The role of mycotoxins in the health and performance of dairy cows

Exposure of Cattle Breeding Herds to Naturally Co-Contaminated Zearalenone and Deoxynivalenol: The Relevance of a Urinary Mycotoxin Monitoring System for Herd Health and Food Safety

The widespread presence of Fusarium mycotoxins in animal feed is a global issue, not only for the health of livestock but also for ensure the safety of food as an end product. High concentrations of zearalenone (ZEN) and deoxynivalenol (DON) have been detected in the diets of Japanese Black (JB) and Holstein Friesian (HF) breeding herds. Consequently, we monitored serum biochemical parameters over a long time in both herds, focusing on anti-Müllerian hormone (AMH) levels and acute-phase inflammation. Additionally, urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) and progesterone levels were measured in the HF herd. The JB herd, a ZEN-dominant model with low DON contamination, demonstrated ZEN levels that exceeded the Japanese limit in the purchased total mixed rations (TMR). Conversely, the HF herd, which primary consumes DON-dominant feed with low ZEN contamination, had high DON levels in the dent corn silage. Specifically, the JB herd's TMR contained 1.79 mg/kg ZEN and 0.58 mg/kg DON, whereas the HF herd's silage had 15.3 mg/kg DON (dried sample) and 0.1 mg/kg ZEN. Enzyme-linked immunoassay were used to measure urinary ZEN-DON levels following confirmation through liquid chromatography-tandem mass spectrometry. Urinary ZEN-DON levels measured were significantly correlated (p < 0.05, r > 0.6) in both herds. In the HF herd, AMH levels increased (p = 0.01) and serum amyloid A (SAA) levels decreased (p = 0.02) when contaminated and at the end of the monitoring period. Additionally, urinary ZEN and DON levels were significantly correlated with SAA levels (ZEN: p = 0.00, r = 0.46; DON: p = 0.03, r = 0.33), with an increase in ZEN and DON levels resulting in higher SAA levels. The JB herd showed no significant differences. Additionally, in the HF herd, 8-OHdG/Cre levels increased significantly during major contamination periods (p < 0.05). Clinical data from the HF herd indicated an increase in mastitis cases and treatment rates during periods of major contamination. Abortion rates in the HF herd decreased from 22.9% (before monitoring) to 8.9% (during the high contamination period) and finally to 1% (at the end of the monitoring period), with corresponding increases in progesterone levels. ZEN-DON contamination adversely affects breeding cattle's productivity, reproductive performance, and health. Therefore, monitoring urinary ZEN-DON is valuable for detecting contaminants and ensuring the safety of food products.

Review: Strategies and technologies in preventing regulated and emerging mycotoxin co-contamination in forage for safeguarding ruminant health

Ruminants are often considered less susceptible to mycotoxins than monogastrics, owing to rumen microflora converting mycotoxins to less toxic compounds or several compounds present in the rumen-reticulum compartment, being able to bind the mycotoxin "mother" molecule that make them unavailable for absorption process in the gastro-intestinal tract of host animals. However, if ruminants consume feed contaminated by mycotoxins for long periods, their growth, development, and fertility can be compromised. Among regulated mycotoxins, the most studied and known for their effects are aflatoxins (AFs) AFB1, AFB2, AFG1 and AFG2, as well as the AFM1 for its high importance in dairy sector, deoxynivalenol (DON) and its metabolites 3/15 acetyl-DON and 3-glucoside DON, T-2 and HT-2 toxins, zearalenone, fumonisins, in particular that belong to the B class, and ochratoxin A. Furthermore, because of the emergence of multiple emerging mycotoxins that are detectable in feed utilised in ruminant diets, such as ensiled forage, there is now a growing focus on investigating these compounds by the scientific community to deepen their toxicity for animal health. Despite the enhancement of research, it is remarkable that there is a paucity of in vivo trials, as well as limited studies on nutrient digestibility and the impact of these molecules on rumen and intestinal functions or milk yield and quality. In this review, recent findings regarding the occurrence of regulated and emerging mycotoxins in forage and their possible adverse effects on dairy cattle are described, with special emphasis on animal performance and on rumen functionality.

Exploring the Efficacy of Using Geotrichum fermentans, Rhodotorula rubra, Kluyveromyce marxiamus, Clay Minerals, and Walnut Nutshells for Mycotoxin Remediation

The aim of this study was to evaluate the effectiveness of nine different biological compounds to reduce mycotoxins concentrations. The hypothesis of this study was that a static in vitro gastrointestinal tract model, as an initial screening tool, can be used to simulate the efficacy of Geotrichum fermentans, Rhodotorula rubra, Kluyveromyce marxiamus yeast cell walls and their polysaccharides, red and white clay minerals, and walnuts nutshells claiming to detoxify AFB1, ZEA, DON, and T-2 toxin mycotoxins. Mycotoxin concentrations were analyzed using high-performance liquid chromatography (HPLC) with fluorescent (FLD) and ultraviolet detectors (UV). The greatest effects on reducing mycotoxin concentrations were determined as follows: for AFB1, inserted G. fermentans cell wall polysaccharides and walnut nutshells; for ZEA, inserted R. rubra and G. fermentans cell walls and red clay minerals; for DON, R. rubra cell wall polysaccharides and red clay minerals; and for T-2 toxin, R. rubra cell walls, K. marxianus, and G. fermentans cell wall polysaccharides and walnut nutshells. The present study indicated that selected mycotoxin-detoxifying biological compounds can be used to decrease mycotoxin concentrations.

Prevalence and concentration of mycotoxins in bovine feed and feed components: A global systematic review and meta-analysis

Mycotoxins are secondary metabolites produced by fungi and identified as contaminants in animal feed. They have potentially harmful effects, including carcinogenicity, mutagenicity, and repro-toxicity in animals and humans. As a result of climate change, there is the potential for a change in the prevalence and concentration of mycotoxins in animal feed components. This necessitates an assessment of the present and emerging threats to the food supply chain from mycotoxins. This systematic review and meta-analysis study synthesised studies on mycotoxin contamination and prevalence in cattle feed components. The studies were collected from scientific databases Web of Knowledge, Scopus, and Embase between 2011 and 2022. The meta-analysis synthesised 97 studies on the prevalence and the concentration of aflatoxins, ochratoxin A, deoxynivalenol, zearalenone, fumonisin and T-2/HT-2 toxins in feed components. Aflatoxin was highly prevalent (59 %), with a concentration of 2.58-3.92 μg kg-1 in feed components. Ochratoxin A had a global prevalence of 31 % with a concentration of 5.56-12.41 μg kg-1. Deoxynivalenol had a global concentration of 233.17-327.73 μg kg-1 and a prevalence of 74 %. Zearalenone had a prevalence of 70 % and a concentration of 42.47-66.19 μg kg-1. The concentration and prevalence of fumonisins was 232.19-393.07 μg kg-1 and 65 %, respectively. The prevalence and concentration of T-2/HT-2 toxins were 45 % and 23.54-35.12 μg kg-1, respectively. The synthesised concentration of the mycotoxins in the overall feed components was lower than the regulated and guidance values set by the European Union. However, in a few cases, the 95th percentile exceeded these concentration values due to high levels of uncertainty attributed to lower sample size, and thus, need to be considered while conducting risk assessments. The study highlights climates and regions likely to be conducive to the emergence of mycotoxin risk, especially considering the potential influences of climate change.

