Effects of prolonged exposure to low-dose fumonisin B1 in pigs

Effects of a Curcumin/Silymarin/Yeast-Based Mycotoxin Detoxifier on Redox Status and Growth Performance of Weaned Piglets under Field Conditions

The aim of this in vivo study was to investigate the effects of a novel mycotoxin detoxifier whose formulation includes clay (bentonite and sepiolite), phytogenic feed additives (curcumin and silymarin) and postbiotics (yeast products) on the health, performance and redox status of weaned piglets under the dietary challenge of fumonisins (FUMs). The study was conducted in duplicate in the course of two independent trials on two different farms. One hundred and fifty (150) weaned piglets per trial farm were allocated into two separate groups: (a) T1 (control group): 75 weaned piglets received FUM-contaminated feed and (b) T2 (experimental group): 75 weaned piglets received FUM-contaminated feed with the mycotoxin-detoxifying agent from the day of weaning (28 days) until 70 days of age. Thiobarbituric acid reactive substances (TBARSs), protein carbonyls (CARBs) and the overall antioxidant capacity (TAC) were assessed in plasma as indicators of redox status at 45 and 70 days of age. Furthermore, mortality and performance parameters were recorded at 28, 45 and 70 days of age, while histopathological examination was performed at the end of the trial period (day 70). The results of the present study reveal the beneficial effects of supplementing a novel mycotoxin detoxifier in the diets of weaners, including improved redox status, potential hepatoprotective properties and enhanced growth performance.

Combined Dietary Supplementation of Tenebrio molitor Larvae and Chitosan in Growing Pigs: A Pilot Study

Nowadays, the global animal industry faces considerable challenges in securing sufficient feed resources. Responding to consumer demands for reduced use of antibiotics in animal nutrition, better animal welfare status, and reduced impact on the environment, there is an increased urgency to develop innovative functional feeds with a reduced environmental footprint and the ability to improve meat quality and safety. In an effort to explore innovative feed ingredients for growing pig diets, the combined dietary supplementation of Tenebrio molitor larvae and chitosan was investigated. An experimental trial was performed with 48 weaned pigs (34 days of life; mixed sex) that were randomly assigned to four treatment groups (with six males and six females each): Group A (control), Group B (supplemented with T. molitor larvae at 10%), Group C (supplemented with chitosan at 0.05%), and Group D (supplemented with both ingredients at 10% and 0.05%, respectively). On the 42nd day of the experimental trial, samples of blood, feces, and carcass parts were taken for analysis. The results indicated that the insect larvae meal significantly improved (p < 0.05) overall performance, increased (p < 0.05) blood red blood cell content, increased meat phenolic content (p < 0.05), improved meat oxidative stability (p < 0.05), and affected meat fatty acid profile (p < 0.05). On the other hand, chitosan had no significant effect on overall performance (p > 0.05), but it significantly increased blood lymphocyte content (p < 0.05), affected the fecal microbiota (p < 0.05), improved meat oxidative stability (p < 0.05), increased meat phenolic content (p < 0.05), and affected meat fatty acid composition (p < 0.05) and (p < 0.05) meat color. Finally, the combined use of both T. molitor and chitosan significantly affected some important zootechnical parameters (p < 0.05), fecal microbial populations (p < 0.05), meat color (p < 0.05), and fatty acid profile (p < 0.05). Further investigation into the potential interaction between insect larvae meals and chitosan in pig diets is advised.

