Effects of Adding Clostridium sp. WJ06 on Intestinal Morphology and Microbial Diversity of Growing Pigs Fed with Natural Deoxynivalenol Contaminated Wheat

Expression, characterization, and application of an aldo-keto reductase mined from Bacillus velezensis Vel-HNGD-F2 for deoxynivalenol biodegradation

Deoxynivalenol (DON) contamination in cereals and their products poses a potential threat to animal and human health, however, physical and chemical detoxification methods deplete nutrients and cannot specifically remove DON. This study aims to identify novel and efficient DON-degrading enzymes, providing practical support for their application in biodegradation. A novel DON-degrading aldo-keto reductase named AKR11A2 was identified from Bacillus velezensis Vel-HNGD-F2 through BlastP comparison. AKR11A2, an enzyme with a molecular mass of 34.8 kDa encoded by a 933 bp gene, exhibited optimal activity at pH 9 and 40 °C, while demonstrating remarkable thermal and alkaline stability by retaining over 90% of its activity. UPLC-MS/MS analysis revealed that the m/z of the DON degradation product was 295.1, identified as 3-epi-DON, formed through the direct isomerization of DON. Notably, zebrafish experiments demonstrated that the liver toxicity of the degradation product was significantly lower than that of DON. AKR11A2 effectively degraded 50.69% of the DON in contaminated corn, highlighting its practical application in food safety. These findings indicate that the study achieved the biodegradation of DON and provide a promising theoretical and technological support for the application of DON detoxifying enzymes in food and feed products.

Fungi in the Gut Microbiota: Interactions, Homeostasis, and Host Physiology

The mammalian gastrointestinal tract is a stage for dynamic inter-kingdom interactions among bacteria, fungi, viruses, and protozoa, which collectively shape the gut micro-ecology and influence host physiology. Despite being a modest fraction, the fungal community, also referred to as mycobiota, represents a critical component of the gut microbiota. Emerging evidence suggests that fungi act as early colonizers of the intestine, exerting a lasting influence on gut development. Meanwhile, the composition of the mycobiota is influenced by multiple factors, with diet, nutrition, drug use (e.g., antimicrobials), and physical condition standing as primary drivers. During its establishment, the mycobiota forms both antagonistic and synergistic relationships with bacterial communities within the host. For instance, intestinal fungi can inhibit bacterial colonization by producing alcohol, while certain bacterial pathogens exploit fungal iron carriers to enhance their growth. However, the regulatory mechanisms governing these complex interactions remain poorly understood. In this review, we first introduce the methodologies for studying the microbiota, then address the significance of the mycobiota in the mammalian intestine, especially during weaning when all 'primary drivers' change, and, finally, discuss interactions between fungi and bacteria under various influencing factors. Our review aims to shed light on the complex inter-kingdom dynamics between fungi and bacteria in gut homeostasis and provide insights into how they can be better understood and managed to improve host health and disease outcomes.

Efficacy of High-Dose Synbiotic Additives for Deoxynivalenol Detoxification: Effects on Blood Biochemistry, Histology, and Intestinal Microbiome in Weaned Piglets

Deoxynivalenol (DON) is a common mycotoxin observed in cereal grains, and feed contamination poses health risks to pigs. Biological antidotes, such as synbiotics (SYNs), have garnered attention for mitigating DON toxicity. This study aimed to assess the efficacy of SYNs by comparing the blood biochemistry, histology, and gut microbiome of weaned piglets. A 4-week trial was conducted on 32 weaned piglets. After a week of diet and environmental adaptation, the pigs were divided into four groups: (1) control (CON, n = 8); (2) SYN (n = 8); (3) DON (n = 8); and (4) DON+SYN (n = 8). The SYN supplementation of weaned piglets increased the final body weight (21.71 ± 0.93 vs. 20.73 ± 0.84), average daily gain (0.38 ± 0.02 vs. 0.34 ± 0.02), and gain-to-feed ratio (0.49 ± 0.04 vs. 0.43 ± 0.02), and decreased the feed conversion ratio (2.14 ± 0.14 vs. 2.39 ± 0.13) compared to the DON group. A high dose of DON induced liver and colon fibrosis and liver and cecum apoptosis, which were alleviated by SYNs. Glucose in the DON group (84.9 ± 3.7) was significantly lower than in the control (101.3 ± 4.2). Additionally, both the DON and DON+SYN groups exhibited higher creatine (0.9 ± 0.0 and 0.9 ± 0.1) and lower cholesterol (88.3 ± 3.2 and 90.0 ± 4.8) levels (p < 0.05). In conclusion, SYNs alleviated DON toxicity, indicating its potential as an antidote for specific biomarkers.

Mitigation effects of plant carbon black on intestinal morphology, inflammation, antioxidant status, and microbiota in piglets challenged with deoxynivalenol

Introduction

Plant carbon black (PCB) is a new feed additive for zearalenone adsorption in China. However, information regarding whether PCB can effectively absorb deoxynivalenol (DON) is limited.

Methods

To explore this research gap, the present study examined the adsorption effectiveness of DON by PCB using a phosphate buffer, artificial gastric juice, and artificial intestinal juice. In a 21-day in vivo trial, 48 male piglets were randomly assigned to four treatment groups: (1) uncontaminated basal diet (CTR), (2) basal diet supplemented with 1 mg/kg PCB(PCB), (3) 2.3 mg/kg DON-contaminated diet (DON), and (4) 2.3 mg/kg DON-contaminated diet supplemented with 0.1% PCB (DON+PCB).

Results

When DON concentration was 1 µg/mL, the adsorption rate of PCB on DON in phosphate buffer systems (pH 2.0 and 6.0) and the artificial gastric and intestinal juices were 100%, 100%, 71.46%, and 77.20%, respectively. In the in vivo trial, the DON group significantly increased the DON+deepoxy-deoxynivalenol (DOM-1) content in serum as well as the inflammation cytokine proteins (interleukin-6, interleukin-8, and tumor necrosis factor-α) and mRNA expression of interleukin-6 and longchain acyl-CoA synthetase 4 in the jejunum and ileum. It decreased the villus height, goblet cells, mucosal thickness, and mRNA expression of Claudin-1 compared to the CTR group. In addition, DON decreased the Shannon and Simpson indices; reduced the relative abundances of Firmicutes, Lactobacillus, Candidatus_Saccharimonas, and Ruminococcus; and increased the relative abundances of Terrisporobacter and Clostridium_sensu_stricto_1 in the cecal content.

Discussion

In conclusion, these results suggest that PCB showed high adsorption efficacy on DON in vitro, and exhibit the protective effects against various intestinal toxicity manifestations in DON-challenged piglets.