Anti-mycotoxin feed additives: effects on metabolism, mycotoxin excretion, performance, and total tract digestibility of dairy cows fed artificially multi-mycotoxin-contaminated diets

The aim of this study was to evaluate the effects of different anti-mycotoxin feed additives on the concentration of mycotoxins in milk, urine, and blood plasma of dairy cows fed artificially multi-mycotoxin-contaminated diets. Secondarily, performance, total-tract apparent digestibility of nutrients, and blood parameters were evaluated. Twelve multiparous cows (165 ± 45 d in milk, 557 ± 49 kg body weight, and 32.1 ± 4.57 kg/d milk yield at the start of the experiment) were blocked according to parity, milk yield, and days in milk and used in a 4 × 4 Latin square design experiment with 21-d periods, where the last 7 d were used for sampling and data analysis. Treatments were: 1) Mycotoxin group (MTX), basal diet (BD) without anti-mycotoxin feed additives; 2) Hydrated sodium calcium aluminosilicate (HSCA), HSCA added to the BD at 25g/cow/d; 3) Mycotoxin deactivator 15 (MD15), MD (Mycofix® Plus, dsm-firmenich) added to the BD at 15 g/cow/d; and 4) Mycotoxin deactivator 30 (MD30), MD added to the BD at 30 g/cow/d. Cows from all treatments were challenged with a blend of mycotoxins containing 404 μg aflatoxins B1 (AFB1), 5,025 μg deoxynivalenol (DON), 8,046 μg fumonisins (FUM), 195 μg T2 toxin (T2), and 2,034 μg of zearalenone (ZEN) added daily to the BD during the last 7 d of each period. Neither performance (milk yield and composition) nor nutrient digestibility was affected by treatments. All additives reduced aflatoxin M1 (AFM1) concentration in milk, whereas MD15 and MD30 group had lower excretion of AFM1 in milk than HSCA. DON, FUM, T2, or ZEN were not detected in milk of MD15 and MD30. Concentrations in milk of DON, FUM, T2, and ZEN were similar between MTX and HSCA. Except for AFM1, none of the analyzed mycotoxins were detected in urine of MD30 group. Comparing HSCA to MD treatments, the concentration of AFM1 was greater for HSCA, whereas MD30 was more efficient at reducing AFM1 in urine than MD15. AFM1, DON, FUM, and ZEN were not detected in the plasma of cows fed MD30, and DON was also not detected in MD15 group. Plasma concentration of FUM was lower for MD15, similar plasma FUM concentration was reported for HSCA and MTX. Plasma concentration of ZEN was lower for MD15 than MTX and HSCA. Serum concentrations of haptoglobin and hepatic enzymes were not affected by treatments. Blood concentration of sodium was lower in HSCA compared with MD15 and MD30 groups. In conclusion, the mycotoxin deactivator proved to be effective in reducing the secretion of mycotoxins in milk, urine, and blood plasma, regardless of the dosage. This reduction was achieved without adverse effects on milk production or total-tract digestibility in cows fed multi-mycotoxin-contaminated diets over a short-term period. Greater reductions in mycotoxin secretion were observed with full dose of MD.

In vitro effects of two environmental toxicants, beauvericin and glyphosate in Roundup, on cell numbers and steroidogenesis of bovine ovarian cells

Beauvericin is an emerging Fusariotoxin naturally occurring in cereal grains throughout the world whereas glyphosate (N-phosphonomethyl-glycine) is a non-selective systemic herbicide used worldwide. The purpose of this study is to evaluate a newly developed ovarian cell culture system (that includes both granulosa and theca cells) as an in vitro model for toxicological studies. Specifically, the effects of beauvericin and glyphosate in formulation with Roundup on ovarian cell numbers and steroid production were evaluated. Ovaries collected from cattle without luteal structures were sliced into 30-70 pieces each, and granulosa and theca cells were collected. Harvested cells were cultured for 48 h in 10% fetal bovine serum-containing medium followed by 48 h in serum-free medium containing testosterone (500 ng/mL; as an estrogen precursor) with the following eight treatments: (1) controls, (2) FSH (30 ng/mL) alone, (3) FSH plus insulin-like growth factor-1 (IGF1; 30 ng/mL), (4) FSH plus IGF1 plus beauvericin (3 µM), (5) FSH plus IGF1 plus glyphosate in Roundup (10 µg/mL), (6) FSH plus IGF1 plus fibroblast growth factor 9 (FGF9, 30 ng/mL), (7) a negative control without added testosterone, and (8) IGF1 plus LH (30 ng/mL) with basal medium without added testosterone. In the presence of FSH, IGF1 significantly increased cell numbers, estradiol and progesterone production by severalfold. Glyphosate in Roundup formulation significantly inhibited IGF1-induced cell numbers and estradiol and progesterone production by 89-94%. Beauvericin inhibited IGF1-induced cell numbers and estradiol and progesterone by 50-97% production. LH plus IGF1 significantly increased androstenedione secretion compared with controls without added testosterone indicating the presence of theca cells. In conclusion, the present study demonstrates that toxicological effects of beauvericin and glyphosate in Roundup formulation are observed in a newly developed ovarian cell model system and further confirms that both glyphosate and beauvericin may have the potential to impair reproductive function in cattle.