Assessment of information as regards the toxicity of fumonisins for pigs, poultry and horses

In 2018, the EFSA Panel on Contaminants in the Food Chain (CONTAM) adopted a Scientific Opinion on the risks for animal health related to the presence of fumonisins, their modified forms and hidden forms in feed. A no observed adverse effect level (NOAEL) of 1 mg/kg feed was established for pigs. In poultry a NOAEL of 20 mg/kg feed and in horses a reference point for adverse animal health effect of 8.8 mg/kg feed was established, referred to as NOAEL. The European Commission (EC) requested EFSA to review the information regarding the toxicity of fumonisins for pigs, poultry and horses and to revise, if necessary, the established NOAELs. The EFSA CONTAM Panel considered that the term reference point (RP) for adverse animal health effects better reflects the uncertainties in the available studies. New evidence which had become available since the previous opinion allowed to revise an RP for adverse animal health effects for poultry from 20 mg/kg to 1 mg/kg feed (based on a LOAEL of 2.5 mg/kg feed for reduced intestinal crypt depth) and for horses from 8.8 to 1.0 mg/kg feed (based on case studies on equine leukoencephalomalacia (ELEM)). For pigs, the previously established NOAEL was confirmed as no further studies suitable for deriving an RP for adverse animal health effects could be identified. Based on exposure estimates performed in the previous opinion, the risk of adverse health effects of feeds containing FB1-3 was considered a concern for poultry, when taking into account the RP of 1 mg/kg feed for intestinal effects. For horses and other solipeds, the risk is considered low, although a large uncertainty associated with exposure was identified. The same conclusions apply to the sum of FB1-3 and their hidden forms.

Mycotoxin Biomarkers in Pigs-Current State of Knowledge and Analytics

Farm animals are frequently exposed to mycotoxins, which have many adverse effects on their health and become a significant food safety issue. Pigs are highly exposed and particularly susceptible to mycotoxins, which can cause many adverse effects. For the above reasons, an appropriate diagnostic tool is needed to monitor pig' exposure to mycotoxins. The most popular tool is feed analysis, which has some disadvantages, e.g., it does not include individual exposure. In recent years, the determination of biomarkers as a method to assess the exposure to mycotoxins by using concentrations of the parent compounds and/or metabolites in biological matrices is becoming more and more popular. This review provides a comprehensive overview of reported in vivo mycotoxin absorption, distribution, metabolism and excretion (ADME) and toxicokinetic studies on pigs. Biomarkers of exposure for aflatoxins, deoxynivalenol, ochratoxin A, fumonisins, T-2 toxin and zearalenone are described to select the most promising compound for analysis of porcine plasma, urine and faeces. Biomarkers occur in biological matrices at trace levels, so a very sensitive technique-tandem mass spectrometry-is commonly used for multiple biomarkers quantification. However, the sample preparation for multi-mycotoxin methods remains a challenge. Therefore, a summary of different biological samples preparation strategies is included in that paper.

Fumonisin-containing diets decrease the metabolic activity of myenteric neurons in rats

Fumonisins are naturally occurring mycotoxins that contaminate food for human and animal consumption. They have neurotoxic effects, but the mechanisms by which these toxins affect the nervous system are not fully known. In the present study, male Wistar rats were fed between 21 and 63 days of age with diets that contained fumonisins B₁+B₂ at 0, 1, and 4 mg/kg. The following variables were assessed: food consumption, growth, body weight gain, and blood parameters. Morphoquantitave analyses of the most metabolically active myenteric neurons were performed, detected by NADH-diaphorase activity. Nitrergic neurons were detected by NADPH-diaphorase activity. The fumonisin-containing diets did not significantly alter food consumption or the body or plasma parameters. These diets decreased the metabolic activity of jejunal myenteric neurons, reducing neuronal density of the most metabolic active neurons by 30.8% and the cell body area by 4.3%. The diets also decreased the cell body area of nitrergic neurons by 22.1%. The effects of fumonisin B₁ on the respiratory metabolism of isolated mitochondria in the brain and liver were also assessed. A decrease in oxygen consumption up to a 29% in the brain and 38% in the liver was observed in mitochondrial isolates to which 50 µM fumonisin B₁ was added. The decrease in respiratory activity that was triggered by exposure to fumonisins was related to the lower metabolic activity of myenteric neurons, which had a negative impact on neuroplasticity of the enteric nervous system.

