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

Impact of concerning excipients on animal safety: insights for veterinary pharmacotherapy and regulatory considerations

OBJECTIVES

Veterinarians and pharmacists are familiar with the efficacy and safety aspects attributed to active pharmaceutical ingredients included in medicines, but they are rarely concerned with the safety of excipients present in medicines. Although generally recognized as safe, excipients are not chemically inert and may produce adverse events in certain animal populations. This review aims to present excipients of concern to these populations and highlight their relevance for rational veterinary pharmacotherapy.

EVIDENCE ACQUISITION

A comprehensive review of the literature about the existence of adverse reactions in animals caused by pharmaceutical excipients was carried out based on an exploratory study. An overview of the correct conditions of use and safety of these excipients has also been provided, with information about their function, the proportion in which they are included in the different pharmaceutical dosage forms and the usual routes of administration.

RESULTS

We identified 18 excipients considered of concern due to their potential to cause harm to the health of specific animal populations: bentonite, benzalkonium chloride, benzoic acid, benzyl alcohol, ethanol, lactose, mannitol, mineral oil, monosodium glutamate, polyethylene glycol, polysorbate, propylene glycol, sodium benzoate, sodium carboxymethylcellulose, sodium lauryl sulfate, sulfites, polyoxyethylene castor oil derivatives, and xylitol. Among the 135 manuscripts listed, only 24 referred to studies in which the substances were correctly evaluated as excipients.

CONCLUSIONS

Based on the information presented in this review, the authors hope to draw the attention of professionals involved in veterinary pharmacotherapy to the existence of excipients of concern in medicines. This information contributes to rational veterinary pharmacotherapy and supports veterinary pharmacovigilance actions. We hope to shed light on the subject and encourage studies and new manuscripts that address the safety of pharmaceutical excipients to the animal population.

In-vivo evaluation of the adverse effects of ochratoxin A on broiler chicken health and adsorption efficacy of indigenous and commercial clay of Balochistan, Pakistan

Mycotoxins in animal feed pose health risks and economic losses, but using various adsorbent types could potentially protect animals from mycotoxicosis. The study aimed to assess the effect of OTA on the health of broiler chickens and to envisage the ameliorative potential of clay adsorbents. The objectives of this in vivo study were to investigate the effects of OTA on productivity, biochemical parameters, fecal residues, and the preventive effects of indigenous and commercial clay of Balochistan as adsorbents to alleviate the adverse effects of exposure. Male broiler chickens (n = 160) were treated with 400 μg/kg OTA and 0.5 g/kg clay adsorbent for 42 days, with feed and water available in an ad libitum manner. The amount of OTA in diet and fecal residues was assessed through HPLC. The administration of OTA in the diet, resulted in a significant (p < 0.05) decrease in the average daily gain (ADG) and average daily feed intake (ADFI) while increasing the feed conversion ratio (FCR) as compared to the control group. Furthermore, no significant (p > 0.05) differences were found between the weight gain of broiler chickens fed without OTA (positive control) and that of chickens fed adsorbent. The group given a diet containing OTA without adsorbents as compared to the control and adsorbent-supplemented group has shown a significant (p < 0.05) increase in the relative weight of the liver, kidney, gizzard, and proventriculus while decreasing the relative weight of the spleen and bursa of Fabricius. Alterations in the levels of serum total protein (TP), cholesterol (CHL), serum urea (SU), enzymatic activity (aspartate aminotransferase (AST) and alanine transaminase (ALT)), and creatinine were observed in the OTA-intoxicated and adsorbent-supplemented groups as compared to the control group. Adsorbent supplementation resulted in a significantly (p < 0.05) higher OTA content in the faeces. It can be concluded from the results of this study, that OTA intoxication negatively affects the health of broiler chickens, and the clay of Balochistan has shown effective adsorption potential against OTA.

The effects of probiotic-based additives on aflatoxin intoxication in Piaractus mesopotamicus: a study of liver histology and metabolic performance

Mycotoxins, produced by fungi, can contaminate fish food and harm their health. Probiotics enhance immune balance and primarily function in the animal intestine. This study aimed to assess aflatoxin's impact on Piaractus mesopotamicus and explore probiotic-based additive (PBA) benefits in mitigating these effects, focusing on antioxidant activity, biochemical indices, and hepatic histopathology. Two experiments were conducted using P. mesopotamicus fry. The first experimental assay tested various levels of aflatoxin B1 (0.0, 25.0, 50.0, 100.0, 200.0, and 400.0 µg kg-1) over a 10-day period. The second experimental assay examined the efficacy of the probiotic (supplemented at 0.20%) in diets with different levels of aflatoxin B1 (0.0, 25.0, and 400.0 µg kg-1) for 15 days. At the end of each assay, the fish underwent a 24-hour fasting period, and the survival rate was recorded. Six liver specimens from each treatment group were randomly selected for metabolic indicator assays, including superoxide dismutase, catalase, alanine aminotransferase, aspartate aminotransferase, and albumin. Additionally, histopathological analysis was performed on six specimens. The initial study discovered that inclusion rates above 25.0 µg kg-1 resulted in decreased activity of AST (aspartate aminotransferase), ALT (alanine aminotransferase), ALB (albumin), CAT (catalase), and SOD (superoxide dismutase), accompanied by liver histopathological lesions. In the second study, the inclusion of PBA in diets contaminated with AFB1 improved the activity of AST and ALT up to 25.0 µg kg-1 of AFB1, with no histopathological lesions observed. The study demonstrated the hepatoprotective effects of PBA in diets contaminated with AFB1. The enzyme activity and hepatic histopathology were maintained, indicating a reduction in damage caused by high concentrations of AFB1 (400.0 µg kg-1 of AFB1). The adverse effects of AFB1 on biochemical and histopathological parameters were observed from 25.0 µg kg-1 onwards. Notably, PBA supplementation enhanced enzymatic activity at a concentration of 25 µg kg-1 of AFB1 and mitigated the effects at 400.0 µg kg-1 of AFB1. The use of PBAs in pacu diets is highly recommended as they effectively neutralize the toxic effects of AFB1 when added to diets containing 25.0 µg kg-1 AFB1. Dietary inclusion of aflatoxin B1 at a concentration of 25.0 µg kg-1 adversely affects the liver of Piaractus mesopotamicus (Pacu). However, the addition of a probiotic-based additive (PBA) to the diets containing this concentration of aflatoxin neutralized its toxic effects. Therefore, the study recommends the use of PBAs in Pacu diets to mitigate the adverse effects of aflatoxin contamination.

Seasonal variation of mycotoxin levels in poultry feeds and feed ingredients in Oyo State, Nigeria

Mycotoxins pose a major problem to poultry production as a result of feed contamination which has deleterious consequences such as production losses and human health risks. A total of 158 chicken feed samples were randomly collected from 46 consenting poultry farms in Oyo State throughout the wet season (April-October; 91 samples) and the dry season (November-March; 67 samples), including compounded feed (n = 129) and feed ingredients (n = 29). Samples were promptly transported to the laboratory in sterile plastic vials for lateral flow assay for mycotoxins using six different commercial mycotoxin test kits each for aflatoxin B1, zearalenone, deoxynivalenol, ochratoxin A, fumonisin, and T-2 toxin/HT-2 toxin. Summary values of mycotoxin levels (µg/kg) in the feedstuffs were represented as frequency or median (and range). Fisher exact or Mann-Whitney U tests were carried out where appropriate at α = 0.05. Every sample contained at least four mycotoxins. Aflatoxins and fumonisin co-occurred in 80% of the samples. Aflatoxin and fumonisin concentrations were above the permissible limits in 32.9% and 18.4% respectively in feedstuff sampled in the dry season while the values were 17.1% and 6.3% respectively during the wet season. Among feed ingredients, peanut cake and maize had the highest median concentration of aflatoxin and fumonisin, respectively. Median aflatoxin concentration in the feedstuff was significantly higher than the permissible limit irrespective of season. There is a need to frequently monitor mycotoxin levels of feed and feed ingredients and improve storage system for feed ingredients in order to reduce the risk associated with high mycotoxin intake in poultry.