Heme Oxygenase-1 Regulates Zearalenone-Induced Oxidative Stress and Apoptosis in Sheep Follicular Granulosa Cells

Zearalenone (ZEA) is a common non-steroidal estrogenic mycotoxin found in a range of animal feeds and poses a serious threat to the reproductive health of farm animals and humans. However, the mechanism underlying ZEA-induced reproductive toxicity in sheep remains unknown. Granulosa cells are crucial for egg maturation and the fertility of female sheep. In this study, we aimed to examine the impact of different ZEA concentrations on sheep follicular granulosa cells and to elucidate the potential molecular mechanism underlying ZEA-induced toxicity using transcriptome sequencing and molecular biological approaches. Treating primary sheep follicular granulosa cells with different concentrations of ZEA promoted the overproduction of reactive oxygen species (ROS), increased lipid peroxidation products, led to cellular oxidative stress, decreased antioxidant enzyme activities, and induced cell apoptosis. Using transcriptome approaches, 1395 differentially expressed genes were obtained from sheep follicular granulosa cells cultured in vitro after ZEA treatment. Among them, heme oxygenase-1 (HMOX1) was involved in 11 biological processes. The protein interaction network indicated interactions between HMOX1 and oxidative and apoptotic proteins. In addition, N-acetylcysteine pretreatment effectively reduced the ZEA-induced increase in the expression of HMOX1 and Caspase3 by eliminating ROS. Hence, we suggest that HMOX1 is a key differential gene involved in the regulation of ZEA-induced oxidative stress and apoptosis in follicular granulosa cells. These findings provide novel insights into the prevention and control of mycotoxins in livestock.

A 2-year study reveals implications of feeding management and exposure to mycotoxins on udder health, performance, and fertility in dairy herds

We recently reported the ubiquitous occurrence of mycotoxins and their secondary metabolites in dairy rations and a substantial variation in the feeding management among Austrian dairy farms. The present study aimed to characterize to which extent these factors contribute to the fertility, udder health traits, and performance of dairy herds. During 2019 and 2020, we surveyed 100 dairy farms, visiting each farm 2 times and collecting data and feed samples. Data collection involved information on the main feed ingredients, nutrient composition, and the levels of mycotoxin and other metabolites in the diet. The annual fertility and milk data of the herds were obtained from the national reporting agency. Calving interval was the target criterion for fertility performance, whereas the percentage of primiparous and multiparous cows in the herd with somatic cell counts above 200,000 cells/mL was the criterion for impaired udder health. For each criterion, herds were classified into 3 groups: high/long, mid, and low/short, with the cut-off corresponding to the <25th and >75th percentiles and the rest of the data, respectively. Accordingly, for the calving interval, the cut-offs for the long and short groups were ≥400 and ≤380 d, for the udder health in primiparous cows were ≥20% and ≤8% of the herd, and for the udder health in multiparous cows were ≥35% and ≤20% of the herd, respectively. Quantitative approaches were further performed to define potential risk factors in the herds. The high somatic cell count group had higher dietary exposure to enniatins (2.8 vs. 1.62 mg/cow per d), deoxynivalenol (4.91 vs. 2.3 mg/cow per d), culmorin (9.48 vs. 5.72 mg/cow per d), beauvericin (0.32 vs. 0.18 mg/cow per d), and siccanol (13.3 vs. 5.15 mg/cow per d), and total Fusarium metabolites (42.8 vs. 23.2 mg/cow per d) and used more corn silage in the ration (26.9% vs. 17.3% diet DM) compared with the low counterparts. Beauvericin was the most substantial contributing variable among the Fusarium metabolites, as indicated by logistic regression and modeling analyses. Logistic analysis indicated that herds with high proportions of cows with milk fat-to-protein ratio >1.5 had an increased odds for a longer calving interval, which was found to be significant for primiparous cows (odds ratio = 5.5, 95% confidence interval = 1.65-21.7). As well, herds with high proportions of multiparous cows showing levels of milk urea nitrogen >30 mg/dL had an increased odds for longer calving intervals (odds ratio = 2.96, 95% confidence interval = 1.22-7.87). In conclusion, the present findings suggest that dietary contamination of Fusarium mycotoxins (especially emerging ones), likely due to increased use of corn silage in the diet, seems to be a risk factor for impairing the udder health of primiparous cows. Mismatching dietary energy and protein supply of multiparous cows contributed to reduced herd fertility performance.

Improving feed intake and rumen fermentation in lambs using mixed-dimensional attapulgite clay to adsorb naturally occurring mycotoxins

This experiment was conducted to evaluate the effects of including a mixed-dimensional attapulgite clay (MDA) into a naturally moldly diet for Hu lambs. Fifty male Hu lambs with similar initial body weight (28.24 ± 1.80 kg) were randomly allocated into five dietary treatments: a basal diet containing naturally occurring mycotoxins with 0, 0.5, 1.0, and 2.0 kg/t MDA, and basal diet with a commercial mycotoxin adsorbent Solis with montmorillonite as the major component at 1 kg/t. Both MDA and Solis increased average daily gain (ADG) and dry matter intake (DMI; P ≤ 0.004), and there was no difference in growth performance between MDA and Solis (P ≥ 0.26). The final body weight, DMI, and ADG were linearly increased with increasing MDA supplementation (P < 0.01). Lambs treated with both MDA and Solis demonstrated greater apparent digestibility of dry matter (DM), organic matter (OM), and energy compared with the control group (P ≤ 0.03), and there were no differences in nutrient digestibilities between MDA and Solis (P ≥ 0.38). Digestibility of CP was linearly increased with the increasing MDA supplementation (P = 0.01). Neither MDA nor Solis affected rumen total volatile fatty acid (TVFA) concentration (P ≥ 0.39), but decreased the acetate-to-propionate ratio and molar proportion of n-butyrate (P ≤ 0.01), and MDA also increased the concentration of ammonia (P = 0.003). Besides, increasing MDA supplementation linearly reduced the acetate-to-propionate ratio and molar proportion of n-butyrate (P = 0.01), but linearly and quadratically increased the concentration of ammonia (P ≥ 0.003). These results showed that the incorporation of MDA into a naturally moldy diet of Hu lambs yielded comparable results to the Solis product, with higher growth performance and nutrient digestibility but lower acetate-to-propionate ratio observed. In conclusion, including ≥ 1 kg/t of MDA in high mycotoxin risk diets for growing lambs improves feed intake and rumen fermentation.

Ruminal ergovaline and volatile fatty acid dynamics: Association with poor performance and a key growth regulator in steers grazing toxic tall fescue

Fescue toxicosis (FT) is produced by an ergot alkaloid (i.e., ergovaline [EV])-producing fungus residing in toxic fescue plants. Associations between EV, decreased weight gain and ruminal volatile fatty acids are unclear. Feces, rumen fluid, and blood were collected from 12 steers that grazed non-toxic (NT) or toxic (E +) fescue for 28 days. The E + group exhibited decreased propionate (P), increased acetate (A), and increased ruminal A:P ratio, with similar trends in feces. Plasma GASP-1 (G-Protein-Coupled-Receptor-Associated-Sorting-Protein), a myostatin inhibitor, decreased (day 14) only in E + steers. Ergovaline was present only in E + ruminal fluid and peaked on day 14. The lower ruminal propionate and higher A:P ratio might contribute to FT while reduced GASP-1 might be a new mechanism linked to E + -related weight gain reduction. Day 14 ergovaline zenith likely reflects ruminal adaptations favoring EV breakdown and its presence only in rumen points to local, rather than systemic effects.