Effects of dietary deoxynivalenol on growth performance and organ accumulation of growing pigs

OBJECTIVE

The present study aimed to study effects of a chronic feeding of deoxynivalenol (DON) on growth performance, organ weight, organ DON accumulation, and blood parameters in pigs.

METHODS

Forty-eight castrated male pigs with a body weight of 10.4 kg (standard deviation = 1.7) were assigned to one of 2 diet groups in a randomized complete block design with 6 blocks of pens per diet and 4 pigs per pen. A corn-soybean meal-based control diet was prepared to contain a low DON concentration of 0.28 mg/kg. Corn distillers dried grains with solubles naturally contaminated with DON were used at 30.0% to prepare a contaminated diet with a high DON concentration of 1.8 mg/kg. During the 56-day experimental period, body weight and feed intake were recorded every 14 days. A pig from each pen was euthanized for the collection of organs and muscle every 14 days.

RESULTS

Gain:feed in pigs fed the contaminated diet during days 14 to 28 and days 28 to 42 were less (p<0.05) compared with the control group. As increasing feeding period, the DON concentrations in fresh liver increased during days 14 to 28 and then decreased during the subsequent periods in the DON group, whereas the DON concentrations in fresh liver were constant during the experimental period in the control group (quadratic interaction p = 0.049). The DON concentration in the kidneys in the DON group was greater (p = 0.002) than that in the control group regardless of feeding period. On day 56, the granulocyte count in the DON group was less (p = 0.035) than the control group.

CONCLUSION

A chronic feeding of DON for 14 to 42 days decreased gain:feed in pigs, and dietary DON naturally contaminated in corn distillers dried grains with solubles accumulated in the liver during days 14 to 28.

Are Infants and Children at Risk of Adverse Health Effects from Dietary Deoxynivalenol Exposure? An Integrative Review

Deoxynivalenol (DON) is a foodborne mycotoxin produced by Fusarium molds that commonly infect cereal grains. It is a potent protein synthesis inhibitor that can significantly impact humans' gastrointestinal, immune, and nervous systems and can alter the microbiome landscape. Low-dose, chronic exposure to DON has been found to stimulate the immune system, inhibit protein synthesis, and cause appetite suppression, potentially leading to growth failure in children. At higher doses, DON has been shown to cause immune suppression, nausea, vomiting, abdominal pain, headache, diarrhea, gastroenteritis, the malabsorption of nutrients, intestinal hemorrhaging, dizziness, and fever. A provisional maximum tolerable daily intake (PMTDI) limit of 1 µg/kg/body weight has been established to protect humans, underscoring the potential health risks associated with DON intake. While the adverse effects of dietary DON exposure have been established, healthcare communities have not adequately investigated or addressed this threat to child health, possibly due to the assumption that current regulatory exposure limits protect the public appropriately. This integrative review investigated whether current dietary DON exposure rates in infants and children regularly exceed PMTDI limits, placing them at risk of negative health effects. On a global scale, the routine contamination of cereal grains, bakery products, pasta, and human milk with DON could lead to intake levels above PMTDI limits. Furthermore, evidence suggests that other food commodities, such as soy, coffee, tea, dried spices, nuts, certain seed oils, animal milk, and various water reservoirs, can be intermittently contaminated, further amplifying the scope of the issue. Better mitigation strategies and global measures are needed to safeguard vulnerable youth from this harmful toxicant.

Utilization of a Novel Soil-Isolated Strain Devosia insulae FS10-7 for Deoxynivalenol Degradation and Biocontrol of Fusarium Crown Rot in Wheat

Deoxynivalenol (DON) is the most widespread mycotoxin contaminant hazardous to human and animal health globally. It acts as a crucial virulence factor to stimulate the spread of pathogenic Fusarium within wheat plants. Control of DON and Fusarium disease contributes enormously to food safety, which relies on chemical fungicides. Here, we report the biodegradation of DON using a novel soil bacterium, Devosia insulae FS10-7, and its biocontrol effect against Fusarium crown rot. We demonstrated that strain FS10-7 degraded DON to 3-epi-DON by forming a 3-keto-DON intermediate. Such degradation activity can be maintained at a wide range of pH (4 to 10) and temperature (16 to 42°C) values under aerobic conditions. Notably, strain FS10-7 exhibited practical inhibitory effects on Fusarium crown rot disease caused by F. graminearum and F. pseudograminearum in the in vitro Petri dish test under laboratory conditions and the pot experiment under greenhouse conditions. The mechanisms underlying the biocontrol ability of strain FS10-7 were preliminarily investigated to be associated with its high DON-degrading activity rather than direct antagonism. These results establish the foundation to develop further bioagents capable of biodegrading mycotoxins in cereals and derived products and, accordingly, biocontrol plant diseases caused by DON-producing pathogens.

A comprehensive review of biodetoxification of trichothecenes: Mechanisms, limitations and novel strategies

Trichothecenes are Fusarium mycotoxins with sesquiterpenoid structure, which are widely occurred in grains. Due to high efficiency and environmental friendliness, biological detoxification methods have been of great interest to treat this global food and feed safety concern. This review summarized the biological detoxification methods of trichothecenes from three aspects, biosorption, biotransformation and biotherapy. The detoxification efficiency, characteristics, mechanisms and limitations of different strategies were discussed in detail. Computer-aided design will bring a new research paradigm for more efficient discovery of biodetoxifier. Integrating different detoxification approaches assisted with computational tools will become a promising research direction in the future, which will help to maximize the detoxification effect, or provide precise detoxification programs for the coexistence of various toxins at different levels in actual production. In addition, technical and regulatory issues in practical application were also discussed. These findings contribute to the exploration of efficient, applicable and sustainable methods for trichothecenes detoxification, ensuring the safety of food and feed to reduce the deleterious effects of trichothecenes on humans and animals.