Emerging insights into the impacts of heavy metals exposure on health, reproductive and productive performance of livestock

Heavy metals, common environmental pollutants with widespread distribution hazards and several health problems linked to them are distinguished from other toxic compounds by their bioaccumulation in living organisms. They pollute the food chain and threaten the health of animals. Biologically, heavy metals exhibit both beneficial and harmful effects. Certain essential heavy metals such as Co, Mn, Se, Zn, and Mg play crucial roles in vital physiological processes in trace amounts, while others like As, Pb, Hg, Cd, and Cu are widely recognized for their toxic properties. Regardless of their physiological functions, an excess intake of all heavy metals beyond the tolerance limit can lead to toxicity. Animals face exposure to heavy metals through contaminated feed and water, primarily as a result of anthropogenic environmental pollution. After ingestion heavy metals persist in the body for an extended duration and the nature of exposure dictates whether they induce acute or chronic, clinical or subclinical, or subtle toxicities. The toxic effects of metals lead to disruption of cellular homeostasis through the generation of free radicals that develop oxidative stress. In cases of acute heavy metal poisoning, characteristic clinical symptoms may arise, potentially culminating in the death of animals with corresponding necropsy findings. Chronic toxicities manifest as a decline in overall body condition scoring and a decrease in the production potential of animals. Elevated heavy metal levels in consumable animal products raise public health concerns. Timely diagnosis, targeted antidotes, and management strategies can significantly mitigate heavy metal impact on livestock health, productivity, and reproductive performance.

Optimization and in-house validation of the analytical procedure for official control of bentonites as aflatoxin inactivators

In Europe, bentonites are allowed as feed additives for aflatoxin mitigation (1m558) provided they have specific mineralogical characteristics and an aflatoxin-binding capacity (BCAfB1) above 90%. BCAfB1 is determined by an official adsorption assay using an aflatoxin solution (4 mg/L) in acetate buffer (pH 5.0) and a bentonite at 0.02% (w/v). To date, the robustness of this method has not been investigated. In this work, we addressed this challenge and performed a robustness study by analyzing six bentonite samples that met the mineralogical requirements for claim code 1 m558. Leading factors selected for robustness testing were (1) preparation mode of bentonite suspension, (2) residual amount of acetonitrile in the test trial, (3) acetate buffer concentration, (4) incubation time, and (5) centrifugation. It was statistically evinced that factors 2 and 5 affected the results. Due to its weakness, the method excluded 4 out of six bentonites to be marketed in EU, being BCAfB1 < 90%. A new protocol was developed by keeping the main experimental parameters of the official assay and was in-house validated. This protocol yielded BCAfB1 > 90% for all test bentonites and showed satisfactory precisions with a RSDI of 3.4% and HorRat < 2. Its validity was proven by the isotherm approach, comparing Langmuir adsorption parameters with BCAfB1 values. Application of the protocol to bentonites other than montmorillonite was demonstrated.

Ameliorative effects of Sida acuta and vitamin C on serum DNA damage, pro-inflammatory and anti-inflammatory cytokines in roosters fed aflatoxin B1 contaminated diets

The ameliorative effects of Sida acuta leaf meal (SALM) and vitamin C on the serum pro-inflammatory and anti-inflammatory cytokines as well as DNA damage of cocks fed aflatoxin B1 (AFB1) contaminated diets were examined. The experiment was a completely randomized design with a total of 250 sexually mature Isa White cocks aged 24 weeks, randomly allotted into five experimental diets; each diet contained 5 replicates with 10 roosters. The diets were A (control/basal diet), B (A + 1 mg/kg AFB1), C (B + 200 mg/kg vitamin C), D (B + 2.5 g/kg SALM) and E (B + 5.0 g/kg SALM). Fresh and clean water was also provided for the whole experimental period of twelve weeks. Inclusion of 1 mg/kg AFB1 without vitamin C or SALM increased TNF-α and IL-1β as well as 8-OHdG and NF-κB in the serum significantly (P < 0.05) among the cocks on diet B. However, the fortification of AFB1 contaminated diets with vitamin C and SALM depressed serum TNF-α, IL-1β, 8-OHdG and NF-κB concentrations of the cocks significantly (P < 0.05). Conversely, serum IL-4 and IL-10 in birds given 1 mg/kg AFB1 without vitamin C or SALM decreased significantly (P < 0.05) in comparison with the roosters on the control. However, improvements (P < 0.05) in IL-4 and IL-10 concentrations with corresponding reduction (P < 0.05) in TNF-α, IL-1β, 8-OHdG and NF-κB concentrations were recorded among cocks fed Diets C, D and E, respectively. Therefore, dietary addition of SALM at the level used in this study was beneficial and has comparable effects with inorganic antioxidant (C vitamin) by significantly reducing the inflammatory cytokines and oxidative damage biomarkers as well as enhancing the anti-inflammatory cytokines thereby promoting the health status of the cocks fed AFB1 contaminated ration.

Effects of Combinations of Toxin Binders with or without Natural Components on Broiler Breeders Exposed to Ochratoxin A

The objective of this study was to investigate the effects of toxin binders on broiler breeders fed an ochratoxin A (OTA)-contaminated diet. A total of 60 45-week-old female Arbor Acres broiler breeder birds with an initial body weight of 3.65 ± 0.35 kg were randomly divided into 6 treatment groups, with 10 replicates per group and 1 bird per replicate. The trial was conducted for 9 weeks (including 1 week of adaptation). Feed additive 1 (FA1) was composed of clay minerals (85% bentonite and 12% clinoptilolite) with 3% charcoal. FA2 was composed of clay minerals (66.1% aluminosilicates) with natural components (0.8% artichoke and rosemary plant extracts), 7% yeast extract, 0.5% beta-glucans, and 25.6% carriers. The dietary treatment groups were as follows: (1) birds fed an OTA-free basal diet (Negative Control; NC); (2) lipopolysaccharide (LPS)-challenged birds fed a diet including OTA (4 mg/kg) (Positive Control, PC); (3) the PC with 0.05% FA1 (Treatment 1, T1); (4) the PC with 0.10% FA1 (Treatment 2, T2); (5) the PC with 0.10% FA2 (Treatment 3, T3); and (6) the PC with 0.20% FA2 (Treatment 4, T4). The LPS challenge (an intramuscular injection of 1 mg E. coli O55:B5 LPS per kg of body weight) was performed on the first day of the experiment. The results of this experiment show that the PC treatment negatively affected (p < 0.05) egg production, hatchability, Haugh unit, bone mineralization, relative organ weight (abdominal fat, liver), the levels of glutamic oxaloacetic transaminase (GOT), high-density lipoprotein (HDL), and total cholesterol in the blood, and OTA accumulation in the liver compared with the NC. However, supplementation with toxin binders mitigated (p < 0.05) the negative effects of the OTA. Specifically, supplementation with 0.10% FA1 and 0.10% FA2 increased (p < 0.05) eggshell strength by week 4, and the Haugh unit and bone mineralization (phosphorous) by week 8, while decreasing (p < 0.05) the relative weight of the liver and the levels of GOT and HDL in the blood. Supplementation with 0.10% FA2 led to greater improvements in various parameters, including laying performance and bone mineralization, than the other treatments. In conclusion, toxin binders with or without natural components can be effective tools in the mitigation of OTA-induced problems due to their synergistic effects.