Nutritive value of fermented soybean grains for ruminants

Fermented soybean grain (FSBG) is considered improper to use as a protein source in animal nutrition, since it is assumed that defects cause changes on its chemical composition and favor mycotoxins production, but chemical composition data does not support this theory and in vivo studies are missing. Thus, this study aimed to evaluate the effects of FSBG in feedlot lamb diets. For that, two types of FSBG (partially fermented and completely fermented, PFSBG and CFSBG) and one standard soybean grain (SSBG) were obtained and evaluated alone or as a component of experimental diets by in vitro and in vivo studies, where FSBG totally replaced SSBG in feedlot lamb diets, which was included in the experimental diets in 17.4% on dry matter basis as protein source. Before the studies, both soybeans were sent to a specialized laboratory where no mycotoxins were detected. As a result, lower DM and carbohydrate contents but higher crude protein, fiber, and indigestible NDF contents were measured in CFSBG than in SSBG. Furthermore, both types of FSBG showed lower digestibility in vitro dry matter (IVDMD) than SSBG when evaluated separately; however, when evaluated in experimental diets, the substitution of SSBG for FSBG did not affect IVDMD. It was also observed that FSBG also had less rumen-degradable protein than SSBG (mean 47.9 vs 86.4%). In the in vivo study, FSBG did not affect nutrient intake, apparent digestibility, or animal performance (i.e., average daily gain and carcass gain). Thus, mycotoxins-free FSBG may be an alternative to totally replace SSBG in feedlot lamb diets.

Use of reclaimed urban wastewater for the production of hydroponic barley forage: water characteristics, feed quality and effects on health status and production of lactating cows

The safety of reclaimed urban wastewater (RUW) for the production of hydroponic barley forage (HBF) was evaluated in terms of effluent and forage characteristics, as well as the health and performance of lactating cows. The study was conducted on a dairy farm equipped with two hydroponic chambers producing approximately 620 kg/d of HBF as fed. For experimental purposes, HBF was produced using RUW collected from an aqueduct plant processing urban wastewater in a membrane bioreactor treatment chain. A feeding trial was carried out with HBF derived from RUW. Sixty lactating cows were randomly assigned to two balanced groups fed a standard total mixed ration (TMR) or a TMR in which 10 kg of HBF replaced 1 kg of oat hay and 0.5 kg of maize. The experimental period lasted 7 weeks, including a 2-week adaptation period, during which each cow underwent a physical examination, BCS scoring, blood sampling for a complete blood count and biochemical panel, recording of body weight and milk yield and quality, including fatty acid composition and heavy metal content. Ruminal pH was continuously monitored by reticulorumen boluses, and nutrient digestibility and N balance were determined at week 7. RUW showed an acceptable microbial load and an overall good quality as irrigation water, even though the supply of N and P did not influence the yield and quality of HBF. The characteristics of HBF reflected the quality of RUW supplied to the hydroponic chambers and no anomalous components (i.e., high ion concentration) were found. Feeding RW-derived HBF to lactating cows had no major positive or negative effects on animal health and production, including milk quality, ruminal pH, in vivo digestibility, and N balance. The use of RUW under the conditions tested appears to be safe for the health status of lactating cows and the quality of the milk obtained. Overall, the results do not reveal any major limitations for the use of tertiary wastewater as irrigation water for the hydroponic production of forage barley, so that a wider use of wastewater in hydroponic systems seems realistic.

Effects of Supplementation of a Mycotoxin Mitigation Feed Additive in Lactating Dairy Cows Fed Fusarium Mycotoxin-Contaminated Diet for an Extended Period

Fusarium mycotoxins are inactivated by rumen flora; however, a certain amount can pass the rumen and reticulum or be converted into biological active metabolites. Limited scientific evidence is available on the impact and mitigation of Fusarium mycotoxins on dairy cows' performance and health, particularly when cows are exposed for an extended period (more than 2 months). The available information related to these mycotoxin effects on milk cheese-making parameters is also very poor. The objective of this study was to evaluate a commercially available mycotoxin mitigation product (MMP, i.e., TOXO® HP-R, Selko, Tilburg, The Netherlands) in lactating dairy cows fed a Fusarium mycotoxin-contaminated diet, and the repercussions on the dry matter intake, milk yield, milk quality, cheese-making traits and health status of cows. The MMP contains smectite clays, yeast cell walls and antioxidants. In the study, 36 lactating Holstein cows were grouped based on the number of days of producing milk, milk yield, body condition score and those randomly assigned to specific treatments. The study ran over 2 periods (March/May-May/July 2022). In each period, six animals/treatment were considered. The experimental periods consisted of 9 days of adaptation and 54 days of exposure. The physical activity, rumination time, daily milk production and milk quality were measured. The cows were fed once daily with the same total mixed ration (TMR) composition. The experimental groups consisted of a control (CTR) diet, with a TMR with low contamination, high moisture corn (HMC), and beet pulp; a mycotoxins (MTX) diet, with a TMR with highly contaminated HMC, and beet pulp; and an MTX diet supplemented with 100 g/cow/day of the mycotoxin mitigation product (MMP). The trial has shown that the use of MMP reduced the mycotoxin's negative effects on the milk yield and quality (protein, casein and lactose). The MTX diet had a lower milk yield and feed efficiency than the CTR and MMP HP-R diets. The MMP limited the negative effect of mycotoxin contamination on clotting parameters, mitigating the variations on some coagulation properties; however, the MMP inclusion tended to decrease the protein and apparent starch digestibility of the diet. These results provide a better understanding of mycotoxin risk on dairy cows' performances and milk quality. The inclusion of an MMP product mitigated some negative effects of the Fusarium mycotoxin contamination during this trial. The major effects were on the milk yield and quality in both the experimental periods. These results provide better insight on the effects of mycotoxins on the performance and quality of milk, as well as the cheese-making traits. Further analyses should be carried out to evaluate MMP's outcome on immune-metabolic responses and diet digestibility.