Effects of Fumonisin-Contaminated Corn on Growth Performance of 9 to 28 kg Nursery Pigs

Fumonisin contamination in corn is an emerging issue in animal feed production. Fumonisin disrupts the metabolism of sphingolipids and reduces growth performance. This experiment was conducted to determine the effect of feeding fumonisin-contaminated corn on growth performance and sphinganine (SA) to sphingosine (SO) ratios of 9 to 28 kg pigs. A total of 350 pigs, were used with 5 pigs/pen and 14 pens/treatment. Dietary treatments contained fumonisin-contaminated corn (50 mg/kg of fumonisin B1 + B2) blended with low fumonisin corn (10 mg/kg of fumonisin B1 + B2) to provide dietary fumonisin concentrations of 7.2, 14.7, 21.9, 32.7, and 35.1 mg/kg. From day 0 to 28, increasing fumonisin concentration decreased (linear, p < 0.001) average daily gain, average daily feed intake (linear, p = 0.055), and gain:feed ratio (linear, p = 0.016). Although these response criteria tested linear, the greatest reduction in performance was in pigs fed with 32.7 and 35.1 mg/kg of fumonisin (B1 + B2). Increasing fumonisin concentration increased the serum SA:SO ratio (linear, p < 0.001) on day 14 and 28. In summary, for 9 to 28 kg nursery pigs, increasing fumonisin linearly decreased average daily gain and gain:feed ratio. However, despite the linear response, diets containing up to 21.9 mg/kg of fumonisin did not have as dramatic a decrease in growth performance as those fed more than 32.7 mg/kg. Further research is warranted to determine the effect of fumonisin concentrations between 21.9 and 32.7 mg/kg.

Fumonisins at Doses below EU Regulatory Limits Induce Histological Alterations in Piglets

Fumonisins (FBs) are mycotoxins produced by Fusarium species that can contaminate human food and animal feed. Due to the harmful effects of FBs on animals, the European Union (EU) defined a recommendation of a maximum of 5 mg FBs (B1 + B2)/kg for complete feed for swine and 1 µg FBs/kg body weight per day as the tolerable daily intake for humans. The aim of this study was to evaluate the toxicity of dietary exposure to low doses of FBs, including a dose below the EU regulatory limits. Four groups of 24 weaned castrated male piglets were exposed to feed containing 0, 3.7, 8.1, and 12.2 mg/kg of FBs for 28 days; the impact was measured by biochemical analysis and histopathological observations. Dietary exposure to FBs at a low dose (3.7 mg/kg of feed) significantly increased the plasma sphinganine-to-sphingosine ratio. FBs-contaminated diets led to histological modifications in the intestine, heart, lung, lymphoid organs, kidney, and liver. The histological alterations in the heart and the intestine appeared at the lowest dose of FBs-contaminated diet (3.7 mg/kg feed) and in the kidney at the intermediate dose (8.1 mg/kg feed). At the highest dose tested (12.2 mg/kg feed), all the organs displayed histological alterations. This dose also induced biochemical modifications indicative of kidney and liver alterations. In conclusion, our data indicate that FBs-contaminated diets at doses below the EU regulatory limit cause histological lesions in several organs. This study suggests that EU recommendations for the concentration of FBs in animal feed, especially for swine, are not sufficiently protective and that regulatory doses should be modified for better protection of animal health.

Risks for animal health related to the presence of fumonisins, their modified forms and hidden forms in feed