Removal of Aflatoxin B1 and Zearalenone in Mixed Aqueous Solution by Palygorskite-Montmorillonite Materials In Situ Prepared from Palygorskite Mineral

In view of the animal feeds inevitably contaminated by multiple mycotoxins, eco-friendly and efficient palygorskite-montmorillonite (Pal-Mt) materials were prepared to remove polar aflatoxin B₁ (AFB₁) and weak polar zearalenone (ZEN) from mixed mycotoxins aqueous solution. The adsorption properties and bonding mechanisms between Pal-Mt materials and mycotoxins (AFB₁ and ZEN) were investigated systematically. The as-prepared Pal-Mt showed excellent adsorption capacity for AFB₁ and ZEN in single- and binary-mycotoxin systems, indicating the effectiveness of Pal-Mt acting as multiple mycotoxin adsorbents. The kinetics of adsorption for ZEN was fast due to the adsorption on the external surface (film and intraparticle diffusion), while AFB₁ molecules permeated into mesopores after the external adsorption for the more planar structure. Adsorption isotherms demonstrated that heterogeneous surface adsorption appeared between Pal-Mt and AFB₁, and monolayer adsorption occurred on Pal-Mt and ZEN for different polarities of mycotoxins. Thermodynamic parameters illustrated that the adsorption process of both AFB₁ and ZEN onto Pal-Mt was spontaneous and endothermic. The adsorption mechanism studies suggested that hydrogen bonding, electrostatic attraction, calcium bridging linkage, and ion-dipole played fundamental roles in the interaction between Pal-Mt and these two mycotoxins.

Enzymatic Degradation of Zearalenone in the Gastrointestinal Tract of Pigs, Chickens, and Rainbow Trout

The estrogenic mycotoxin zearalenone (ZEN) is a common contaminant of animal feed. Effective strategies for the inactivation of ZEN in feed are required. The ZEN-degrading enzyme zearalenone hydrolase ZenA (EC 3.1.1.-, commercial name ZENzyme^®, BIOMIN Holding GmbH, Getzersdorf, Austria) converts ZEN to hydrolyzed ZEN (HZEN), thereby enabling a strong reduction in estrogenicity. In this study, we investigated the efficacy of ZenA added to feed to degrade ZEN in the gastrointestinal tract of three monogastric animal species, i.e., pigs, chickens, and rainbow trout. For each species, groups of animals received (i) feed contaminated with ZEN (chickens: 400 µg/kg, pigs: 200 µg/kg, rainbow trout: 2000 µg/kg), (ii) feed contaminated with ZEN and supplemented with ZenA, or (iii) uncontaminated feed. To investigate the fate of dietary ZEN in the gastrointestinal tract in the presence and absence of ZenA, concentrations of ZEN and ZEN metabolites were analyzed in digesta of chickens and rainbow trout and in feces of pigs. Upon ZenA administration, concentrations of ZEN were significantly decreased and concentrations of the degradation product HZEN were significantly increased in digesta/feces of each investigated animal species, indicating degradation of ZEN by ZenA in the gastrointestinal tract. Moreover, upon addition of ZenA to the diet, the concentration of the highly estrogenic ZEN metabolite α-ZEL was significantly reduced in feces of pigs. In conclusion, ZenA was effective in degrading ZEN to HZEN in the gastrointestinal tract of chickens, pigs, and rainbow trout, and counteracted formation of α-ZEL in pigs. Therefore, ZenA could find application as a ZEN-degrading feed additive for these animal species.

The Efficacy of Additives for the Mitigation of Aflatoxins in Animal Feed: A Systematic Review and Network Meta-Analysis

The contamination of animal feed with aflatoxins is an ongoing and growing serious issue, particularly for livestock farmers in tropical and subtropical regions. Exposure of animals to an aflatoxin-contaminated diet impairs feed efficiency and increases susceptibility to diseases, resulting in mortality, feed waste, and increased production costs. They can also be excreted in milk and thus pose a significant human health risk. This systematic review and network meta-analysis aim to compare and identify the most effective intervention to alleviate the negative impact of aflatoxins on the important livestock sector, poultry production. Eligible studies on the efficacy of feed additives to mitigate the toxic effect of aflatoxins in poultry were retrieved from different databases. Additives were classified into three categories based on their mode of action and composition: organic binder, inorganic binder, and antioxidant. Moreover, alanine transaminase (ALT), a liver enzyme, was the primary indicator. Supplementing aflatoxin-contaminated feeds with different categories of additives significantly reduces serum ALT levels (p < 0.001) compared with birds fed only a contaminated diet. Inorganic binder (P-score 0.8615) was ranked to be the most efficient in terms of counteracting the toxic effect of aflatoxins, followed by antioxidant (P-score 0.6159) and organic binder (P-score 0.5018). These findings will have significant importance for farmers, veterinarians, and animal nutrition companies when deciding which type of additives to use for mitigating exposure to aflatoxins, thus improving food security and the livelihoods of smallholder farmers in developing countries.

A porous ceramic particle with or without a preservative blend did not impair apparent digestibility of macro- and micro-nutrients of postweaned pigs

The objective of this study was to determine the effects of supplementing a commercial porous ceramic clay particle, with or without a blend of preservatives, on the performance and nutrient digestibility of weanling pigs. Fifteen weanling pigs of the Yorkshire, Landrace, and Duroc breeds were blocked by breed and randomly assigned to one of three treatments (n = 5): (1) Control, non-medicated diet with no additional feed additives (CON); (2) PowerGuard, basal diet with 0.25% of the DM consisting of a ceramic particle mixed into the pelleted feed (PG; MB Nutritional Sciences, Lubbock, TX, 79403); or (3) Power Guard + a blend of preservatives, basal diet with 0.3% of the DM consisting of the ceramic clay and preservatives mixed into the pelleted feed (PG-D). The facility was temperature controlled with an average temperature of 28.5 °C. Pigs were offered ad libitum access to feed and water and were housed individually in elevated crates. Body weights were collected upon enrollment on day 0 and at the end of the observation period on day 18. On day 15 , a 72-h total feed and fecal collection period began. Feed and fecal samples were analyzed for DM, CP, Ash, OM, ADF, NDF, zinc, copper, thiamin (vitamin B1), and retinol (vitamin A). Liver samples were collected immediately after harvest and frozen for later mineral analysis. Data were analyzed using Proc Mixed in SAS with dietary group as the main effect and block as the random effect (SAS 9.4, Cary, NC). There were no treatment differences in performance measures including final BW, ADG, or G:F (P ≥ 0.701). There were no treatment differences in diet nutrient digestibility for DM, CP, Ash, OM, ADF, or NDF (P ≥ 0.312). Additionally, there were no treatment effects on zinc, copper, or retinol digestibility (P ≥ .298); however, thiamin inclusion rate was increased for the PG-D treatment, thus leading to an increased digestibility for thiamin (P = 0.018) in the PG-D treatment. There were no treatment differences in hepatic mineral concentrations (P ≥ 0.532); however, there was a tendency for pigs fed PG-D to have increased hepatic concentrations of lead and mercury when compared with both PG and CON pigs (P ≤ 0.066). In summary, supplementation of a commercial ceramic particle with or without a blend of preservatives to weaned pigs did not affect performance or apparent nutrient digestibility.

Does Bentonite Cause Cytotoxic and Whole-Transcriptomic Adverse Effects in Enterocytes When Used to Reduce Aflatoxin B1 Exposure?