A network meta-analysis on the efficacy of different mycotoxin binders to reduce aflatoxin M1 in milk after aflatoxin B1 challenge in dairy cows

The objective of this network meta-analysis was to determine the efficacy of different mycotoxin binders (MTB) to reduce aflatoxin M1 (AFM1) in milk. A literature search was conducted to identify in vivo research papers from different databases. Inclusion criteria were in vivo, dairy cows, description of the MTB used, doses of MTB, aflatoxin inclusion in the diet, and concentration of AFM1 in milk. Twenty-eight papers with 131 data points were selected. Binders used in the studies were hydrated sodium calcium aluminosilicate (HSCAS), yeast cell wall (YCW), bentonite, and mixes of several MTB (MX). The response variables were AFM1 concentration, AFM1 reduction in milk, total AFM1 excreted in milk, and transfer of aflatoxin from feed to AFM1 in milk. Data were analyzed with CINeMA and GLIMMIX procedures with the WEIGHT statement of SAS (SAS Inst. Inc.). The AFM1 concentration in milk decreased for bentonite (0.3 µg/L ± 0.05; mean ± SE) and HSCAS (0.4 µg/L ± 0.12), and tended to decrease for MX (0.6 µg/L ± 0.13) but was similar for YCW (0.6 µg/L ± 0.12), compared with control (0.7 µg/L ± 0.12). The percentage reduction of AFM1 in milk was similar for all MTB and different from control with a range of reduction from 25% for YCW to 40% for bentonite. The excretion of AFM1 in milk was lower in YCW (5.3 µg/L ± 2.37), HSCAS (13.8 µg/L ± 3.31), and MX (17.1 µg/L ± 5.64), and not affected by bentonite (16.8 µg/L ± 3.33) compared with control (22.1 µg/L ± 5.33). The transfer of aflatoxin B1 from feed into AFM1 in milk was lowest in bentonite (0.6% ± 0.12), MX (1.04% ± 0.27), and HSCAS (1.04% ± 0.21), and not affected in YCW (1.4% ± 0.10), compared with control (1.7% ± 0.35). The meta-analysis results indicate that all MTB reduced the AFM1 transfer into milk, where bentonite had the highest capacity and YCW the lowest.

T-2 and HT-2 Toxins: Toxicity, Occurrence and Analysis: A Review

One of the major classes of mycotoxins posing serious hazards to humans and animals and potentially causing severe economic impact to the cereal industry are the trichothecenes, produced by many fungal genera. As such, indicative limits for the sum of T-2 and HT-2 were introduced in the European Union in 2013 and discussions are ongoing as to the establishment of maximum levels. This review provides a concise assessment of the existing understanding concerning the toxicological effects of T-2 and HT-2 in humans and animals, their biosynthetic pathways, occurrence, impact of climate change on their production and an evaluation of the analytical methods applied to their detection. This study highlights that the ecology of F. sporotrichioides and F. langsethiae as well as the influence of interacting environmental factors on their growth and activation of biosynthetic genes are still not fully understood. Predictive models of Fusarium growth and subsequent mycotoxin production would be beneficial in predicting the risk of contamination and thus aid early mitigation. With the likelihood of regulatory maximum limits being introduced, increased surveillance using rapid, on-site tests in addition to confirmatory methods will be required. allowing the industry to be proactive rather than reactive.

Measurement of serum short-chain fatty acid concentrations in cattle after oral administration of difructose anhydride III

Background and Aim

We previously reported the mitigation effects of difructose anhydride III (DFA III) on mycotoxins, such as zearalenon and sterigmatocystin, based on the urinary concentrations of these molecules in calves. This study was aimed at evaluating the effects of dietary supplementation of DFA III and the fermented status of DFA III in the intestine by comparing serum levels of short-chain fatty acid (SCFAs) in DFA III-supplemented cattle with those in non-supplemented control cattle.

Materials and Methods

Serum SCFA concentrations were measured in 30 Japanese Black heifers, aged 9-10 months, from two herds, using gas chromatography on days 0 (before DFA III supplementation), 9, and 14 after DFA III supplementation.

Results

A notably different trend was observed for isobutyric acid and enanthic acid, which may reflect the different fermentation status of supplementary DFA III in the intestine. Our results indicate the possibility that this trend observed in the intestinal tract following DFA III administration is associated with changes in the environment of intestinal bacterial flora, which may partially reflect the effects of DFA III supplementation on cattle.

Conclusion

Difructose anhydride III supplementation for at least 2 weeks affects the trend of blood SCFA concentrations in cattle. Our results provide evidence supporting the effects of DFA III on the intestinal environment and intestinal barrier function.

Practical Application of a Urinary Zearalenone Monitoring System for Feed Hygiene Management of a Japanese Black Cattle Breeding Herd-Relevance to Anti-Müllerian Hormone and Serum Amyloid A Clarified from a Two-Year Survey

In this study, a herd of Japanese Black (JB) breeding cattle with sporadic reproductive disorders was continuously monitored for an additional year to assess the effects of the urinary zearalenone (ZEN) concentration and changes in parameters (AMH and SAA) with time-lag variables and herd fertility (reproductive performance). This herd had high (exceeded the Japanese dietary feed regulations) urinary ZEN and rice straw ZEN concentrations (1.34 mg/kg). Long-term data of the herd with positive ZEN exposure revealed a decreasing ZEN concentration in urine and a gradual decrease in the AMH level with age. The AMH level was significantly affected by the ZEN value 2 months earlier and the AMH level in the previous month. The changes in ZEN and SAA values were significantly affected by the ZEN and SAA values in the previous month. Additionally, calving interval data between pre-monitoring and post-monitoring showed a significantly different pattern. Furthermore, the calving interval became significantly shorter between the time of contamination (2019) and the end of the monitoring period (2022). In conclusion, the urinary ZEN monitoring system may be a valuable practical tool for screening and detecting herd contamination in the field, and acute and/or chronic ZEN contamination in dietary feeds may affect herd productivity and the fertility of breeding cows.

Impact of Enniatin and Deoxynivalenol Co-Occurrence on Plant, Microbial, Insect, Animal and Human Systems: Current Knowledge and Future Perspectives

Fusarium mycotoxins commonly contaminate agricultural products resulting in a serious threat to both animal and human health. The co-occurrence of different mycotoxins in the same cereal field is very common, so the risks as well as the functional and ecological effects of mycotoxins cannot always be predicted by focusing only on the effect of the single contaminants. Enniatins (ENNs) are among the most frequently detected emerging mycotoxins, while deoxynivalenol (DON) is probably the most common contaminant of cereal grains worldwide. The purpose of this review is to provide an overview of the simultaneous exposure to these mycotoxins, with emphasis on the combined effects in multiple organisms. Our literature analysis shows that just a few studies on ENN-DON toxicity are available, suggesting the complexity of mycotoxin interactions, which include synergistic, antagonistic, and additive effects. Both ENNs and DON modulate drug efflux transporters, therefore this specific ability deserves to be explored to better understand their complex biological role. Additionally, future studies should investigate the interaction mechanisms of mycotoxin co-occurrence on different model organisms, using concentrations closer to real exposures.