Agaro-oligosaccharides mitigate deoxynivalenol-induced intestinal inflammation by regulating gut microbiota and enhancing intestinal barrier function in mice

Agarose-derived agaro-oligosaccharides (AgaroS) have been extensively studied in terms of structures and bioactivities; they reportedly possess antioxidant and anti-inflammatory activities that maintain intestinal homeostasis and host health. However, the protective effects of AgaroS on deoxynivalenol (DON)-induced intestinal dysfunction remain unclear. We investigated the effects of AgaroS on DON-induced intestinal dysfunction in mice and explored the underlying protective mechanisms. In total, 32 mice were randomly allocated to four treatments (n = 8 each) for 28 days. From day 1 to day 21, the control (CON) and DON groups received oral phosphate-buffered saline (200 μL per day); the AgaroS and AgaroS + DON groups received 200 mg AgaroS per kg body weight once daily by orogastric gavage. Experimental intestinal injury was induced by adding DON (4.8 mg per kg body weight) via gavage from day 21 to day 28. Phosphate-buffered saline was administered once daily by gavage in the CON and AgaroS groups. Herein, AgaroS supplementation led to a higher final body weight and smaller body weight loss and a lower concentration of plasma inflammatory cytokines, compared with the DON group. The DON group showed a significantly reduced ileal villus height and villus height/crypt depth, compared with the CON and AgaroS + DON groups. However, AgaroS supplementation improved DON-induced intestinal injury in mice. Compared with the DON group, ileal and colonic protein expression levels of claudin, occludin, Ki67, and mucin2 were significantly higher in the AgaroS supplementation group. Colonic levels of the anti-inflammatory cytokine IL-1β tended to be higher in the DON group than in the AgaroS + DON group. AgaroS altered the gut microbiota composition, accompanied by increased production of short-chain fatty acids in mice. In conclusion, our findings highlight a promising anti-mycotoxin approach whereby AgaroS alleviate DON-induced intestinal inflammation by modulating intestinal barrier functional integrity and gut microbiota in mice.

Identification and application of a novel deoxynivalenol-degrading enzyme from Youhaiella tibetensis

Deoxynivalenol (DON) poses a significant threat to human health due to its widespread distribution and biological toxicity. Here, we identified a novel DON-degrading enzyme from Youhaiella tibetensis (YoDDH). YoDDH exhibited the highest activity against DON at pH 4.5 and 40 ℃, in the presence of Ca2+ and the pyrroloquinoline quinone (PQQ). Additionally, YoDDH displayed remarkable thermostability at 40 ℃, with a half-life of 24 h and a Tm value of 48.5 ℃. Notably, phenazine methosulfate (PMS) and 2,6-dichlorophenolindophenol (DCPIP) can also serve as electron acceptors for YoDDH. After incubation in the optimal conditions for 3 h, YoDDH degraded 73 % of DON (100 μM) finally. The kcat and kcat /Km of YoDDH towards DON was determined as 1.65 s-1 and 1526 M-1·s-1 in the presence of PMS. The 3-keto-DON was verified as the degradation product. This identified YoDDH presents a promising candidate for DON decontamination in the food and feed industry.

Self-cascade deoxynivalenol detoxification by an artificial enzyme with bifunctions of dehydrogenase and aldo/keto reductase from genome mining

Due to the severe health risks for human and animal caused by the intake of toxic deoxynivalenol (DON) derived from Fusarium species, elimination DON in food and feed has been initiated as a critical issue. Enzymatic cascade catalysis by dehydrogenase and aldo-keto reductase represents a fascinating strategy for DON detoxification. Here, one quinone-dpendent alcohol dehydrogenase DADH oxidized DON into less-toxic 3-keto-DON and NADPH-dependent aldo-keto reductase AKR13B3 reduced 3-keto-DON into relatively non-toxic 3-epi-DON were identified from Devosia strain A6-243, indicating that degradation of DON on C3 are two-step sequential cascade processes. To establish the bifunctions, fusion enzyme linking DADH and AKR13B3 was successfully assembled to promote one-step DON degradations with accelerated specific activity and efficiency, resulting 93.29 % of DON removal rate in wheat sample. Three-dimensional simulation analysis revealed that the bifunctional enzyme forms an artificial intramolecular channel to minimize the distance of intermediate from DADH to AKR13B3 for two-step enzymatic reactions, and thereby accelerates this enzymatic process. As the first report of directing single step DON detoxification by an interesting bifunctional artificial enzyme, this work revealed a facile and eco-friendly approach to detoxify DON with application potential and gave valuable insights into execute other mycotoxin detoxification for ensuring food safety.

Degradation of deoxynivalenol by a microbial consortia C1 from duck intestine

Deoxynivalenol (DON), one of the most widespread mycotoxins in food and feed, poses a persistent health threat to humans and farm animals, and is difficult to eliminate. The utilization of the biotransformation mechanism by microorganisms to detoxify DON is a promising strategy. Although individual strains are capable of DON degradation, their isolation and purification are challenging and time-consuming. Recently, the microbial consortia concept has been proposed, owing to their ability to perform more complex tasks and are more tolerant to environmental changes than individual strains or species. In this study, the novel microbial consortia C1 that could efficiently convert DON to de-epoxy DON (DOM-1) was screened from the cecum contents of ducks. After 24 h anaerobic incubation, 100 μg/ml DON was completely degraded by C1. In vitro, C1 can effectively degrade DON in corn steep liquor (CSL) with an efficiency of 49.44% within 14 days. Furthermore, C1 effectively alleviated the DON poisoning in mice. After C1 treatment, the serum DON level decreased by 40.39%, and the reduction in serum total protein and albumin levels were mitigated. Additionally, C1 is effective in protecting the mouse liver against 5 mg/kg DON. These findings suggest that C1 could be a promising DON biological detoxifier and provide novel microbial resources for preventing DON contamination.

Global distribution, toxicity to humans and animals, biodegradation, and nutritional mitigation of deoxynivalenol: A review

Deoxynivalenol (DON) is one of the main types of B trichothecenes, and it causes health-related issues in humans and animals and imposes considerable challenges to food and feed safety globally each year. This review investigates the global hazards of DON, describes the occurrence of DON in food and feed in different countries, and systematically uncovers the mechanisms of the various toxic effects of DON. For DON pollution, many treatments have been reported on the degradation of DON, and each of the treatments has different degradation efficacies and degrades DON by a distinct mechanism. These treatments include physical, chemical, and biological methods and mitigation strategies. Biodegradation methods include microorganisms, enzymes, and biological antifungal agents, which are of great research significance in food processing because of their high efficiency, low environmental hazards, and drug resistance. And we also reviewed the mechanisms of biodegradation methods of DON, the adsorption and antagonism effects of microorganisms, and the different chemical transformation mechanisms of enzymes. Moreover, nutritional mitigation including common nutrients (amino acids, fatty acids, vitamins, and microelements) and plant extracts was discussed in this review, and the mitigation mechanism of DON toxicity was elaborated from the biochemical point of view. These findings help explore various approaches to achieve the best efficiency and applicability, overcome DON pollution worldwide, ensure the sustainability and safety of food processing, and explore potential therapeutic options with the ability to reduce the deleterious effects of DON in humans and animals.