Aflatoxin B1 (AFB1) is a major food safety concern, threatening the health of humans and animals. Bentonite (BEN) is an aluminosilicate clay used as a feed additive to reduce AFB1 presence in contaminated feedstuff. So far, few studies have characterized BEN toxicity and efficacy in vitro. In this study, cytotoxicity (WST-1 test), the effects on cell permeability (trans-epithelial electrical resistance and lucifer yellow dye incorporation), and transcriptional changes (RNA-seq) caused by BEN, AFB1 and their combination (AFB1 + BEN) were investigated in Caco-2 cells. Up to 0.1 mg/mL, BEN did not affect cell viability and permeability, but it reduced AFB1 cytotoxicity; however, at higher concentrations, BEN was cytotoxic. As to RNA-seq, 0.1 mg/mL BEN did not show effects on cell transcriptome, confirming that the interaction between BEN and AFB1 occurs in the medium. Data from AFB1 and AFB1 + BEN suggested AFB1 provoked most of the transcriptional changes, whereas BEN was preventive. The most interesting AFB1-targeted pathways for which BEN was effective were cell integrity, xenobiotic metabolism and transporters, basal metabolism, inflammation and immune response, p53 biological network, apoptosis and carcinogenesis. To our knowledge, this is the first study assessing the in vitro toxicity and whole-transcriptomic effects of BEN, alone or in the presence of AFB1.

A Dose-Response Investigation of a Micronized Porous Ceramic Particle to Improve the Health and Performance of Post-weaned Pigs Infected With Salmonella enterica Serotype Typhimurium

The objective was to investigate the effects of supplementing increasing concentrations of PowerGuard (PG), a micronized ceramic particle, to weaned pigs on health and performance following a Salmonella enterica serotype Typhimurium infection. Forty barrows were transported to the USDA facility in Liberty, TX, USA. Pigs were randomly assigned to one of five treatments (n = 8): (1) uninfected control (CON), no Salmonella typhimurium (ST) and no PG treatment; (2) infected control (ST), infected with ST but no PG treatment; (3) PG0.05, infected with ST and supplemented with 0.05% PG; (4) PG0.25, infected with ST and supplemented with 0.25% PG; and (5) PG0.50, infected with ST and supplemented with 0.5% PG. All pigs were enrolled at 21.5 ± 1.33 days of age and did not differ in initial BW (1.98 ± 0.09 kg). Pigs were anesthetized to insert temperature recording devices into the abdominal cavity. Pigs were offered feed and water ad libitum. Pigs in ST, PG0.05, PG0.25, and PG0.50 were infected orally with 1.75 × 107 colony-forming units of Salmonella typhimurium on day 7. Pig body weights and peripheral blood samples were collected on days 0, 7, 10, 14, and 21. Pigs were harvested on day 21 and ileum and liver samples were collected for histopathological analyses. There was no treatment difference for final BW (P ≥ 0.201). There was a tendency (P = 0.087) for a treatment difference in the fecal score; ST and PG0.50 had more loose fecal scores than CON and PG0.25. There was a treatment × time interaction for intraperitoneal temperature (P &lt; 0.0001); PG0.05, PG0.25, and PG0.50 had attenuated febrile responses during the acute post-infection period compared with ST. There was a treatment × time interaction for total leukocyte counts (P = 0.007); PG treatments reduced leukocytosis post-infection compared with ST. Supplementing PG0.25 improved many health and performance variables when pigs were infected with Salmonella Typhimurium. Furthermore, supplementing PG0.05 attenuated the febrile response and many hematological variables. However, supplementing PG0.5 did not improve many aspects of health or performance. Therefore, supplementing PowerGuard between 0.05 and 0.25% of the diet may play a role in protecting weaned pigs from disease caused by Salmonella.

In vitro mycotoxin binding capacities of clays, glucomannan and their combinations

Clays, glucomannans and their combinations are widely used to bind mycotoxins in contaminated feeds to reduce their toxic effects on animals. In the present study, the binding abilities of clinoptilolite, sepiolite, bentonite, and montmorillonite, glucomannan, and four commercial TB products (P1, P2, C1 and C2) were investigated in vitro for their binding effects on seven different mycotoxins (AF, aflatoxin; OTA, ochratoxin; ZEA, zearalenone; DON, deoxynivalenol; FUM, fumonisin; T-2 toxin, and HT-2 toxin) in medium at pH 3.0 and 6.8. The clays were observed to bind AF, DON, and OTA at the following levels: clinoptilolite on AF at 72-90%, on DON at 61-68%, and on OTA at 52-62%; sepiolite on AF at 92-98%, on DON at 36-68%, and on OTA at 53-55%; bentonite on AF at 88-95%, on DON at 23-73%, and on OTA at 54-56%, and montmorillonite on AF at 74-80%, on DON at 46-68%, and on OTA at 54-55%. We also observed that these clays bound ZEA, FUM, T-2, and HT-2 at 25-45%. Glucomannan bound AF at a high rate (85-96%); however, bound DON at 31-56% and OTA at 54-55%, and other mycotoxins at 25-43%. Although P1, which consisted of clay combinations, bound AF and OTA at high rates, it bound DON, FUM, ZEA, T-2, and HT-2 at medium rates. P2, to which glucomannan was added to the clay combination, was observed to have the ability to bind OTA, FUM, and T-2 at ∼15-20% more than P1. When similar commercial products were compared, P2 provided ∼>10% adsorption of AF, 20% of OTA and FUM, and 5% of T-2 than C1, while similar binding ability of these two products were observed on the other toxins.

Comprehensive Review on the Interactions of Clay Minerals With Animal Physiology and Production

Clay minerals are naturally occurring rock and soil materials primarily composed of fine-grained aluminosilicate minerals, characterized by high hygroscopicity. In animal production, clays are often mixed with feed and, due to their high binding capacity towards organic molecules, used to limit animal absorption of feed contaminants, such as mycotoxins and other toxicants. Binding capacity of clays is not specific and these minerals can form complexes with different compounds, such as nutrients and pharmaceuticals, thus possibly affecting the intestinal absorption of important substances. Indeed, clays cannot be considered a completely inert feed additive, as they can interfere with gastro-intestinal (GI) metabolism, with possible consequences on animal physiology. Moreover, clays may contain impurities, constituted of inorganic micronutrients and/or toxic trace elements, and their ingestion can affect animal health. Furthermore, clays may also have effects on the GI mucosa, possibly modifying nutrient digestibility and animal microbiome. Finally, clays may directly interact with GI cells and, depending on their mineral grain size, shape, superficial charge and hydrophilicity, can elicit an inflammatory response. As in the near future due to climate change the presence of mycotoxins in feedstuffs will probably become a major problem, the use of clays in feedstuff, given their physico-chemical properties, low cost, apparent low toxicity and eco-compatibility, is expected to increase. The present review focuses on the characteristics and properties of clays as feed additives, evidencing pros and cons. Aims of future studies are suggested, evidencing that, in particular, possible interferences of these minerals with animal microbiome, nutrient absorption and drug delivery should be assessed. Finally, the fate of clay particles during their transit within the GI system and their long-term administration/accumulation should be clarified.