Occurrence of zearalenone in dairy farms - A study on the determinants of exposure and risk assessment

The Azorean dairy industry is based on a semi-intensive model. Due to the few storage facilities and the large climatic fluctuations that characterize the Azores, the complete feed mixture (total mixed ration - TMR) is susceptible to the proliferation of a variety of fungi and mycotoxin contamination. Thus, chronic ingestion of these xenobiotics may lead to increased susceptibility to disease, loss of reproductive performance and, in the case of dairy cattle, decreased productivity and quality of milk produced. Since it is impossible to eliminate completely the presence of mycotoxins, it is essential to ensure the implementation of strategies to reduce their concentration in products intended for food and feed, as well as to monitor and control the levels present in food. This study aimed to evaluate the occurrence zearalenone (ZEA) in feed (TMR) in four dairy cattle farms on the Azorean Island of São Miguel and relate it to the occurrence of this mycotoxin in the milk produced, by associating several production and health indicators translated by the monthly milk contrast. To this end, the monthly milk contrast data, the determination of ZEA in the ingested feed and the (individual) milk samples from the four farms included in the study were used. Eighty-three (98.8%) of the milk samples under study had detectable ZEA levels (1.56 ± 1.36 μg/L), higher than reported in previous similar studies. Although ZEA concentration was not significantly associated with any production indicator analyzed (days in milk, age at calving, milk yield, protein content, butyrate content, somatic cell concentration and urea), it was found that the production regime and type of feed management is a major factor in the exposure of animals to high mycotoxin contents. Further studies are recommended to ensure continued monitoring and reduction of the risk associated with exposure of animals and humans to ZEA.

Zearalenone and Its Emerging Metabolites Promptly Affect the Rumen Microbiota in Holstein Cows Fed a Forage-Rich Diet

The study investigated the short-term effects of a single oral bolus of zearalenone (ZEN) on the rumen microbiota and fermentation patterns in four rumen-cannulated Holstein cows fed a forage diet with daily 2 kg/cow concentrate. During the baseline day, cows received uncontaminated concentrate, followed by ZEN-contaminated concentrate on the second day, and again the uncontaminated concentrate on day three. Free rumen liquid (FRL) and particle-associated rumen liquid (PARL) were collected at different hours post-feeding on all days to analyze the prokaryotic community composition, absolute abundances of bacteria, archaea, protozoa, and anaerobic fungi, as well as short-chain fatty acid (SCFA) profiles. The ZEN reduced the microbial diversity in FRL but not in the PARL fraction. The abundance of protozoa was higher after ZEN exposure in PARL, which may be related to their strong biodegradation capacity that, therefore, promoted protozoal growth. In contrast, α-zearalenol might compromise anaerobic fungi as indicated by reduced abundances in FRL and fairly negative correlations in both fractions. Total SCFA significantly increased in both fractions after ZEN exposure, while the SCFA profile only changed marginally. Concluding, a single ZEN challenge caused changes in the rumen ecosystem soon after intake, including ruminal eukaryotes, that should be the subject of future studies.

Assessment of selected immunological parameters in dairy cows with naturally occurring mycotoxicosis before and after the application of a mycotoxin deactivator

Introduction

Mycotoxins in dairy cows can cause many non-specific symptoms often resulting from immune system overreaction. The study assessed the concentration of selected cytokines and acute phase proteins (APP) in cows with natural mycotoxicosis before and after using a mycotoxin neutraliser. The cytokines were tumour necrosis factor alpha (TNF-α), interleukin 6 (IL-6) and interleukin 10 (IL-10), and the APP were serum amyloid A (SAA) and haptoglobin (Hp).

Material and Methods

The research was carried out on an experimental group (Exp) of 10 herdmate Holstein-Friesian cows with mycotoxicosis. The control group (Con) was 10 healthy cows of the same breed from a different herd. Cows in the Exp group were administered the mycotoxin deactivator Mycofix for three months. Blood was drawn from Exp cows once before administering Mycofix and a second time after three months of its use. Blood was also drawn from Con cows at the same times. Serum levels of TNF-α, IL-6, IL-10, SAA and Hp were assessed using ELISA.

Results

The concentrations of all cytokines and Hp in Exp cows were higher before treatment (P < 0.001) than those in Con cows. After three months of administering Mycofix, the concentrations of TNF-α and IL-6 were significantly lower than their pre-treatment levels (P < 0.001). The concentrations of IL-6, IL-10, and Hp were still significantly higher than those in the Con group (P < 0.001). In cows with mycotoxicosis, simultaneous stimulation of antagonistic processes was noted: a pro-inflammatory process in the upregulation of TNF-α and IL-6, and an anti-inflammatory one in the upregulation of IL-10.

Conclusion

Despite the absorbent’s use and the resolution of clinical symptoms in Exp cows, high levels of IL-10 and Hp and IL-6 were maintained. Assessment of the level of cytokines and APP appears to be a useful and precise tool for the evaluation and application of the appropriate dose of the mycotoxin absorbent or the evaluation of its effectiveness.

Traditional and emerging Fusarium mycotoxins disrupt homeostasis of bovine mammary cells by altering cell permeability and innate immune function

High incidence of traditional and emerging Fusarium mycotoxins in cereal grains and silages can be a potential threat to feed safety and ruminants. Inadequate biodegradation of Fusarium mycotoxins by rumen microflora following ingestion of mycotoxin-contaminated feeds can lead to their circulatory transport to target tissues such as mammary gland. The bovine udder plays a pivotal role in maintaining milk yield and composition, thus, human health. However, toxic effects of Fusarium mycotoxins on bovine mammary gland are rarely studied. In this study, the bovine mammary epithelial cell line was used as an in-vitro model of bovine mammary epithelium to investigate effects of deoxynivalenol (DON), enniatin B (ENB) and beauvericin (BEA) on bovine mammary gland homeostasis. Results indicated that exposure to DON, ENB and BEA for 48 h significantly decreased cell viability in a concentration-dependent manner (P < 0.001). Exposure to DON at 0.39 μmol/L and BEA at 2.5 μmol/L for 48 h also decreased paracellular flux of FITC-40 kDa dextran (P < 0.05), whereas none of the mycotoxins affected transepithelial electrical resistance after 48 h exposure. The qPCR was performed for assessment of expression of gene coding tight junction (TJ) proteins, toll-like receptor 4 (TLR4) and cytokines after 4, 24 and 48 h of exposure. DON, ENB and BEA significantly upregulated the TJ protein zonula occludens-1, whereas markedly downregulated claudin 3 (P < 0.05). Exposure to DON at 1.35 μmol/L for 4 h significantly increased expression of occludin (P < 0.01). DON, ENB and BEA significant downregulated TLR4 (P < 0.05). In contrast, ENB markedly increased expression of cytokines interleukin-6 (IL-6) (P < 0.001), tumor necrosis factor α (TNF-a) (P < 0.05) and transforming growth factor-β (TGF-β) (P < 0.01). BEA significantly upregulated IL- 6 (P < 0.001) and TGF-β (P = 0.01), but downregulated TNF-α (P < 0.001). These results suggest that DON, ENB and BEA can disrupt mammary gland homeostasis by inducing cell death as well as altering its paracellular permeability and expression of genes involved in innate immune function.