Mycotoxin deoxynivalenol-induced intestinal flora disorders, dysfunction and organ damage in broilers and pigs

Deoxynivalenol (DON) is a common environmental contaminant that causes food refusal and growth retardation in animals. DON targets the intestine and is hazardous to animal, however, it is not clear whether its effect on animals is consistent. Chickens and pigs are the two main animals affected by DON exposure with different susceptibilities. In this study, we found that DON inhibited animal growth and caused damage to the intestine, liver and kidney. DON caused intestinal flora disorders in both chickens and pigs, such as changes of flora diversity and the relative abundance of dominant phyla. Functional analysis showed that changes in the intestinal flora induced by DON were mainly related to metabolic and digestive functions, indicated that the intestinal flora may be associated with the DON-induced intestinal dysfunction. Comparative analysis of differentially altered bacteria suggested that Prevotella may play an important role in maintaining intestinal health, and the presence of differentially altered bacteria in the two animals suggested that DON may have different toxicity modes in animals. In summary, we confirmed the multi-organ toxicity of DON in two major livestock and poultry animals, and speculated that the intestinal flora may be related to the toxic damage caused by DON through species comparison analysis.

Post-Harvest Prevention of Fusariotoxin Contamination of Agricultural Products by Irreversible Microbial Biotransformation: Current Status and Prospects

Biological degradation of mycotoxins is a promising environmentally-friendly alternative to chemical and physical detoxification methods. To date, a lot of microorganisms able to degrade them have been described; however, the number of studies determining degradation mechanisms and irreversibility of transformation, identifying resulting metabolites, and evaluating in vivo efficiency and safety of such biodegradation is significantly lower. At the same time, these data are crucial for the evaluation of the potential of the practical application of such microorganisms as mycotoxin-decontaminating agents or sources of mycotoxin-degrading enzymes. To date, there are no published reviews, which would be focused only on mycotoxin-degrading microorganisms with the proved irreversible transformation of these compounds into less toxic compounds. In this review, the existing information about microorganisms able to efficiently transform the three most common fusariotoxins (zearalenone, deoxinyvalenol, and fumonisin B1) is presented with allowance for the data on the corresponding irreversible transformation pathways, produced metabolites, and/or toxicity reduction. The recent data on the enzymes responsible for the irreversible transformation of these fusariotoxins are also presented, and the promising future trends in the studies in this area are discussed.

Crosstalk between Mycotoxins and Intestinal Microbiota and the Alleviation Approach via Microorganisms

Mycotoxins are secondary metabolites produced by fungus. Due to their widespread distribution, difficulty in removal, and complicated subsequent harmful by-products, mycotoxins pose a threat to the health of humans and animals worldwide. Increasing studies in recent years have highlighted the impact of mycotoxins on the gut microbiota. Numerous researchers have sought to illustrate novel toxicological mechanisms of mycotoxins by examining alterations in the gut microbiota caused by mycotoxins. However, few efficient techniques have been found to ameliorate the toxicity of mycotoxins via microbial pathways in terms of animal husbandry, human health management, and the prognosis of mycotoxin poisoning. This review seeks to examine the crosstalk between five typical mycotoxins and gut microbes, summarize the functions of mycotoxins-induced alterations in gut microbes in toxicological processes and investigate the application prospects of microbes in mycotoxins prevention and therapy from a variety of perspectives. The work is intended to provide support for future research on the interaction between mycotoxins and gut microbes, and to advance the technology for preventing and controlling mycotoxins.

Elephant grass supplementation in the feed of fattening pigs affects growth performance, carcass characteristics, blood profiles and intestinal microorganisms

To investigate the effects of the dietary inclusion of elephant grass on the growth performance, blood profiles, carcass characteristics, ileum and stomach microbiota of fattening pigs, pigs were fed one of seven diets including a basal diet (Control), and six treatments, where the basal diet was supplemented with 10%, 15% or 20% of elephant grass, Cenchrus purpureus cv. Guiminyin (CpGui10, CpGui15, CpGui20) or cv. Purple (CpP10, CpP15, CpP20). Results showed that supplementation of 20% CpGui in the diet significantly increased (P &lt; 0.05) average daily gain (ADG) and gain to feed (G/F) ratio by the end of the experiment. Additionally, pigs fed the CpGui20 diet showed higher (0.01 &lt; P &lt; 0.05) slaughter weight and tended to have increased loin-eye area and lean meat percentage, and, decreased backfat thickness compared with control pigs. Furthermore, 16S ribosomal DNA gene amplicon profiling showed that the inclusion of elephant grass in the diet was associated with modulation of the ileum and stomach microbiota composition at the order level. Relative abundance of the Lactobacillales order in the ileum and stomach increased with different proportions of elephant grass, while that of Enterobacteriales decreased. In conclusion, these results indicate that at up to 20% inclusion in the diet of pigs, elephant grass can promote enhanced growth performance and carcass characteristics, and, modulate the ileum and stomach microbiota composition of the pigs.

FumDSB can alleviate the inflammatory response induced by fumonisin B1 in growing pigs

Fumonisin B₁ (FB₁) has the highest natural contamination rate among all fumonisin analogs and can inhibit food intake and weight gain of pigs. Under laboratory conditions, carboxylesterase FumDSB has a high FB₁ degradation rate and excellent pH and thermal stability. The present study sought to estimate the effects of FumDSB on growing pigs from the perspective of a brain-intestinal axis. Twenty-four growing pigs of similar weight were divided into Control, FB₁ (5 mg FB₁/kg feed), and FumDSB (5 mg FB₁/kg and 0.1% FumDSB in the feed) groups. After 42 days of feeding, hypothalamus and jejunum samples were collected for quantitative real-time fluorescence, western blotting, and immunohistochemistry. The results showed that FB₁ consumption can destruct the tissue structure of hypothalamus and jejunum, affect the expression and distribution of several appetite-related neuropeptides and inflammatory cytokines, thereby inducing neuroinflammatory responses and affecting food intake and weight gain. However, these anorexia effects and inflammatory responses are alleviated when FumDSB is added to the feed. In short, FumDSB can alleviate the inflammatory response induced by FB₁ in growing pigs.

Protective effects of biological feed additives on gut microbiota and the health of pigs exposed to deoxynivalenol: a review

Deoxynivalenol (DON) is the most common mycotoxin contaminant of cereal-based food and animal feed. The toxicity of DON is very low compared to that of other toxins; however, the most prominent signs of DON exposure include inappetence and body weight loss, which causes considerable economic losses in the livestock industry. This review summarizes critical studies on biological DON mycotoxin mitigation strategies and the respective in vitro and in vivo intestinal effects. Focus areas include growth performance, gut health in terms of intestinal histomorphology, epithelial barrier functions, the intestinal immune system and microflora, and short-chain fatty acid production in the intestines. In addition, DON detoxification and modulation of these parameters, through biological supplements, are discussed. Biological detoxification of DON using microorganisms can attenuate DON toxicity by modulating gut microbiota and improving gut health with or without influencing the growth performance of pigs. However, the use of microorganisms as feed additives to livestock for mycotoxins detoxification needs more research before commercial use.