Fumonisins, mycotoxins primarily produced by Fusarium verticillioides and Fusarium proliferatum, occur predominantly in cereal grains, especially in maize. The European Commission asked EFSA for a scientific opinion on the risk to animal health related to fumonisins and their modified and hidden forms in feed. Fumonisin B1 (FB 1), FB 2 and FB 3 are the most common forms of fumonisins in feedstuffs and thus were included in the assessment. FB 1, FB 2 and FB 3 have the same mode of action and were considered as having similar toxicological profile and potencies. For fumonisins, the EFSA Panel on Contaminants in the Food Chain (CONTAM) identified no-observed-adverse-effect levels (NOAELs) for cattle, pig, poultry (chicken, ducks and turkeys), horse, and lowest-observed-adverse-effect levels (LOAELs) for fish (extrapolated from carp) and rabbits. No reference points could be identified for sheep, goats, dogs, cats and mink. The dietary exposure was estimated on 18,140 feed samples on FB 1-3 representing most of the feed commodities with potential presence of fumonisins. Samples were collected between 2003 and 2016 from 19 different European countries, but most of them from four Member States. To take into account the possible occurrence of hidden forms, an additional factor of 1.6, derived from the literature, was applied to the occurrence data. Modified forms of fumonisins, for which no data were identified concerning both the occurrence and the toxicity, were not included in the assessment. Based on mean exposure estimates, the risk of adverse health effects of feeds containing FB 1-3 was considered very low for ruminants, low for poultry, horse, rabbits, fish and of potential concern for pigs. The same conclusions apply to the sum of FB 1-3 and their hidden forms, except for pigs for which the risk of adverse health effect was considered of concern.

Appropriateness to set a group health-based guidance value for fumonisins and their modified forms

The EFSA Panel on Contaminants in the Food Chain (CONTAM) established a tolerable daily intake (TDI) for fumonisin B1 (FB 1) of 1.0 μg/kg body weight (bw) per day based on increased incidence of megalocytic hepatocytes found in a chronic study with mice. The CONTAM Panel considered the limited data available on toxicity and mode of action and structural similarities of FB 2-6 and found it appropriate to include FB 2, FB 3 and FB 4 in a group TDI with FB 1. Modified forms of FBs are phase I and phase II metabolites formed in fungi, infested plants or farm animals. Modified forms also arise from food or feed processing, and include covalent adducts with matrix constituents. Non-covalently bound forms are not considered as modified forms. Modified forms of FBs identified are hydrolysed FB 1-4 (HFB 1-4), partially hydrolysed FB 1-2 (pHFB 1-2), N-(carboxymethyl)-FB 1-3 (NCM-FB 1-3), N-(1-deoxy-d-fructos-1-yl)-FB 1 (NDF-FB 1), O-fatty acyl FB 1, N-fatty acyl FB 1 and N-palmitoyl-HFB 1. HFB 1, pHFB 1, NCM-FB 1 and NDF-FB 1 show a similar toxicological profile but are less potent than FB 1. Although in vitro data shows that N-fatty acyl FBs are more toxic in vitro than FB 1, no in vivo data were available for N-fatty acyl FBs and O-fatty acyl FBs. The CONTAM Panel concluded that it was not appropriate to include modified FBs in the group TDI for FB 1-4. The uncertainty associated with the present assessment is high, but could be reduced provided more data are made available on occurrence, toxicokinetics and toxicity of FB 2-6 and modified forms of FB 1-4.

Safety of low and high cost dry feed intended for dogs in Brazil concerning fumonisins, zearalenone and aflatoxins

The Brazilian pet sector exportation has been growing at an impressive rate lately. Considering the intense globalisation, pet food may be commercialised worldwide and the issue concerning safety of dry dog feed has become a topic of widespread international interest. Therefore, the objectives of this study were to evaluate the safety of low and high cost dry feed and the degree of exposure of dogs to mycotoxins through naturally contaminated feed in Brazil. In addition, the safe pet dietary level (SPDL) was calculated. Fumonisins, zearalenone (ZEA) and aflatoxins were analysed in three feed types intended for dogs (n=87), provided by pet owners. Mean fumonisin levels were 272 µg/kg (Standard), 78.2 µg/kg (Premium), and 186 µg/kg (Super Premium) while ZEA mean levels were 52.6 µg/kg (Standard), 10.6 µg/kg (Premium) and 17.5 µg/kg (Super Premium). Mean total aflatoxin levels (aflatoxin B1 + B2 + G1 + G2) in Standard, Premium and Super Premium feed were 1.29 µg/kg, 0.49 µg/kg and 0.53 µg/kg, respectively. The estimated daily intake (EDI) values for fumonisin B1 were 1.41 (Standard), 1.60 (Premium) and 0.93 µg/kg body weight (BW)/day (Super Premium feed), whereas for ZEA they were 0.54 (Standard), 0.37 (Premium) and 0.42 µg/kg BW/day (Super Premium feed). SPDL for fumonisins and ZEA was 2,000 and 375 µg/kg feed, respectively. EDI values for aflatoxin B1 were 13.0 (Standard), 14.0 (Premium) and 11.0 ng/kg BW/day (Super Premium feed). Although the feed samples intended for dogs in Brazil were often contaminated with aflatoxins, fumonisins and ZEA, the estimated daily intake values were low, even for the low cost formulations. However, it cannot be excluded that some of the feed samples could have a negative effect on animal health and performance considering feeding a monodiet of commercial feed, low multi-mycotoxin contamination levels and interactions between mycotoxins.