Safety and Quality of Milk and Milk Products in Senegal—A Review

Historically, local milk production in Senegal has struggled to keep up with the demands of consumers, so there has been a heavy reliance on imported milk and milk products. More recently, efforts have been made to improve local dairy production by establishing large, organized dairies that collect milk from rural production areas and developing small-scale processing units, such as mini dairies. The local dairy value chain in Senegal consists of (1) informal collection systems where farmers commonly deliver milk directly to dairies; (2) traditional and artisanal processing using simple equipment and techniques; and (3) short local marketing and sale circuits. Most West African dairy sectors are dominated by raw, unpasteurized milk or traditional, spontaneously fermented milk products, such as lait caillé in Senegal, sold through small-scale channels without a cold chain, so the risk of food safety hazards may be increased. Microbiological, chemical, and physical hazards have been found in milk and milk products across West Africa. There is a need to educate milk producers, small-scale processors, and vendors on the importance of refrigerating milk immediately after milking as well as maintaining the cold chain until the milk is heat treated and, subsequently, until the milk is marketed to the consumer. However, without assistance, obtaining the equipment necessary for cold storage and processing of milk can be challenging.

Mixtures of mycotoxins, phytoestrogens and pesticides co-occurring in wet spent brewery grains (BSG) intended for dairy cattle feeding in Austria

Spent brewery grains (BSG) are the main by-product of beer production and are incorporated in rations of food-delivering animals, mainly dairy cows. Like other agricultural commodities, BSG can be contaminated by a broad spectrum of natural and synthetic undesirable substances, which can be hazardous to animal and human health as well as to the environment. The co-occurrence of mycotoxins, phytoestrogens, other fungal and plant secondary metabolites, along with pesticides, was investigated in 21 BSG samples collected in dairy farms in Austria. For this purpose, a validated multi-metabolite liquid chromatography/electrospray ionisation tandem mass spectrometry (LC/ESI-MS/MS) was employed. Metabolites derived from Fusarium, Aspergillus, Alternaria and pesticide residues, were ubiquitous in the samples. Zearalenone (ZEN), T-2 and HT-2 toxins were the only regulated mycotoxin detected, albeit at concentrations below the European guidance values for animal feeds. Ergot alkaloids, Penicillium-derived metabolites, and phytoestrogens had occurrence rates of 90, 48 and 29%, respectively. Penicillium metabolites presented the highest levels among the fungal compounds, indicating contamination during storage. Aflatoxins (AFs), ochratoxins and deoxynivalenol (DON) were not detected. Out of the 16 detected pesticides, two fungicides, ametoctradin (9.5%) and mandipropamid (14.3%) revealed concentrations exceeding their respective maximum residue level (MRL) (0.01 mg kg^-1) for barley in two samples. Although based on European guidance and MRL values the levels of the detected compounds probably do not pose acute risks for cattle, the impact of the long-time exposure to such mixtures of natural and synthetic toxicants on animal health and food safety are unknown and must be elucidated.

Zearalenone Promotes LPS-Induced Oxidative Stress, Endoplasmic Reticulum Stress, and Accelerates Bovine Mammary Epithelial Cell Apoptosis

Both zearalenone (ZEA) and lipopolysaccharide (LPS) can induce oxidative stress, and even apoptosis in bovine mammary epithelial cells (MAC-T), but not much attention has been given to the synergistic effect of ZEA and LPS. In this study, we treated MAC-T cells with different concentrations of LPS (1, 10, 50, and 100 μg/mL) and ZEA (5, 15, and 30 μM) to induce cell damage. Previous results show that MAC-T cell viability decreases with increasing LPS concentration. Meanwhile, 1 µg/mL LPS and ZEA were selected for combined treatment in subsequent studies. It was found that co-treatment with ZEA and LPS increases the accumulation of reactive oxygen species (ROS) and malondialdehyde (MDA), decreases mitochondrial membrane potential (MMP), and superoxide dismutase (SOD), and reduces glutathione (GSH). ZEA and LPS are found to activate endoplasmic reticulum (ER) stress by increasing the expression of glucose-regulated protein 78 kDa (GRP78), activating transcription factor 6 (ATF6) and C/EBP homologous protein (CHOP). It increases cell apoptosis by suppressing the expression of the anti-apoptotic protein B-cell lymphoma-2 (Bcl-2), indicated by up-regulation of Bcl2-associated X protein (Bax) and Cysteinyl aspartate-specific proteinases 3 (caspase-3) expression. The above results suggest that the synergistic effect of ZEA and LPS aggravate cytotoxicity.

Risk factors associated with indicators of dairy cow welfare during the housing period in Irish, spring-calving, hybrid pasture-based systems

In a dairy production system where cows are grazing for a large portion of their lactation, little attention has been afforded to investigating multiple indicators of welfare for risk factors associated with the housing period. Yet regardless of the length of the housing period, cows still experience the positive and negative welfare impacts of both indoor and outdoor environments in a hybrid system. Thus, the objective of this study was to identify risk factors for indicators of dairy cow welfare during the housing period in a spring-calving, hybrid pasture-based system. Herd-level scores for seven indicators of welfare (locomotion, body condition, ocular and nasal discharge, integument damage, tail injury and human avoidance response) were collected from 82 Irish dairy farms during the housing period (October - February). Data were analysed using multiple beta regression or zero-inflated beta regression to identify associations between these welfare indicators and measured herd-level housing, resource and management factors. Thirty-six unique risk factors were associated with one or more welfare indicators (P < 0.05). Analyses identified two risk factors for body condition < 3.0 and four for body condition > 3.5, the target range during the housing period. Four risk factors were identified for each of ocular discharge, nasal discharge and avoidance response of > 1 m from human approach. Six risk factors each were associated with the proportion of lame cows and integument damage to the head-neck-back or hindquarter regions. The greatest number of risk factors, 12, were associated with tail injury (broken, lacerated or incomplete tails). Risk factors associated with multiple indicators of welfare were cow comfort index (tail lacerations and hindquarter integument damage), cubicle width (broken and incomplete tails), shed floor slipperiness (lameness and head-neck-back integument damage), shed light-level (tail lacerations, avoidance response and below target body condition), shed passage width (broken tails and head-neck-back integument damage) and presence (incomplete tails) or absence (broken tails) of a collecting yard backing gate. With the large number of risk factors associated with tail injury, continued research is necessary to identify causes and determine prevention methods to contribute to improved overall welfare of dairy cows. Housing features meeting recommended guidelines from the literature were frequently associated with greater negative indicators of welfare. In light of this, housing guidelines may benefit from regular re-evaluation to ensure facilities meet the welfare needs of cows during the housing period.