Effects of Fumonisin B and Hydrolyzed Fumonisin B on Growth and Intestinal Microbiota in Broilers

Fumonisins are mainly produced by Fusarium verticillioides and proliferatum, which causes a variety of toxicities in humans and animals, including fumonisin Bs (FBs) as the main form. After they are metabolized by plants or microorganisms, modified fumonisins are difficult to detect by conventional methods, which result in an underestimation of their contamination level. Fumonisins widely contaminate maize and maize products, especially in broiler feed. As an economically important food, broilers are often adversely affected by mycotoxins, leading to food safety hazards and high economic losses. However, there are few studies regarding the adverse effects of FBs on broiler growth and health, especially modified FBs. Our data shows that after exposure to FBs or hydrolyzed fumonisin Bs (HFBs), the body weight and tissue weight of broilers decreased significantly, especially the testes. Moreover, they significantly affect the intestinal microbiota and the relative abundance of bacteria from phylum-to-species levels, with the differentially affected bacteria mainly belonging to Firmicutes and Proteobacteria. Our findings suggest that both the parent and hydrolyzed FBs could induce growth retardation, tissue damage and the imbalance of intestinal microbiota in broilers. This indicated that the harmful effects of HFBs cannot be ignored during food safety risk assessment.

FumDSB Can Reduce the Toxic Effects of Fumonisin B1 by Regulating Several Brain-Gut Peptides in Both the Hypothalamus and Jejunum of Growing Pigs

Fumonisin B₁ (FB₁) is the most common food-borne mycotoxin produced by the Fusarium species, posing a potential threat to human and animal health. Pigs are more sensitive to FB₁ ingested from feed compared to other farmed livestock. Enzymatic degradation is an ideal detoxification method that has attracted much attention. This study aimed to explore the functional characteristics of the carboxylesterase FumDSB in growing pigs from the perspective of brain–gut regulation. A total of 24 growing pigs were divided into three groups. The control group was fed a basal diet, the FB₁ group was supplemented with FB₁ at 5 mg/kg feed, and the FumDSB group received added FumDSB based on the diet of the FB₁ group. After 35 days of animal trials, samples from the hypothalamus and jejunum were analyzed through HE staining, qRT-PCR and immunohistochemistry. The results demonstrated that the ingestion of FB₁ can reduce the feed intake and weight gain of growing pigs, indicating that several appetite-related brain-gut peptides (including NPY, PYY, ghrelin and obestatin, etc.) play important roles in the anorexia response induced by FB₁. After adding FumDSB as detoxifying enzymes, however, the anorexia effects of FB₁ were alleviated, and the expression and distribution of the corresponding brain-gut peptides exhibited a certain degree of regulation. In conclusion, the addition of FumDSB can reduce the anorexia effects of FB₁ by regulating several brain-gut peptides in both the hypothalamus and the jejunum of growing pigs.

Different metabolites induced by deoxynivalenol in the serum and urine of weaned rabbits detected using LC-MS-based metabolomics

The main toxic effects of deoxynivalenol (DON) are the result of long-term accumulation, and there are no obvious clinical signs at the early stage. Specific metabolites in blood and urine can be used as biomarkers and become an important diagnostic indicator for DON poisoning monitoring. This study aimed to reveal the differences in DON-induced metabolites in the serum and urine of weaned rabbits. Thirty-two weaned rabbits were divided into two groups: control group and DON group. Both groups of rabbits were fed a basic diet. Rabbits in the DON group were administered 1.5 mg/kg b.w. DON by intraperitoneal injection on an empty stomach in the morning every two days. Rabbits in the control group were injected with the same amount of saline every two days in the same way. After the 25-day trial, serum and urine samples from different experimental periods were collected. The results based on the LC-MS/MS method showed that DON can be metabolized rapidly in blood, and urine is the main metabolic pathway for DON. Data based on metabolomics illustrated that underlying biomarkers in serum were mainly involved in glycerophospholipid metabolism, tryptophan metabolism and pentose and glucuronate interconversions, while those in urine samples were involved in caffeine metabolism, glycine, serine and threonine metabolism, and terpenoid backbone biosynthesis. Correlation analysis suggested that DON can induce changes in certain disease-related metabolites in serum and urine. In conclusion, the pathogenic mechanism of DON includes multiple levels, indicating that DON poisoning is caused by multiple factors acting on multiple links.

Bacillus amyloliquefaciens B10 inhibits aflatoxin B1-induced cecal inflammation in mice by regulating their intestinal flora

Aflatoxin B1 is a mycotoxin that widely exists in feed and has a great impact on human and animal health. This study aimed to examine whether Bacillus amyloliquefaciens B10 protected against aflatoxin B1-induced cecal inflammation in mice. It was found that Bacillus amyloliquefaciens B10 could significantly improve the effects of AFB1 on body weight and intestinal inflammation of mice and enhance the expression of tight-junction protein. Compared with the CON group, the combination of AFB1 and B10 significantly increased the abundance of Actinobacteria and Bacilli in a collaborative manner, and significantly reduced the abundance of Ruminococcae, Lactobacillaceae and Clostridia. Meanwhile, the results showed that the abundance of Bacterides and Bacterdia in AFB1 + B10 group was significantly lower than that of AFB1 group, and the Firmicutes increased significantly. Bacillus amyloliquefaciens B10 can be used as a feed additive and alleviate cecal inflammation induced by AFB1 in mice by regulating intestinal flora.

Mechanism of deoxynivalenol mediated gastrointestinal toxicity: Insights from mitochondrial dysfunction

Deoxynivalenol (DON) is a mycotoxin predominantly produced by Fusarium genus, and widely contaminates cereals and associated products all over the world. The intestinal toxicity of DON is well established. However, intestinal homeostasis involves mitochondria, which has rarely been considered in the context of DON exposure. We summarize the recent knowledge on mitochondria as a key player in maintaining intestinal homeostasis based on their functions in cellular energy metabolism, redox homeostasis, apoptosis, intestinal immune responses, and orchestrated bidirectional cross-talk with gut microbe. In addition, we discuss the pivotal roles of mitochondrial dysfunction in the intestinal toxicity of DON and highlight promising mitochondrial-targeted therapeutics for DON-induced intestinal injury. Recent studies support that the intestinal toxicity of DON is attributed to mitochondrial dysfunction as a critical factor. Mitochondrial dysfunction characterized by failure in respiratory capacities and ROS overproduction has been demonstrated in intestinal cells exposed to DON. Perturbation of mitochondrial respiration leading to ROS accumulation is implicated in the early initiation of apoptosis. DON-induced intestinal inflammatory response is tightly linked to the mitochondrial ROS, whereas immunosuppression is intimately associated with mitophagy inhibition. DON perturbs the orchestrated bidirectional cross-talk between gut microbe and host mitochondria, which may be involved in DON-induced intestinal toxicity.