Mycotoxin risk management for dairy cows by monitoring blood parameters, reproduction status and SCC in milk

ABSTRACT The objective of this study was to determine the effectiveness of mycotoxin management with feed additive by monitoring biochemical blood parameters, reproduction status and udder health in cows. During the first 1-12-months, the reproduction performance was assessed. The cows were fed only total mixed ration (TMR) with naturally contaminated mycotoxins (ZEN;DON;AFB1;OTA) and the cows were regarded as a control group (CG). In months 13-15, two groups were created: control (CG)(n=30) and experimental (EG)(n=60). The CG was fed with contaminated TMR and the EG was fed with the same TMR+40g/cow mycotoxins management feed additive (TMXL1000). During this period, blood indicators and udder health were studied. Beginning with months 16-24, all cows were fed with contaminated TMR+40 g/cow (TMXL1000) and regarded as the EG. The IgA concentrations in the CG decreased in the 15th month (p<0.05). The concentrations of cortisol decreased by two times (p<0.05) in the EG. Ovarian cyst treatment was more effective by 14.98% (p<0.05) in the EG than in the CG (p<0.05). The EG performed an effective (18.02%) (p<0.05) response to applied ovsynch protocol compared with the CG. According to the obtained results, it can be concluded that feed additive for mycotoxins management had a positive impact on dairy cow health.

Risk-Benefit Assessment of Feed Additives in the One Health Perspective

Safety and sustainability of animal feeds is a pillar of the safety of the entire food chain. Feed additive assessment incorporates consumer safety as well as animal health and welfare, which, in turn, can affect productivity and hence food security. The safety of feed users and the environment are other important components of the assessment process which, therefore, builds on a One Health perspective. In several instances the assessment entails a balanced assessment of benefits and risks for humans, animals and/or the environment. Three case studies are selected to discuss issues for a consistent framework on Risk-Benefit Assessment (RBA) of feed additives, based on EFSA opinions and literature: (a) Supplementation of feeds with trace elements with recognized human toxicity (cobalt, iodine) - RBA question: can use levels, hence human exposure, be reduced without increasing the risk of deficiency in animals?; (b) Aflatoxin binders in dairy animals - RBA question: can the use reduce the risk for human health due to aflatoxin M1, without unexpected adverse effects for animals or humans?; (c) Use of formaldehyde as preservative in feedstuffs to prevent microbial contamination - RBA question: is the reduction of microbiological risks outweighed by risks for the consumers, farmed animals or the workers? The case studies indicate that the safety of use of feed additives can involve RBA considerations which fit into a One Health perspective. As in other RBA circumstances, the main issues are defining the question and finding “metrics” that allow a R/B comparison; in the case of feed additives, R and B may concern different species (farm animals and humans). A robust assessment of animal requirements, together with sustainability considerations, might be a significant driving force for a RBA leading to a safe and effective use.

Effects of aflatoxin B1 and monensin interaction on liver and intestine of poultry – influence of a biological additive (Pichia kudriavzevii RC001)

The aim of this study was to evaluate the effects of aflatoxin B1 (AFB1) and monensin (MONS) interaction on the liver and intestinal histological changes in poultry, and the influence of Pichia kudriavzevii RC001. One-day-old commercial line (Ross 308) broilers (n=120) were individually weighed and randomly assigned to 8 treatments (15 broilers/treatment, 5 broilers per cage and 3 replicates/treatment). The experimental diets were: Group 1: basal diet (BD); Group 2: BD + MONS (50 mg/kg); Group 3: BD + P. kudriavzevii RC001 (1 g/kg); Group 4: BD + AFB1 (100 μg/kg); Group 5: BD + MONS + P. kudriavzevii RC001; Group 6: BD + AFB1 + P. kudriavzevii RC001; Group 7: BD + AFB1 + MONS + P. kudriavzevii RC001; Group 8: BD + AFB1 + MONS. When MONS was added, the typical AFB1 macroscopic and microscopic alterations were intensified. The P. kudriavzevii RC001 cytotoxicity and genotoxicity assays with Vero cells and with broiler chicken’s erythrocytes, demonstrated that P. kudriavzevii RC001 neither were non-cytotoxic nor genotoxic. When MONS was added in the presence of P. kudriavzevii RC001, the toxic effect of AFB1 on liver was not prevented. When P. kudriavzevii was present alone, the same prevention of the pathological damage was observed in the intestine of poultry fed with AFB1. The smallest apparent absorption area was obtained when AFB1 and MONS were added in the feed (P<0.05). AFB1 and MONS interaction demonstrated important toxic effects. Although P. kudriavzevii was effective in ameliorating the adverse effects of AFB1 alone on liver pathology and gut morphology, it was not able to diminish the toxic effects of AFB1 in presence of MONS. It suggests that P. kudriavzevii could be used as feed additive or counteracting the toxic effects of AFB1 in poultry production in the absence of MONS.

Mycotoxins—Prevention, Detection, Impact on Animal Health

Mycotoxins are defined as secondary metabolites of some species of mold fungi. They are present in many foods consumed by animals. Moreover, they most often contaminate products of plant and animal origin. Fungi of genera Fusarium, Aspergillus, and Penicillum are most often responsible for the production of mycotoxins. They release toxic compounds that, when properly accumulated, can affect many aspects of breeding, such as reproduction and immunity, as well as the overall liver detoxification performance of animals. Mycotoxins, which are chemical compounds, are extremely difficult to remove due to their natural resistance to mechanical, thermal, and chemical factors. Modern methods of analysis allow the detection of the presence of mycotoxins and determine the level of contamination with them, both in raw materials and in foods. Various food processes that can affect mycotoxins include cleaning, grinding, brewing, cooking, baking, frying, flaking, and extrusion. Most feeding processes have a variable effect on mycotoxins, with those that use high temperatures having the greatest influence. Unfortunately, all these processes significantly reduce mycotoxin amounts, but they do not completely eliminate them. This article presents the risks associated with the presence of mycotoxins in foods and the methods of their detection and prevention.

Agronomic Factors Influencing the Scale of Fusarium Mycotoxin Contamination of Oats

Seven agronomic factors (crop season, farming system, harvest date, moisture, county, oat variety, and previous crop) were recorded for 202 oat crops grown across Ireland, and samples were analysed by LC-MS/MS for four major Fusarium mycotoxins: deoxynivalenol (DON), zearalenone (ZEN), T-2 toxin and HT-2 toxin. Type A trichothecenes were present in 62% of crops, with 7.4% exceeding European regulatory limits. DON (6.4%) and ZEN (9.9%) occurrences were relatively infrequent, though one and three samples were measured over their set limits, respectively. Overall, the type of farming system and the previous crop were the main factors identified as significantly influencing mycotoxin prevalence or concentration. Particularly, the adherence to an organic farming system and growing oats after a previous crop of grass were found to decrease contamination by type A trichothecenes. These are important findings and may provide valuable insights for many other types of cereal crops as Europe moves towards a much greater organic-based food system.

Protective effect of a new generation of activated and purified bentonite in combination with yeast and phytogenic substances on mycotoxin challenge in pigs

The study aimed to investigate the efficacy of new mycotoxin adsorbents based on purified and activated bentonites combined with yeast and phytogenic compounds in fattening pigs. The experiment involved 96 pigs (31.2±2.4 kg). Control (C) group was fed a diet naturally contaminated with mycotoxins (5 mg/kg deoxynivalenol, DON) without an adsorbent. Treated groups received the feed with mycotoxin adsorbents: purified and activated bentonite (T1), purified and activated bentonite, yeast derivatives, phytogenic substances (T2), and purified, activated, and sulphurated bentonite with phytogenic substances (T3). Evaluated parameters involved growth performance, organ weight, small intestine and liver histopathology, complete blood count, serum biochemistry, antioxidant status of the organism and total and free DON content in urine. In all treated groups, an significant increase in intestinal GSH and GSH/GSSG ratio was observed when compared to C. No significant effects on liver and kidney weight, complete blood count, serum or intestinal malondialdehyde concentration, or total/free DON content in urine were observed. All adsorbents improved histopathological findings in the liver when compared to C. Moreover, T1, and T2 groups showed no presence of inflammatory reaction or necrotic changes in the livers. Although, mycotoxin adsorbents investigated in this study had no significant impact on pig growth performance, they reduced the oxidative stress, and on the tissue level they protected the jejunal tissue and liver parenchyma under deoxynivalenol challenge.