Efficacy of dietary spray dried plasma protein to mitigate the negative effects on performance of pigs fed diets with corn naturally contaminated with multiple mycotoxins

The ability of spray dried plasma protein (SDPP) to reduce the negative effects of multiple mycotoxins from naturally contaminated corn on weaned pig performance and health was investigated (n = 180; 6.84 ± 0.11 kg). For 12 d after weaning, pigs were fed phase 1 nursery diets with either 0% SDPP (PP0) or 6% SDPP (PP6). After 12 d, pigs were fed phase 2 diets for 3 wk. Pigs fed PP0 in phase 1 continued to be fed a phase 2 diet with no SDPP (PP0/PP0) or were fed a diet including corn naturally contaminated with multiple mycotoxins (M), labeled PP0/PP0M. Pigs fed SDPP in phase 1 were fed either a diet with no SDPP (PP6/PP0), a diet with M and no SDPP (PP6/PP0M), a diet with M and 3% SDPP (PP6/PP3M), or a diet with M and 6% SDPP (PP6/PP6M). During phase 1, pigs fed PP6 had increased (P < 0.05) ADG, ADFI, and G:F, whereas immunological parameters were not altered. During phase 2, pigs consuming PP0/PP0M had reduced ADG (P < 0.01) and ADFI (P < 0.05) in contrast to pigs fed PP0/PP0, whereas the performance of pigs fed PP6/PP0M was intermediate to pigs fed PP0/PP0M and PP6/PP0. The ADG and ADFI did not differ for pigs fed PP0/PP0M and PP6/PP0M during phase 2. Performance of pigs fed PP6/PP3M in contrast to pigs fed PP6/PP0M during phase 2 did not differ; however, these pigs had lower (P < 0.05) tumor necrosis factor α and tended (P = 0.094) to have lower DNA damage. During phase 2, ADG and ADFI of pigs fed PP6/PP6M did not differ from pigs fed PP6/PP0M, but G:F tended (P = 0.067) to be increased in pigs fed PP6/PP6M. Over the entire study period, pigs fed PP0/PP0M had reduced (P < 0.05) ADG and tended (P = 0.067) to have reduced ADFI. During this time, pigs fed PP6/PP0M tended to have greater ADG and ADFI (P = 0.093 and P = 0.067, respectively) compared with pigs fed PP0/PP0M. Overall, feeding a diet with SDPP improved growth performance and feed intake of young pigs directly after weaning. Feeding multiple M had a negative impact on growth performance of pigs during this trial. This response was more significant when pigs were not fed SDPP in phase 1. Overall, when combining phase 1 and 2 performance data, daily gain and feed intake tended to be reduced when pigs were not fed 6% SDPP in phase 1. This study indicates that the composition of diets fed immediately after weaning may be important for pigs that subsequently are under a M challenge.