Effect of Clostridium on proliferating cell nuclear antigen and ghrelin in the small intestine of fattening pigs fed with deoxynivalenol

Grains and feed are severely contaminated by deoxynivalenol (DON) globally, threatening both human and animal health. Research on bio-degradation of DON, in general, is gaining attention. The aim of this research was to estimate the effect of Clostridium sp. WJ06 as a microbiological detoxification of DON based on the expression and distribution of proliferating cell nuclear antigen (PCNA) as well as ghrelin in the small intestine. A total of 24 fattening pigs were randomly divided into three groups. The control group was fed with a basic diet, the DON group was fed with DON at 5.0 mg/kg in feed, and the DON+C group was provided DON feed with Clostridium sp. WJ06. Several selected blood parameters, the intestinal morphology, and the expression and distribution of PCNA and ghrelin, were evaluated. The results proved that the selected blood parameters were altered, the intestinal villi were damaged, the epithelium was shed, as well as the expression and distribution of PCNA and ghrelin were changed by DON exposure. These toxic effects were prevented by the addition of Clostridium sp. WJ06. In short, the addition of Clostridium sp. WJ06 to the feed may eliminate the toxic effects of DON in fattening pigs. An underlying mechanism is likely modulation of the expression and distribution of PCNA and ghrelin.

Study on the interactive effect of deoxynivalenol and Clostridium perfringens on the jejunal health of broiler chickens

With global warming and ban on antibiotics, it occurs occasionally that deoxynivalenol (DON) together with Clostridium perfringens impairs the gut health of broiler chickens. However, the interactive effect of DON and C. perfringens on intestinal health is still unknown. A total of 120 one-day-old Arbor Acres broilers were randomly distributed to 4 groups. Birds were gavaged with C. perfringens (8 × 10⁸ CFU/d per bird) or sterile medium and fed a DON diet (0 or 5 mg of DON per kg diet) to investigate the interactive effects. The main effect analysis showed that DON diet significantly downregulated (P < 0.05) the mRNA expression of mucin-2, B-cell lymphoma-2–associated X, and cysteinyl aspartate–specific proteinase-3 of jejunal mucosa; decreased (P < 0.05) the indexes of ACE, Chao1, Shannon, and Simpson; and also decreased the relative abundance of the phylum Bacteroidete and the genera Lactococcus in jejunal contents of broilers chickens. Meanwhile, C. perfringens significantly increased (P < 0.05) crypt depth; decreased (P < 0.05) the ratio of villi height to crypt depth, the activity of jejunal diamine oxidase, and the relative abundance of Lactococcus; and upregulated (P < 0.05) the relative expression of B-cell lymphoma-2 and cysteinyl aspartate–specific proteinase-8. Furthermore, the interactions between DON and C. perfringens were most significant (P < 0.05) in the mRNA expression of lipopolysaccharide-induced TNF factor (LITAF) and TLR-4, the abundance of the genera Lactococcus in jejunal contents, and butyric acid concentrations in cecal contents of birds. Finally, Spearman correlation analysis suggested that the most negative correlations (P < 0.05) with the abundance of the genera except Lactobacillus were observed within the mRNA expression of LITAF. The abundance of Lactococcus had a positive correlation (P < 0.05) with the expression of Caspase-3. Most genera except Lactobacillus negatively correlated (P < 0.05) with acetic acid, butyric acid, and total short-chain fatty acids. In conclusion, dietary deoxynivalenol and C. perfringens challenge had a harmful effect on the jejunal health and should be carefully monitored in broiler production.

The Effects of Deoxynivalenol on the Ultrastructure of the Sacculus Rotundus and Vermiform Appendix, as Well as the Intestinal Microbiota of Weaned Rabbits

Deoxynivalenol (DON) is a mycotoxin found in grains that poses a potential threat to human and animal health, and the gastrointestinal tract is the primary target organ. There are few studies focused on the toxicology of DON to rabbits, especially on the relation among DON, microbiota, and the gut-associated lymphoid tissue. A total of 30 weaned rabbits (35 d) were evenly divided into the control group and DON group (1.5 mg/kg bodyweight (BW)) based on their body weight. After a 24-day trial, the ultrastructures of the sacculus rotundus and vermiform appendix were observed using a scanning electron microscope and transmission electron microscopy. The morphology and microflora in the ileum, caecum, and colon were also examined. The results proved that the ultrastructure of the sacculus rotundus and vermiform appendix, as well as the integrity of the intestinal barrier (especially for the ileum), were impaired after DON was administrated to the rabbits. Compared to the control group, the relative abundance and diversity of the microflora decreased in all three intestinal segments in the DON group, particularly in the ileum and caecum. In conclusion, the toxic effect of DON on weaned rabbits may be performed by destroying the structure of the sacculus rotundus and vermiform appendix, as well as affecting the structure and diversity of the intestinal flora.

Novel Soil Bacterium Strain Desulfitobacterium sp. PGC-3-9 Detoxifies Trichothecene Mycotoxins in Wheat via De-Epoxidation under Aerobic and Anaerobic Conditions

Trichothecenes are the most common mycotoxins contaminating small grain cereals worldwide. The C12,13 epoxide group in the trichothecenes was identified as a toxic group posing harm to humans, farm animals, and plants. Aerobic biological de-epoxidation is considered the ideal method of controlling these types of mycotoxins. In this study, we isolated a novel trichothecene mycotoxin-de-epoxidating bacterium, Desulfitobacterium sp. PGC-3-9, from a consortium obtained from the soil of a wheat field known for the occurrence of frequent Fusarium head blight epidemics under aerobic conditions. Along with MMYPF media, a combination of two antibiotics (sulfadiazine and trimethoprim) substantially increased the relative abundance of Desulfitobacterium species from 1.55% (aerobic) to 29.11% (aerobic) and 28.63% (anaerobic). A single colony purified strain, PGC-3-9, was isolated and a 16S rRNA sequencing analysis determined that it was Desulfitobacterium. The PGC-3-9 strain completely de-epoxidated HT-2, deoxynivalenol (DON), nivalenol and 15-acetyl deoxynivalenol, and efficiently eliminated DON in wheat grains under aerobic and anaerobic conditions. The strain PGC-3-9 exhibited high DON de-epoxidation activity at a wide range of pH (6–10) and temperature (15–50 °C) values under both conditions. This strain may be used for the development of detoxification agents in the agriculture and feed industries and the isolation of de-epoxidation enzymes.