Effect of Natural Sorbents in the Diet of Fattening Pigs on Meat Quality and Suitability for Processing

The effect of three natural sorbents added to the diet of pigs on the composition and physicochemical properties of two skeletal muscles-the musculusLongissimuslumborum (MLL) and musculussemimembranosus (MSM) of crossbred pigs were evaluated. The experiment was carried out on a farm in two production cycles. The addition of biochar (trial 1) significantly influenced instrumental color parameters, shear force and energy, and the oxidative stability of the skeletal muscles, while the proximate composition, pH, texture, and water-holding capacity (WHC) parameters did not differ significantly between groups in either of the two muscles. Similarly, no statistical differences were noted in the proximate chemical composition, texture parameters, or WHC of the meat in trial 2. The addition of both sorbents was associated with a significantly (p ≤ 0.01) lower content of haem pigments in the MLL and MSM, which was accompanied by a significantly (p ≤ 0.05) higher lightness (L*). Moreover, the MLL muscle of the pigs had higher oxidative stability, as well as lower drip loss (DL). In turn, the MSM of pigs had a significantly lower pH compared to the control group, however, the ultimate pH (48 h) in all groups was within the acceptable range (5.50-5.80). Summing up, the sorbents used are a safe ingredient in the diet of pigs, however, there is a need to continue and strengthen this line of research, including the relationships linking the future production goals of pig farming and processing potential in the meat industry with current climate policy.

Fumonisin B1 Accumulates in Chicken Tissues over Time and This Accumulation Was Reduced by Feeding Algo-Clay

The toxicokinetics of the food and feed contaminant Fumonisin B (FB) are characterized by low oral absorption and rapid plasma elimination. For these reasons, FB is not considered to accumulate in animals. However, recent studies in chicken and turkey showed that, in these species, the hepatic half-elimination time of fumonisin B1 (FB1) was several days, suggesting that FB1 may accumulate in the body. For the present study, 21-day-old chickens received a non-toxic dose of around 20 mg FB1 + FB2/kg of feed to investigate whether FB can accumulate in the body over time. Measurements taken after four and nine days of exposure revealed increased concentrations of sphinganine (Sa) and sphingosine (So) over time in the liver, but no sign of toxicity and no effect on performances were observed at this level of FB in feed. Measurements of FB in tissues showed that FB1 accumulated in chicken livers from four to nine days, with concentrations of 20.3 and 32.1 ng FB1/g observed, respectively, at these two exposure periods. Fumonisin B2 (FB2) also accumulated in the liver, from 0.79 ng/g at four days to 1.38 ng/g at nine days. Although the concentrations of FB found in the muscles was very low, an accumulation of FB1 over time was observed in this tissue, with concentrations of 0.036 and 0.072 ng FB1/g being measured after four and nine days of exposure, respectively. Feeding algo-clay to the chickens reduced the accumulation of FB1 in the liver and muscle by , approximately 40 and 50% on day nine, respectively. By contrast, only a weak non-significant effect was observed on day four. The decrease in the concentration of FB observed in tissues of chickens fed FB plus algo-clay on day nine was accompanied by a decrease in Sa and So contents in the liver compared to the levels of Sa and So measured in chickens fed FB alone. FB1 in the liver and Sa or So contents were correlated in liver tissue, confirming that both FB1 and Sa are suitable biomarkers of FB exposure in chickens. Further studies are necessary to determine whether FB can accumulate at higher levels in chicken tissues with an increase in the time of exposure and in the age of the animals.

The Reduction of the Combined Effects of Aflatoxin and Ochratoxin A in Piglet Livers and Kidneys by Dietary Antioxidants

The purpose of this study was to investigate the combined effects of aflatoxin B1 and ochratoxin A on protein expression and catalytic activities of CYP1A2, CYP2E1, CYP3A29 and GSTA1 and the preventive effect of dietary byproduct antioxidants administration against these mycotoxin damage. Three experimental groups (E1, E2, E3) and one control group (C) of piglets after weaning (TOPIGS-40 hybrid) were fed with experimental diets for 30 days. A basal diet containing normal compound feed for starter piglets was used as a control treatment and free of mycotoxin. The experimental groups were fed as follows: E1—basal diet plus a mixture (1:1) of two byproducts (grapeseed and sea buckthorn meal), E2—the basal diet experimentally contaminated with mycotoxins (479 ppb OTA and 62ppb AFB1) and E3—basal diet containing 5% of the mixture (1:1) of grapeseed and sea buckthorn meal and contaminated with the mix of OTA and AFB1. After 4 weeks, the animals were slaughtered, and tissue samples were taken from liver and kidney in order to perform microsomal fraction isolation, followed by protein expression and enzymatic analyses. The protein expressions of CYP2E1 and CYP3A29 were up-regulated in an insignificant manner in liver, whereas in kidney, those of CYP1A2, CYP2E1 and CYP3A29 were down-regulated. The enzymatic activities of CYP1A2, CYP2E1 and CYP3A29 decreased in liver, in a significant manner, whereas in kidney, these increased significantly. The co-presence of the two mycotoxins and the mixture of grape seed and sea buckthorn meal generated a tendency to return to the control values, which suggest that grapeseed and sea buckthorn meal waste represent a promising source in counteracting the harmful effect of ochratoxin A and aflatoxin B.

The role of soils in provision of genetic, medicinal and biochemical resources

Intact, 'healthy' soils provide indispensable ecosystem services that largely depend on the biotic activity. Soil health is connected with human health, yet, knowledge of the underlying soil functioning remains incomplete. This review highlights selected services, i.e. (i) soil as a genetic resource and hotspot of biodiversity, forming the basis for providing (ii) biochemical resources and (iii) medicinal services and goods. Soils harbour an unrivalled biodiversity of organisms, especially microorganisms. Some of the abilities of autochthonous microorganisms and their relevant enzymes serve (i) to improve natural soil functions and in particular plant growth, e.g. through beneficial plant growth-promoting, symbiotic and mycorrhizal microorganisms, (ii) to act as biopesticides, (iii) to facilitate biodegradation of pollutants for soil bioremediation and (iv) to yield enzymes or chemicals for industrial use. Soils also exert direct effects on human health. Contact with soil enriches the human microbiome, affords protection against allergies and promotes emotional well-being. Medicinally relevant are soil substrates such as loams, clays and various minerals with curative effects as well as pharmaceutically active organic chemicals like antibiotics that are formed by soil microorganisms. By contrast, irritating minerals, soil dust inhalation and misguided soil ingestion may adversely affect humans. This article is part of the theme issue 'The role of soils in delivering Nature's Contributions to People.

Additives in pet food: are they safe?

A good, nutritious diet is essential for the health and well-being of our domestic pets. Today, most pet dogs and cats are fed highly processed food bearing little resemblance to canine and feline ancestral diets. Additives are included in processed pet food to provide nutritional benefits, ensure food safety, and maintain the desirable features of colour, flavour, texture, stability and resistance to spoilage. This paper reviews the safety of various additives in processed pet food. Labelling, safety assessment, and ethical concerns regarding existing toxicity testing procedures are also considered. The adequacy of testing for many additives and the scientific basis for determining safety are questioned. Additives can be synthetic or 'natural' although the distinction can be blurred when naturally derived substances are synthesised in the laboratory, or extracted using a high level of physical and chemical processing. Although additives play important roles in processed food production, updated strategies and technologies may be required to establish their safety in the pet food industry.