Analyses of black Aspergillus species of peanut and maize for ochratoxins and fumonisins

The genus Aspergillus section Nigri, or the black aspergilli, represents genetically closely related species that produce the mycotoxins, ochratoxins and the fumonisins. Fumonisin B1 (FB1) is of an added concern because it is also a virulence factor for maize. Our preliminary data indicated that black aspergilli could develop asymptomatic infections with maize and peanuts plants. Symptomless infections are potential problems, because under favorable conditions, there is a potential for accumulation of ochratoxins and the fumonisins in contaminated postharvest crops. In the present report, the ability of black aspergilli from peanuts and maize to produce ochratoxin A and FB1 on maize kernels was assessed. One hundred fifty strains from peanuts and maize were isolated from several southeastern and midwestern states. Aspergillus nigri (A. nigri var. nigri) was the dominant species (87%), while Aspergillus foetidus, Aspergillus japonicus, Aspergillus tubingensis, and Aspergillus carbonarius were infrequently isolated. None of the wild isolates produced detectable amounts of ochratoxins. However, we do report the occurrence of the fumonisins B1, B2, and B3. Of 54 field isolates, 30% (n = 16) produced FB1, 61% (n = 33) produced FB2, and 44% (n = 24) produced FB3. The amounts of fumonisins produced during the test period of 30 days suggest that these strains might be weak to moderate producers of fumonisin on maize. To our knowledge, this is a first report of FB1 and FB3 production by isolates of black aspergilli from an American cereal and legume.

Effect of low dose of fumonisins on pig health: immune status, intestinal microbiota and sensitivity to Salmonella

The objective of this study was to measure the effects of chronic exposure to fumonisins via the ingestion of feed containing naturally contaminated corn in growing pigs infected or not with Salmonella spp. This exposure to a moderate dietary concentration of fumonisins (11.8 ppm) was sufficient to induce a biological effect in pigs (Sa/So ratio), but no mortality or pathology was observed over 63 days of exposure. No mortality or related clinical signs, even in cases of inoculation with Salmonella (5 × 10⁴ CFU), were observed either. Fumonisins, at these concentrations, did not affect the ability of lymphocytes to proliferate in the presence of mitogens, but after seven days post-inoculation they led to inhibition of the ability of specific Salmonella lymphocytes to proliferate following exposure to a specific Salmonella antigen. However, the ingestion of fumonisins had no impact on Salmonella translocation or seroconversion in inoculated pigs. The inoculation of Salmonella did not affect faecal microbiota profiles, but exposure to moderate concentrations of fumonisins transiently affected the digestive microbiota balance. In cases of co-infection with fumonisins and Salmonella, the microbiota profiles were rapidly and clearly modified as early as 48 h post-Salmonella inoculation. Therefore under these experimental conditions, exposure to an average concentration of fumonisins in naturally contaminated feed had no effect on pig health but did affect the digestive microbiota balance, with Salmonella exposure amplifying this phenomenon.

Effects of chronic exposure of diets with reduced concentrations of aflatoxin and deoxynivalenol on growth and immune status of pigs

This study investigated the growth and immune responses of pigs fed diets containing reduced concentrations of aflatoxin (AF) and deoxynivalenol (DON) from naturally contaminated corn. Sixty gilts (13.9 ± 0.2 kg of BW) were randomly assigned to 4 treatments (5 replicate pens per treatment and 3 pigs per pen): A (a control diet without detectable AF and DON); B (a diet with 60 μg of AF/kg and 300 μg of DON/kg); C (a diet with 120 μg of AF/kg and 600 μg of DON/kg); and D (a diet with 180 μg of AF/kg and 900 μg of DON/kg). Pigs were allowed ad libitum access to feed and water for 33 d. Feed intake and BW were measured weekly and pigs were bled (8 mL) on d 33 to measure the numbers of blood cells, to conduct liver function tests, and to measure immunological variables including IgG, IgM, interferon γ, IL4, IL6, and tumor necrosis factor α. One pig representing the average BW of each pen was killed to obtain the liver, kidneys, and spleen for weight, tissue color measurement, and histological evaluation of tissue damage. When compared with A, pigs in C and D tended to have reduced ADG (0.52 vs. 0.43 and 0.41 kg/d, respectively; P = 0.058) and ADFI (1.04 vs. 0.92 and 0.88 kg/d, respectively; P = 0.061). White blood cell count of pigs in D (23.4 × 10(3) cells/μL) was greater (P < 0.05) than those in A, B, and C (18.4, 18.5, and 16.8 × 10(3) cells/μL, respectively. Serum tumor necrosis factor α concentration of pigs in D (335 pg/mL) differed (P < 0.05) from those in A and C (299 and 290 pg/mL, respectively). Pigs in B and D had greater (P < 0.05) fibrosis in liver tissues than those in A. Collectively, this study shows that diets containing both AF and DON greater than 60 and 300 μg/kg, respectively, may reduce growth and decrease feed intake, whereas diets containing 120 μg of AF/kg and 600 μg of DON/kg may result in altered immune health, systemic inflammation, and partial liver damage, causing further reduction in growth of pigs.