Effect of commercially purified deoxynivalenol and zearalenone mycotoxins on microbial diversity of pig cecum contents

OBJECTIVE

Deoxynivalenol (DON) and zearalenone (ZEN) are mycotoxins that frequently contaminate maize and grain cereals, imposing risks to the health of both humans and animals and leading to economic losses. The gut microbiome has been shown to help combat the effects of such toxins, with certain microorganisms reported to contribute significantly to the detoxification process.

METHODS

We examined the cecum contents of three different dietary groups of pigs (control, as well as diets contaminated with 8 mg DON/kg feed or 0.8 mg ZEN/kg feed). Bacterial 16S rRNA gene amplicons were acquired from the cecum contents and evaluated by next-generation sequencing.

RESULTS

A total of 2,539,288 sequences were generated with ~500 nucleotide read lengths. Firmicutes, Bacteroidetes, and Proteobacteria were the dominant phyla, occupying more than 96% of all three groups. Lactobacillus, Bacteroides, Megasphaera, and Campylobacter showed potential as biomarkers for each group. Particularly, Lactobacillus and Bacteroides were more abundant in the DON and ZEN groups than in the control. Additionally, 52,414 operational taxonomic units were detected in the three groups; those of Bacteroides, Lactobacillus, Campylobacter, and Prevotella were most dominant and significantly varied between groups. Hence, contamination of feed by DON and ZEN affected the cecum microbiota, while Lactobacillus and Bacteroides were highly abundant and positively influenced the host physiology.

CONCLUSION

Lactobacillus and Bacteroides play key roles in the process of detoxification and improving the immune response. We, therefore, believe that these results may be useful for determining whether disturbances in the intestinal microflora, such as the toxic effects of DON and ZEN, can be treated by modulating the intestinal bacterial flora.

Isolation and Characterization of a Deoxynivalenol-Degrading Bacterium Bacillus licheniformis YB9 with the Capability of Modulating Intestinal Microbial Flora of Mice

Deoxynivalenol (DON) is one of the most prevalent food- and feed-associated mycotoxins. It frequently contaminates agricultural commodities and poses serious threats to human and animal health and leads to tremendous economic losses globally. Much attention has been paid to using microorganisms to detoxify DON. In this study, a Bacillus licheniformis strain named YB9 with a strong ability to detoxify DON was isolated and characterized from a moldy soil sample. YB9 could degrade more than 82.67% of 1 mg/L DON within 48 h at 37 °C and showed strong survival and DON degradation rate at simulated gastric fluid. The effects of YB9 on mice with DON intragastrical administration were further investigated by biochemical and histopathological examination and the gut microbiota was analyzed by 16S rRNA Illumina sequencing technology. The results showed that DON increased the levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and creatinine (Cr), decreased those of immunoglobulin G (IgG) and IgM in serum, and resulted in severe pathological damage of the liver, kidney, and spleen. By contrast, YB9 supplementation obviously inhibited or attenuated the damages caused by DON in mice. In addition, YB9 addition repaired the DON-induced dysbiosis of intestinal flora, characterized by recovering the balance of Firmicutes and Bacteroidetes to the normal level and decreasing the abundance of the potentially harmful bacterium Turicibacter and the excessive Lactobacillus caused by DON. Taken together, DON-degrading strain YB9 might be used as potential probiotic additive for improving food and feed safety and modulating the intestinal microbial flora of humans and animals.

Dual Function of a Novel Bacterium, Slackia sp. D-G6: Detoxifying Deoxynivalenol and Producing the Natural Estrogen Analogue, Equol

Deoxynivalenol (DON) is a highly abundant mycotoxin that exerts many adverse effects on humans and animals. Much effort has been made to control DON in the past, and bio-transformation has emerged as the most promising method. However, useful and effective application of bacterial bio-transformation for the purpose of inhibiting DON remains urgently needed. The current study isolated a novel DON detoxifying bacterium, Slackia sp. D-G6 (D-G6), from chicken intestines. D-G6 is a Gram-positive, non-sporulating bacterium, which ranges in size from 0.2–0.4 μm × 0.6–1.0 μm. D-G6 de-epoxidizes DON into a non-toxic form called DOM-1. Optimum conditions required for degradation of DON are 37–47 °C and a pH of 6–10 in WCA medium containing 50% chicken intestinal extract. Besides DON detoxification, D-G6 also produces equol (EQL) from daidzein (DZN), which shows high estrogenic activity, and prevents estrogen-dependent and age-related diseases effectively. Furthermore, the genome of D-G6 was sequenced and characterized. Thirteen genes that show potential for DON de-epoxidation were identified via comparative genomics. In conclusion, a novel bacterium that exhibits the dual function of detoxifying DON and producing the beneficial natural estrogen analogue, EQL, was identified.

The Evaluation of the Antioxidant and Intestinal Protective Effects of Baicalin-Copper in Deoxynivalenol-Challenged Piglets

The present study was performed to evaluate the antioxidant and intestinal protective effects of baicalin-copper on deoxynivalenol-challenged piglets. Forty weaned piglets were randomly divided into four groups and assigned to different diets: (1) basal diet (Con), (2) 4 mg/kg deoxynivalenol of basal diet (DON), (3) 5 g/kg baicalin-copper of basal diet (BCU); and (4) 4 mg/kg deoxynivalenol + 5 g/kg baicalin‐copper of basal diet (DBCU). The results showed that the ADFI and ADG of piglets in the DON group were markedly lower than those in the Con group, but the ADFI and ADG of the DBCU group were not significantly different from those of the Con group. In piglets fed a DON-contaminated diet, dietary supplementation with BCU significantly decreased the mRNA levels of P70S6K, 4E-BP1, and HSP70 in the liver, the protein expression of HO-1 in the jejunum, and the expression of p-Nrf2 and p-NF-κB in the ileum but increased Mn-SOD activity in serum. Dietary supplementation with BCU increased jejunal maltase, ZIP4 and MT mRNA levels, and serum concentrations of Arg, Val, Ile, Leu, Lys, and Tyr in DON-contaminated piglets. In summary, BCU can alleviate the growth impairment induced by DON and enhance antioxidant capacity and nutrition absorption in piglets fed DON-contaminated diets.