Combining Experimental Isotherms, Minimalistic Simulations, and a Model to Understand and Predict Chemical Adsorption onto Montmorillonite Clays

An attractive approach to minimize human and animal exposures to toxic environmental contaminants is the use of safe and effective sorbent materials to sequester them. Montmorillonite clays have been shown to tightly bind diverse toxic chemicals. Due to their promise as sorbents to mitigate chemical exposures, it is important to understand their function and rapidly screen and predict optimal clay-chemical combinations for further testing. We derived adsorption free-energy values for a structurally and physicochemically diverse set of toxic chemicals using experimental adsorption isotherms performed in the current and previous studies. We studied the diverse set of chemicals using minimalistic MD simulations and showed that their interaction energies with calcium montmorillonite clays calculated using simulation snapshots in combination with their net charge and their corresponding solvent's dielectric constant can be used as inputs to a minimalistic model to predict adsorption free energies in agreement with experiments. Additionally, experiments and computations were used to reveal structural and physicochemical properties associated with chemicals that can be adsorbed to calcium montmorillonite clay. These properties include positively charged groups, phosphine groups, halide-rich moieties, hydrogen bond donor/acceptors, and large, rigid structures. The combined experimental and computational approaches used in this study highlight the importance and potential applicability of analogous methods to study and design novel advanced sorbent systems in the future, broadening their applicability for environmental contaminants.

Modification of the effects of aflatoxin B1 on the glutathione system and its regulatory genes by zeolite

The purpose of the present study was to use oxidative stress markers for investigating the effect of zeolite (315 mg/kg of complete feed) in the case of aflatoxin B1 contamination (92 μg/kg complete feed). In a 21-day feeding trial with broiler chickens, oxidative stress parameters such as conjugated dienes, conjugated trienes, malondialdehyde, reduced glutathione content and glutathione peroxidase activity were not changed significantly by supplementation with this mycotoxin absorbent. The relative gene expression of transcription factors KEAP1 and NRF2 was not modified by the absorbent either. Still, the expression of GSS, GSR and GPX4 genes increased significantly due to the aluminosilicate supplementation. The results suggest that zeolite reduced lipid peroxidation in the blood plasma but not in the red blood cell haemolysate or the kidney. The relative expression of the genes encoding the glutathione redox system also changed as a result of zeolite supplementation, but these changes were not found at the protein level.

Phosphorus speciation in soils with low to high degree of saturation due to swine slurry application

Soils with continuous application of swine slurry (SS) may present high phosphorus (P) content and high risk for environmental pollution. The aim of this study was to characterize the forms of phosphorus accumulation in 15 fields with increasing degrees of P saturation (DPS) in a watershed with a high density of swine farming. Soil samples collected from 0 to 10 cm were chemically characterized for water soluble phosphorus (WSP), DPS, Hedley chemical fractionation, and chemical speciation by P K-edge XANES. WSP increased linearly to a value of 137% of DPS, with subsequent stabilization at 2.7 mg kg^-1. Only the inorganic fractions of the chemical fractionation changed with increasing DPS. Phosphorus forms considered labile increased up to 144% of DPS, with subsequent stabilization. The moderately labile fraction 0.1 M NaOH and non-labile 1 M HCl increased exponentially. Phosphorus K-edge XANES analysis demonstrated that P associated to apatite, amorphous aluminum minerals, and goethite were the main forms of P found and only the latter had a correlation with DPS (-0.57*). With increasing DPS, there are changes in the dynamics of P in the soil, with a reduction in forms associated to Fe and an increase in forms linked to Al. The forms linked to Al buffer the WSP and are recovered in the first inorganic fractions of the Hedley chemical fractionation.

Metabolism of Zearalenone in the Rumen of Dairy Cows with and without Application of a Zearalenone-Degrading Enzyme

The mycotoxin zearalenone (ZEN) is a frequent contaminant of animal feed and is well known for its estrogenic effects in animals. Cattle are considered less sensitive to ZEN than pigs. However, ZEN has previously been shown to be converted to the highly estrogenic metabolite α-zearalenol (α-ZEL) in rumen fluid in vitro. Here, we investigate the metabolism of ZEN in the reticulorumen of dairy cows. To this end, rumen-fistulated non-lactating Holstein Friesian cows (n = 4) received a one-time oral dose of ZEN (5 mg ZEN in 500 g concentrate feed) and the concentrations of ZEN and ZEN metabolites were measured in free rumen liquid from three reticulorumen locations (reticulum, ventral sac and dorsal mat layer) during a 34-h period. In all three locations, α-ZEL was the predominant ZEN metabolite and β-zearalenol (β-ZEL) was detected in lower concentrations. ZEN, α-ZEL and β-ZEL were eliminated from the ventral sac and reticulum within 34 h, yet low concentrations of ZEN and α-ZEL were still detected in the dorsal mat 34 h after ZEN administration. In a second step, we investigated the efficacy of the enzyme zearalenone hydrolase ZenA (EC 3.1.1.-, commercial name ZENzyme^®, BIOMIN Holding GmbH, Getzersdorf, Austria) to degrade ZEN to the non-estrogenic metabolite hydrolyzed zearalenone (HZEN) in the reticulorumen in vitro and in vivo. ZenA showed a high ZEN-degrading activity in rumen fluid in vitro. When ZenA was added to ZEN-contaminated concentrate fed to rumen-fistulated cows (n = 4), concentrations of ZEN, α-ZEL and β-ZEL were significantly reduced in all three reticulorumen compartments compared to administration of ZEN-contaminated concentrate without ZenA. Upon ZenA administration, degradation products HZEN and decarboxylated HZEN were detected in the reticulorumen. In conclusion, endogenous metabolization of ZEN in the reticulorumen increases its estrogenic potency due to the formation of α-ZEL. Our results suggest that application of zearalenone hydrolase ZenA as a feed additive may be a promising strategy to counteract estrogenic effects of ZEN in cattle.

Assessment of Food By-Products' Potential for Simultaneous Binding of Aflatoxin B1 and Zearalenone

In this study, eight food by-products were investigated as biosorbent approaches in removing mycotoxin load towards potential dietary inclusion in animal feed. Among these food-derived by-products, grape seed (GSM) and seabuckthorn (SBM) meals showed the most promising binding capacity for Aflatoxin B1 (AFB1) and Zearalenone (ZEA), measured as percent of adsorbed mycotoxin. Furthermore, we explored the mycotoxin sequestering potential by screening the effect of time, concentration, temperature and pH. Comparative binding efficacy was addressed by carrying out adsorption experiments in vitro. The highest mycotoxin adsorption was attained using 30 mg of by-product for both GSM (85.9% AFB1 and 83.7% ZEA) and SBM (68% AFB1 and 84.5% ZEA). Optimal settings for the experimental factors were predicted employing the response surface design. GSM was estimated to adsorb AFB1 optimally at a concentration of 29 mg/mL, pH 5.95 and 33.6 °C, and ZEA using 28 mg/mL at pH 5.76 and 31.7 °C. Favorable adsorption of AFB1 was estimated at 37.5 mg of SBM (pH 8.1; 35.6 °C), and of ZEA at 30.2 mg of SBM (pH 5.6; 29.3 °C). Overall, GSM revealed a higher binding capacity compared with SBM. In addition, the two by-products showed different specificity for the binary-mycotoxin system, with SBM having higher affinity towards ZEA than AFB1 (Kf = 0.418 and 1/n = 0.213 vs. Kf = 0.217 and 1/n = 0.341) and GSM for AFB1 in comparison with ZEA (Kf = 0.367 and 1/n = 0.248 vs. Kf = 0.343 and 1/n = 0.264). In conclusion, this study suggests that GSM and SBM represent viable alternatives to commercial biosorbent products.

