the impacts of DON intoxication on cell mediated immunity, humoral immunity, gut immunity, immune organs and pro-inflammatory cytokines in chickens.

Effects of feeding corn naturally contaminated with aflatoxin B1 and B2 on hepatic functions of broilers

The purpose of this study was to evaluate the effects of feeding corn naturally contaminated with aflatoxin B(1) (AFB(1)) and aflatoxin B(2) (AFB(2)) on serum biochemical parameters, hepatic antioxidant enzyme activities, and pathological lesions of broilers. In total, 1,200 Cobb male broilers were randomly allocated into 5 treatments, with 8 replicates per treatment and 30 birds per replicate, in a 42-d experiment. The dietary treatments were as follows: control, 25, 50, 75, and 100% contaminated corn groups. Results showed that serum aspartate aminotransferase activity in the 75 and 100% contaminated groups were higher than that in the control group on d 21 (P < 0.05). Decreased content of hepatic total protein and increased activities of hepatic glutathione reductase and glutathione-S-transferase were observed as the percentage of contaminated corn increased (P < 0.05). The activity of superoxide dismutase and the content of hepatic malondialdehyde increased when the broilers were fed with more than 50% contaminated corn (P < 0.05). A reduction in glutathione peroxidase level was observed in the AFB(1)- and AFB(2)-contaminated groups on d 21 (P < 0.05). The average pathological lesion scores and apoptosis rate of liver cells increased as the concentration of dietary AFB(1) and AFB(2) increased. Ultrastructural changes were found in the livers of broilers fed 100% contaminated corn. In conclusion, diets containing AFB(1) and AFB(2) could induce pathological lesions in the livers, slightly change the serum biochemical parameters, and damage the hepatic antioxidant functions when the inclusion of AFB(1)- and AFB(2)-contaminated corn reached or exceeded 50%.

Fusarium mycotoxin-contaminated wheat containing deoxynivalenol alters the gene expression in the liver and the jejunum of broilers

The effects of mycotoxins in the production of animal feed were investigated using broiler chickens. For the feeding trial, naturally Fusarium mycotoxin-contaminated wheat was used, which mainly contained deoxynivalenol (DON). The main effects of DON are reduction of the feed intake and reduced weight gain of broilers. At the molecular level, DON binds to the 60 S ribosomal subunit and subsequently inhibits protein synthesis at the translational level. However, little is known about other effects of DON, for example, at the transcriptional level. Therefore, a microarray analysis was performed, which allows the investigation of thousands of transcripts in one experiment. In the experiment, 20 broilers were separated into four groups of five broilers each at day 1 after hatching. The diets consisted of a control diet and three diets with calculated, moderate concentrations of 1.0, 2.5 and 5.0 mg DON/kg feed, which was attained by exchanging uncontaminated wheat with naturally mycotoxin-contaminated wheat up to the intended DON concentration. The broilers were held at standard conditions for 23 days. Three microarrays were used per group to determine the significant alterations of the gene expression in the liver (P < 0.05), and qPCR was performed on the liver and the jejunum to verify the results. No significant difference in BW, feed intake or feed conversion rate was observed. The nutrient uptake into the hepatic and jejunal cells seemed to be influenced by genes: SLC2A5 (fc: -1.54, DON2.5), which facilitates glucose and fructose transport and SLC7A10 (fc: +1.49, DON5), a transporter of d-serine and other neutral amino acids. In the jejunum, the palmitate transport might be altered by SLC27A4 (fc: -1.87, DON5) and monocarboxylates uptake by SLC16A1 (fc: -1.47, DON5). The alterations of the SLC gene expression may explain the reduced weight gain of broilers chronically exposed to DON-contaminated wheat. The decreased expressions of EIF2AK3 (fc: -1.29, DON2.5/5) and DNAJC3 (fc: -1.44, DON2.5) seem to be related to the translation inhibition. The binding of DON to the 60 S ribosomal subunit and the subsequent translation inhibition might be counterbalanced by the downregulation of EIF2AK3 and DNAJC3. The genes PARP1, MPG, EME1, XPAC, RIF1 and CHAF1B are mainly related to single-strand DNA modifications and showed an increased expression in the group with 5 mg DON/kg feed. The results indicate that significantly altered gene expression was already occurring at 2.5 mg DON/kg feed.