The Effect of Low and High Dose Deoxynivalenol on Intestinal Morphology, Distribution, and Expression of Inflammatory Cytokines of Weaning Rabbits

Deoxynivalenol (DON) is a potential pathogenic factor to humans and animals, and intestinal tract is the primary target organ of DON. Data concerning the effects of DON on rabbits are scarce, especially for weaning rabbits. In this study, 45 weaning rabbits (35 d) were randomly and equally assigned into three groups. Group A was fed basic diet, while groups B and C were added DON at 0.5 mg/kg BW/d and 1.5 mg/kg BW/d, respectively, based on the basic diet. The experiment lasted for 24 days and the intestinal morphology, expression, and distribution of several cytokines in intestinal segments have been examined. The results indicated that ADG decreased while F/G increased significantly compared with the control group after DON added at 1.5 mg/kg BW/d. Some of the morphometric parameters (villi length, crypt depth, and goblet cells density) changed after DON was added. Meanwhile, the concentration as well as the expression levels of relative protein and mRNA of IL-1β, IL-2, IL-6, and IL-8 increased significantly. The immunohistochemistry results illustrated that the quantity and distribution of positive cells of inflammatory cytokines were changed after DON was added. In conclusion, the addition of DON damaged the intestinal morphology and changed the distribution and expression of inflammatory cytokines. The toxic effect depended on the dosage of DON.

Potential Link between Gut Microbiota and Deoxynivalenol-Induced Feed Refusal in Weaned Piglets

This study investigated the potential link between gut microbiota and deoxynivalenol (DON)-induced feed refusal. A total of 24 barrows were randomly divided into one of three diets containing 0.61 (control diet), 1.28, or 2.89 mg DON/kg feed for 28 days. Dietary exposure to DON at 2.89 mg/kg significantly decreased the relative abundances of unclassified_f_Lachnospiraceae, Phascolarctobacterium and Ruminococcaceae_UCG-014, whereas it increased Prevotella_9 and norank_f_Prevotellaceae in the cecal digesta. Moreover, the decreased relative abundance of unclassified_f_Lachnospiraceae induced by DON exposure was positively correlated with average daily feed intake. Exposure to DON increased the serum concentrations of glucagon-like peptide-1 and peptide YY but reduced the levels of serum growth hormone and insulin-like growth factor 1. In summary, these findings suggest that chronic dietary exposure to DON induces disturbances of intestinal microbiota. Disturbed appetite-regulating hormones and somatotropic-axis-hormone secretion induced by negative microbial changes could be the potential mechanisms for DON-induced anorexia.

Intestinal microbiome and its potential functions in bighead carp (Aristichthys nobilis) under different feeding strategies

Bighead carps (Aristichthys nobilis) were divided into four groups with different feeding strategies: group A, nature live food only (fertiliser only, 200 g urea + 160 g ethylamine phosphate + 250 g Huangjintai bio-fertiliser); group B, nature live food + 1/2 formulated feed; group C, nature live food + formulated feed; and group D, formulated feed only. The intestinal microbiomes of the different groups were compared through the Illumina MiSeq sequencing of the bacterial 16S rRNA gene. The specific growth rate (SGR), survival and blood biochemical factors of the fish were also investigated. Results showed that feeding treatment influenced the intestinal communities in the fish. In specific, more bacterial phyla dominated in groups A and B (phyla Bacteroidetes, Fusobacteria, Firmicutes and Proteobacteria in group A, phyla Proteobacteria and Fusobacteria in group B) than in groups C and D (phylum Proteobacteria). The diversity was also lower in groups C and D than in groups A and B. Unweighted pair-group method analysis revealed a clear difference in intestinal microbiota among the different feeding treatments. No difference in survival rate was found among the treatment groups, but the SGR was significantly higher (P < 0.01) in groups B, C and D than in group A. Functional analysis showed that the intestinal bacteria correlated with fish glucose metabolism in group A but with lipid metabolic activity in groups B, C and D. In summary, the intestinal microbiomes and their potential functions vary in bighead carp under different feeding treatments. This study provides new insights into the gut microbiomes of filter-feeding and formulated diet-fed fish.

Zearalenone Changes the Diversity and Composition of Caecum Microbiota in Weaned Rabbit

Mycotoxins exhibit several severe effects on intestinal health, but few studies have assessed mycotoxins effect on the intestinal microflora and its repercussions to humans and animals. In this study, we evaluated the effect of zearalenone (ZEA), one of the most harmful mycotoxins on the structure of caecal microbiota in rabbits. Twenty-eight male weaned rabbits were randomly divided into four groups and orally given different concentrations of ZEA (400, 800, and 1600 μg/kg.b.w). Microbial communities in caecum samples of rabbits were analyzed for 16S rRNA by Illumina sequencing through Illumina Miseq platform after being fed for 28 days. The results showed that increasing ZEA doses increased the species richness but did not significantly increased the species diversity of the caecum microbiota in the rabbits. In addition, the caecum microbiota from the samples in different ZEA-treated groups was clustered according to their dosing regimens. At the phylum level, ZEA decreased the abundance of Actinobacteria and significantly increased the abundance of Cyanobacteria, Synergistetes, and Proteobacteria. At the genus level, there were declines in the abundance of Adlercreutzia, Blautia, Desulfitobacter, Lactobacillus, Oxalobacter, and p-75-a5. The decrease of abundance in Lactobacillus, Desulfitobacter, and p-75-a5 was particularly noticeable. In conclusion, zearalenone could increase α-diversity but significantly decrease the abundance of some bacteria with the important metabolic functions. These findings suggested that ZEA could modify the caecum microbiota.

Colon Microbiome of Pigs Fed Diet Contaminated with Commercial Purified Deoxynivalenol and Zearalenone

Deoxynivalenol (DON) and zearalenone (ZEN) can seriously affect animal health, with potentially severe economic losses. Previous studies have demonstrated that gut microbiota plays a significant role in detoxification. We analyzed the colon contents from three groups of pigs (fed either a standard diet, or a diet with 8 mg/kg DON or ZEN). Bacterial 16S rRNA gene amplicons were obtained from the colon contents, and sequenced using next-generation sequencing on the MiSeq platform. Overall, 2,444,635 gene sequences were generated, with ≥2000 sequences examined. Firmicutes and Bacteroidetes were the dominant phyla in all three groups. The sequences of Lactobacillus, Megasphaera, and Faecalibacterium genera, and the unclassified Clostridiaceae family, represented more than 1.2% of the total, with significantly different abundances among the groups. Lactobacillus was especially more abundant in the DON (7.6%) and ZEN (2.7%) groups than in the control (0.2%). A total of 48,346 operational taxonomic units (OTUs) were identified in the three groups. Two OTUs, classified as Lactobacillus, were the most dominant in the DON and ZEN groups. The abundances of the remaining OTUs were also significantly different among the groups. Thus, the mycotoxin-contaminated feed significantly affected the colon microbiota, especially Lactobacillus, which was the most abundant. Therefore, we speculate that Lactobacillus plays a major role in detoxification of these mycotoxins.