Novel strategies for degradation of aflatoxins in food and feed: A review

Aflatoxins are toxic secondary metabolites mainly produced by Aspergillus fungi, posing high carcinogenic potency in humans and animals. Dietary exposure to aflatoxins is a global problem in both developed and developing countries especially where there is poor regulation of their levels in food and feed. Thus, academics have been striving over the decades to develop effective strategies for degrading aflatoxins in food and feed. These strategies are technologically diverse and based on physical, chemical, or biological principles. This review summarizes the recent progress on novel aflatoxin degradation strategies including irradiation, cold plasma, ozone, electrolyzed oxidizing water, organic acids, natural plant extracts, microorganisms and enzymes. A clear understanding of the detoxification efficiency, mechanism of action, degradation products, application potential and current limitations of these methods is presented. In addition, the development and future perspective of nanozymes in aflatoxins degradation are introduced.

Usability of graphene oxide as a mycotoxin binder: In vitro study

Mycotoxin management in agriculture is an essential challenge for maintaining the health of both animals and humans. Choosing the right adsorbent is still a question for many breeders and an important criterion for feed manufacturers. New adsorbents are still being sought. Graphene oxide is a promising material in the field of nanotechnology, which excels in its adsorption properties. Presented in vitro study investigates graphene oxide for the binding of mycotoxins from crushed wheat. The results show that graphene oxide has an adsorption capacity for aflatoxin 0.045 mg/g, zearalenone 0.53 mg/g and deoxynivalenol 1.69 mg/g at 37° C. In vitro simulation of crushed wheat digestion showed rapid adsorption during the gastric phase. Of the minerals, Mg, Cu and Zn were the most adsorbed. The applied dose of graphene oxide of 10 mg/g caused only a slight inhibition of the digestive enzymes α-amylase and trypsin compared to pepsin and gastric lipase. In vitro results indicated the suitability of graphene oxide in the adsorption of the aflatoxin, zearalenone and deoxynivalenol.

Low Doses of Mycotoxin Mixtures below EU Regulatory Limits Can Negatively Affect the Performance of Broiler Chickens: A Longitudinal Study

Several studies have reported a wide range of severe health effects as well as clinical signs, when livestock animals are exposed to high concentration of mycotoxins. However, little is known regarding health effects of mycotoxins at low levels. Thus, a long-term feeding trial (between May 2017 and December 2019) was used to evaluate the effect of low doses of mycotoxin mixtures on performance of broiler chickens fed a naturally contaminated diet. In total, 18 successive broiler performance trials were carried out during the study period, with approximately 2200 one-day-old Ross-308 chicks used for each trial. Feed samples given to birds were collected at the beginning of each trial and analysed for multi-mycotoxins using a validated LC-MS/MS method. Furthermore, parameters including feed intake, body weight and feed efficiency were recorded on a weekly basis. In total, 24 mycotoxins were detected in samples analysed with deoxynivalenol (DON), zearalenone (ZEN), fumonisins (FBs), apicidin, enniatins (ENNs), emodin and beauvericin (BEV), the most prevalent mycotoxins. Furthermore, significantly higher levels (however below EU guidance values) of DON, ZEN, FBs, BEV, ENNs and diacetoxyscirpenol (DAS) were detected in 6 of the 18 performance trials. A strong positive relationship was observed between broilers feed efficiency and DON (R² = 0.85), FBs (R² = 0.53), DAS (R² = 0.86), ZEN (R² = 0.92), ENNs (R² = 0.60) and BEV (R² = 0.73). Moreover, a three-way interaction regression model revealed that mixtures of ZEN, DON and FBs (p = 0.01, R² = 0.84) and ZEN, DON and DAS (p = 0.001, R² = 0.91) had a statistically significant interaction effect on the birds’ feed efficiency. As farm animals are often exposed to low doses of mycotoxin mixtures (especially fusarium mycotoxins), a cumulative risk assessment in terms of measuring and mitigating against the economic, welfare and health impacts is needed for this group of compounds.

Spirulina platensis mediated the biochemical indices and antioxidative function of Nile tilapia (Oreochromis niloticus) intoxicated with aflatoxin B1

Aflatoxicosis is one of the threats that cause severe mortalities in fish farms. The dietary functional additives are a friendly approach attributed to beneficial effects on aquatic animals. The study aimed at evaluating the impact of Spirulina platensis (SP) on the biochemical indices and antioxidative function of Nile tilapia (Oreochromis niloticus) intoxicated with aflatoxin B₁ (AFB₁). A control diet and 3 test diets were enriched with 0% SP/0 mg AFB₁/kg (control), 1% SP (SP), 2.5 mg AFB₁/kg diet (AFB₁), and 1% SP+2.5 mg AFB₁/kg diet (SP/AFB₁). The diets were supplied to three aquaria for each group twice daily at the rate of 2.5% for 30 days. The blood alanine transaminase (ALT), alkaline phosphatase (ALP), and aspartate transaminase (AST) were significantly increased by AFB₁ toxicity with regards to fish fed the control and SP diets (P < 0.05). The inclusion of SP in the diet of tilapia intoxicated with AFB₁ lowered the levels of ALT, AST, and ALP in comparison to fish contaminated with AFB₁ without SP (P < 0.05). The total blood protein and albumin were decreased in fish contaminated with AFB₁ (P < 0.05); however, the dietary SP resulted in improving the blood protein and albumin with similar levels with the control and SP diets. The urea and creatinine were increased in tilapia fed AFB₁ diet without SP (P < 0.05); however, the inclusion of SP reduced the levels of urea and creatinine with similar levels with the control and SP diets. The antioxidative capacity of Nile tilapia fed SP and contaminated with AFB₁ is expressed by superoxide dismutase (SOD), glutathione (GSH), and malondialdehyde (MDA) concentration. The activities of SOD and GSH were decreased by AFB₁ (P < 0.05); however, dietary SP increased the SOD and GSH in fish fed AFB₁. On the other hand, the concentration of MDA was increased in tilapia fed AFB₁ (P < 0.05); however, SP decreased the level of MDA in fish fed AFB₁. In conclusion, the application of SP in the aquafeed seems to be an innovative approach to relieve the toxic influences of AFB₁ on aquatic animals.

Comparative In Vitro Assessment of a Range of Commercial Feed Additives with Multiple Mycotoxin Binding Claims

Contamination of animal feed with multiple mycotoxins is an ongoing and growing issue, as over 60% of cereal crops worldwide have been shown to be contaminated with mycotoxins. The present study was carried out to assess the efficacy of commercial feed additives sold with multi-mycotoxin binding claims. Ten feed additives were obtained and categorised into three groups based on their main composition. Their capacity to simultaneously adsorb deoxynivalenol (DON), zearalenone (ZEN), fumonisin B1 (FB1), ochratoxin A (OTA), aflatoxin B1 (AFB1) and T-2 toxin was assessed and compared using an in vitro model designed to simulate the gastrointestinal tract of a monogastric animal. Results showed that only one product (a modified yeast cell wall) effectively adsorbed more than 50% of DON, ZEN, FB1, OTA, T-2 and AFB1, in the following order: AFB1 > ZEN > T-2 > DON > OTA > FB1. The remaining products were able to moderately bind AFB1 (44–58%) but had less, or in some cases, no effect on ZEN, FB1, OTA and T-2 binding (<35%). It is important for companies producing mycotoxin binders that their products undergo rigorous trials under the conditions which best mimic the environment that they must be active in. Claims on the binding efficiency should only be made when such data has been generated.