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

The aim of the present experiment was to investigate the effects of feeding grains naturally contaminated with Fusarium mycotoxins on morphometric indices of jejunum and to follow the passage of deoxynivalenol (DON) through subsequent segments of the digestive tract of broilers. A total of 45 1-d-old broiler chickens (Ross 308 males) were randomly allotted to three dietary treatments (15 birds/treatment): (1) control diet; (2) diet contaminated with 1 mg DON/kg feed; (3) diet contaminated with 5 mg DON/kg feed for five weeks. None of the zootechnical traits (body weight, body weight gain, feed intake, and feed conversion) responded to increased DON levels in the diet. However, DON at both dietary levels (1 mg and 5 mg DON/kg feed) significantly altered the small intestinal morphology. In the jejunum, the villi were significantly (P < 0.01) shorter in both DON treated groups compared with the controls. Furthermore, the dietary inclusion of DON decreased (P < 0.05) the villus surface area in both DON treated groups. The absolute or relative organ weights (liver, heart, proventriculus, gizzard, small intestine, spleen, pancreas, colon, cecum, bursa of Fabricius and thymus) were not altered (P > 0.05) in broilers fed the diet containing DON compared with controls. DON and de-epoxy-DON (DOM-1) were analyzed in serum, bile, liver, feces and digesta from consecutive segments of the digestive tract (gizzard, cecum, and rectum). Concentrations of DON and its metabolite DOM-1 in serum, bile, and liver were lower than the detection limits of the applied liquid chromatography coupled with mass spectrometry (LC-MS/MS) method. Only about 10 to 12% and 6% of the ingested DON was recovered in gizzard and feces, irrespective of the dietary DON-concentration. However, the DON recovery in the cecum as percentage of DON-intake varied between 18 to 22% and was not influenced by dietary DON-concentration. Interestingly, in the present trial, DOM-1 did not appear in the large intestine and in feces. The results indicate that deepoxydation in the present study hardly occurred in the distal segments of the digestive tract, assuming that the complete de-epoxydation occurs in the proximal small intestine where the majority of the parent toxin is absorbed. In conclusion, diets with DON contamination below levels that induce a negative impact on performance could alter small intestinal morphology in broilers. Additionally, the results confirm that the majority of the ingested DON quickly disappears through the gastrointestinal tract.

Assessment of the potential of a boron-fructose additive in counteracting the toxic effect of Fusarium mycotoxins

Trichotecenes are mycotoxins produced by Fusarium sp., which may contaminate animal feeds and human food. A feeding trial was conducted to evaluate the effect of a fusarotoxin-contaminated diet, and to explore the counteracting potential of a calcium fructoborate (CFrB) additive on performance, typical health biochemistry parameters and immune response in weaned pigs. A naturally contaminated maize, containing low doses of deoxynivalenol, zearalenone, fumonisins and T-2/HT-2 toxins (1790, 20, 0·6 and 90 parts per billion), was included in a maize-soyabean meal diet, and given ad libitum to eight weaned piglets (two groups: four pigs/group) for a period of 24 d. CFrB was administered to one of the contaminated groups and to another four piglets as a daily supplement, following the manufacturer's recommendation. A decrease in performance was observed in contaminated animals at this concentration of feed toxins, which was ameliorated by the dietary CFrB supplementation. Fusarium toxins also altered the pig immune response by increasing (P < 0·05) the ex vivo peripheral blood mononuclear cell proliferation (111·7 % in comparison with control), the respiratory burst of porcine granulocytes (15·4 % for responsive cells v. 5·1 % for unstimulated cells and 70·95 v. 22·65 % for stimulated cells, respectively), the percentage of peripheral T, CD3(+), CD3(+)CD4(+) and CD3(+)CD8(+) subsets and the synthesis of IL-1β, TNF-α and IL-8 (123·8, 217·1 and 255·1 %, respectively). The diet containing the CFrB additive reduced these exacerbated cellular immune responses induced by Fusarium toxins. However, consumption of CFrB did not counteract the effect of mycotoxins on biochemistry parameters, and increased plasma IgM and IgG of contaminated pigs.