Chronic toxicity of fumonisins in turkeys

Fumonisins are mycotoxins that are found worldwide. They are mainly produced by Fusarium verticillioides during its development on corn. The main toxic effects of these molecules have been well characterized in poultry in the case of acute exposure, but the subclinical and economic effects of chronic exposure are less known. Whereas the latest European recommendations suggest that maximal levels of fumonisins in corn could reach 60 mg/kg and the maximal contamination of poultry feeds could reach 20 mg/kg, no study is available at this level in turkeys. The aim of the present work was thus to characterize the effects of exposure to fumonisins (concentrations of 0, 5, 10, and 20 mg of fumonisin B1 + fumonisin B2/kg of feed) on feed consumption and growth in turkeys over a period of 9 wk. Main biochemical parameters of the liver and alteration of sphingolipid metabolism were investigated in plasma, liver, and kidney. The main results showed no effect on feed consumption and growth in exposed turkeys. Moreover, no effect was observed on the weight of tissues and markers of liver injury. By contrast, a disruption of sphingolipid metabolism was clear at a level of exposure of 10 and 20 mg of fumonisin B1 + fumonisin B2 mg/kg of feed. Both hepatic and kidney concentrations of sphinganine increased gradually throughout the exposure period. These results reveal that disruption of sphingolipid metabolism is an early and sensitive biomarker of fumonisins exposure in turkeys; the consequences on these alterations remain to be established.

Sex-related differences in the immune response of weanling piglets exposed to low doses of fumonisin extract

Fumonisin B1 (FB1) is a mycotoxin produced by Fusarium verticillioides, a fungus that commonly contaminates maize. Sex-related effects of FB1 have been observed with respect to carcinogenicity in rodents, to performances in pigs and immunosuppression in mice. In the present study the sex-related effect of FB1 on the pig immune response was determined. Female and castrated male piglets received for 28 d either control feed or feed contaminated with 8 mg FB1/kg feed in the form of F. verticillioides culture material. At day 7 and day 21, animals were immunised subcutaneously with a Mycoplasma agalactiae vaccine. Ingestion of FB1-contaminated feed significantly decreased weight gain in males but had no effect in females. No sex-related difference was observed in biochemical parameters, but a higher level of creatinine was noted in toxin-treated animals. FB1 also altered the pig immune response in a sex-specific manner. In males, ingestion of FB1-contaminated feed significantly decreased specific antibody levels after vaccination as well as the mRNA expression level of IL-10. In females, the toxin has no effect on specific antibodies or on cytokine mRNA levels. The results of the present study indicate that FB1 is immunosuppressive in pigs. The magnitude of this FB1-induced immunosuppression is highly dependent on sex, with males being more susceptible than females.

Oral exposure to culture material extract containing fumonisins predisposes swine to the development of pneumonitis caused by Pasteurella multocida

Fumonisin B(1) (FB(1)) is a mycotoxin produced by Fusarium verticillioides and F. proliferatum that commonly occurs in maize. In swine, consumption of contaminated feed induces liver damage and pulmonary edema. Pasteurella multocida is a secondary pathogen, which can generate a respiratory disorder in predisposed pigs. In this study, we examined the effect of oral exposure to fumonisin-containing culture material on lung inflammation caused by P. multocida. Piglets received by gavage a crude extract of fumonisin, 0.5mg FB(1)/kg body weight/day, for 7 days. One day later, the animals were instilled intratracheally with a non toxin producing type A strain of P. multocida and followed up for 13 additional days. Pig weight and cough frequency were measured throughout the experiment. Lung lesions, bronchoalveolar lavage fluid (BALF) cell composition and the expression of inflammatory cytokines were evaluated at the autopsy. Ingestion of fumonisin culture material or infection with P. multocida did not affect weight gain, induced no clinical sign or lung lesion, and only had minimal effect on BALF cell composition. Ingestion of mycotoxin extract increased the expression of IL-8, IL-18 and IFN-gamma mRNA compared with P. multocida infection that increased the expression of TNF-alpha. The combined treatment with fumonisin culture material and P. multocida delayed growth, induced cough, and increased BALF total cells, macrophages and lymphocytes. Lung lesions were significantly enhanced in these animals and consisted of subacute interstitial pneumonia. TNF-alpha, IFN-gamma and IL-18 mRNA expression was also increased. Taken together, our data showed that fumonisin culture material is a predisposing factor to lung inflammation. These results may have implications for humans and animals consuming FB(1) contaminated food or feed.

Chronic effects of fumonisin B1 on ducks

Partially purified fumonisin B1 (FB1) was orally administrated for 77 d to 5 groups of 8 mule ducks starting at 7 d of age; the concentrations corresponded to 5 diets containing 0, 2, 8, 32, and 128 mg of FB1/kg of feed. No mortality was observed, and no effects on feed consumption and body weight gain were observed at the end of the treatment period. But, surprisingly, FB1 ingested at 32 and 128 mg/kg led to decreased body weight from d 28 to 63 and from d 7 to 63, respectively. FB1 had no effect on the relative weight of heart and breast muscle, whereas a significant increases in the relative weights of gizzard, spleen, and liver were measured in ducks receiving 32 and 128 mg of FB1/kg of feed without evidence of detectable microscopic modification of these organs. FB1 had no significant effect of the serum aspartate aminotransferase and gamma-glutamyltransferase levels but increased serum total protein, cholesterol, alanine aminotransferase, lactate dehydrogenase, alkaline phosphatase levels when 128 mg of FB1/kg of feed was given. Serum, liver, and kidney sphinganine to sphingosine ratio was significantly increased in ducks fed 8 to 128 mg of FB1/kg of feed. The biggest increase was observed in kidneys, suggesting that this organ is the most sensitive to detect FB1-induced disruption of sphingolipid metabolism.

Mycotoxin fumonisin B1 increases intestinal colonization by pathogenic Escherichia coli in pigs

Fumonisin B(1) (FB(1)) is a mycotoxin that commonly occurs in maize. FB(1) causes a variety of toxic effects in different animal species and has been implicated as a contributing factor of esophageal cancers in humans. In the present study, we examined the effect of dietary exposure to FB(1) on intestinal colonization by pathogenic Escherichia coli associated with extraintestinal infection. Three-week-old weaned pigs were given FB(1) by gavage as a crude extract or as a purified toxin at a dose of 0.5 mg/kg of body weight daily for 6 days. On the last day of the toxin treatment, the pigs were orally inoculated with an extraintestinal pathogenic E. coli strain. All animals were euthanized 24 h later, necropsies were performed, and tissues were taken for bacterial counts and light microscopic examination. Ingestion of FB(1) had only a minimal effect on animal weight gain, did not cause any macroscopic or microscopic lesions, and did not change the plasma biochemical profile. However, colonization of the small and large intestines by an extraintestinal pathogenic E. coli strain was significantly increased. Our results show that FB(1) is a predisposing factor to infectious disease and that the pig can be used as a model for the study of the consequences of ingesting mycotoxin-contaminated food.