Cocktails of Mycotoxins, Phytoestrogens, and Other Secondary Metabolites in Diets of Dairy Cows in Austria: Inferences from Diet Composition and Geo-Climatic Factors

Dairy production is a pivotal economic sector of Austrian and European agriculture. Dietary toxins and endocrine disruptors of natural origin such as mycotoxins and phytoestrogens can affect animal health, reproduction, and productivity. This study characterized the profile of a wide spectrum of fungal, plant, and unspecific secondary metabolites, including regulated, emerging, and modified mycotoxins, phytoestrogens, and cyanogenic glucosides, in complete diets of lactating cows from 100 Austrian dairy farms. To achieve this, a validated multi-metabolite liquid chromatography/electrospray ionization−tandem mass spectrometric (LC/ESI−MS/MS) method was employed, detecting 155 of >800 tested metabolites. Additionally, the most influential dietary and geo-climatic factors related to the dietary mycotoxin contamination of Austrian dairy cattle were recognized. We evidenced that the diets of Austrian dairy cows presented ubiquitous contamination with mixtures of mycotoxins and phytoestrogens. Metabolites derived from Fusarium spp. presented the highest concentrations, were the most recurrent, and had the highest diversity among the detected fungal compounds. Zearalenone, deoxynivalenol, and fumonisin B1 were the most frequently occurring mycotoxins considered in the EU legislation, with detection frequencies >70%. Among the investigated dietary factors, inclusion of maize silage (MS) and straw in the diets was the most influential factor in contamination with Fusarium-derived and other fungal toxins and metabolites, and temperature was the most influential among the geo-climatic factors.

Adverse Effects of Fusarium Toxins in Ruminants: A Review of In Vivo and In Vitro Studies

With an increased knowledge of the mechanism of action of Fusarium mycotoxins, the concept that these substances are deleterious only for monogastric species is obsolete. Indeed, most mycotoxins can be converted into less toxic compounds by the rumen microflora from healthy animals. However, mycotoxin absorption and its conversion to more toxic metabolites, as well as their impact on the immune response and subsequently animal welfare, reproductive function, and milk quality during chronic exposure should not be neglected. Among the Fusarium mycotoxins, the most studied are deoxynivalenol (DON), zearalenone (ZEN), and fumonisins from the B class (FBs). It is remarkable that there is a paucity of in vivo research, with a low number of studies on nutrient digestibility and rumen function. Most of the in vitro studies are related to the reproductive function or are restricted to rumen incubation. When evaluating the production performance, milk yield is used as an evaluated parameter, but its quality for cheese production is often overlooked. In the present review, we summarize the most recent findings regarding the adverse effects of these mycotoxins with special attention to dairy cattle.

Effects of grape phenolics, myricetin and piceatannol, on bovine granulosa and theca cell proliferation and steroid production in vitro

Myricetin (a flavonol) and piceatannol (a stilbenoid) are naturally occurring phenolic compounds in red wine with cardio-protective and anti-carcinogenic effects, but their potential reproductive effects have not been investigated. Thus, the present study was designed to determine if myricetin and piceatannol can directly affect ovarian function using bovine granulosa cells (GC) and theca cells (TC) as in vitro model systems to evaluate effects on cell proliferation and steroid production. In Experiment 1 and 2, myricetin and piceatannol at 30 μM blocked insulin-like growth factor 1 (IGF1)-induced progesterone production by GC without affecting GC numbers. In contrast, myricetin stimulated IGF1-induced estradiol production, whereas piceatannol at 30 μM inhibited IGF1-induced estradiol production by 90% in GC. In Experiment 3 and 4, TC androstenedione and progesterone production and TC proliferation was inhibited by myricetin and piceatannol at 30 μM. In Experiment 5, piceatannol (30 μM) reduced the Fusarium mycotoxin, beauvericin (6 μM)-induced inhibition on progesterone production and cell proliferation. Myricetin (30 μM) reduced the inhibitory effect of beauvericin on estradiol but not progesterone production or cell proliferation. In conclusion, the red wine phenols, myricetin and piceatannol, directly affected GC and TC steroidogenesis, and were able to reduce some of the inhibitory effects of beauvericin on GC function.

Diversity of Toxigenic Fungi in Livestock and Poultry Feedstuffs

The purpose of this study was to discover how abundant toxigenic fungi and mycotoxins are in animal feedstuff samples. A total of ninety samples representing various types of animal feedstuff samples were collected from ninety sites in Egypt. Isolation, identification, and determination of mycotoxins (aflatoxins B1, B2, G1, G2, and ochratoxin A) were performed. The results revealed that 79 (87.77%) of the samples were contaminated with fungi, and 1.1 × 10⁵ CFU/g were recovered, including 41 fungal species belonging to 18 genera, such as Zygomycota, which was represented by three species (7.31% of the total species number), teleomorphic Ascomycota (10 species, 24.39%), and anamorphic Ascomycota (28 species, 69.29%). When taxonomically investigated, these species were categorized into 2 phyla, 4 classes, 6 orders, and 12 families (one of them with an uncertain position). Moreover, the genus Aspergillus exhibited 16 species (39.02%). Notably, site no. 6 showed the highest Margalef species richness index at 10.87 followed by site no. 4, while the Shannon diversity index (H) of the recovered taxa was 2.20. Based on the frequency of occurrence, Aspergillus flavus recorded the highest percentage (65.56%) followed by A. niger (50%) and Penicillium chrysogenum (40%). Genus Aspergillus was recorded in 75 samples (88.33%), while Penicillium appeared only in 43 samples, accounting for 47.77% out of 90 samples. The High-performance liquid chromatography (HPLC) analysis showed that aflatoxin B1 (AFB1) was recorded in two animal feedstuff samples at a ratio of 0.851 and 1.363 µg/kg, While AFB2 was discovered in only one animal feedstuff sample at a ratio of 0.479 g/kg. The aflatoxins levels in the positive samples (AFB1 and AFB2) Beef cattle sample components were below the permissible limit for animal feedstuff which is (20 g/kg). Although aflatoxins were found in certain samples, the amounts were much below the maximum residue limits (MRLs) defined by the international authorities or Egyptian guidelines. toxigenic fungi found in contaminated animal feed samples pose a major threat to animal and poultry health, productivity, and even human health. Therefore, periodic monitoring is an excellent way to keep track of their existence and mitigate their hazards.

Nutritional impact of mycotoxins in food animal production and strategies for mitigation

Mycotoxins are toxic secondary metabolites produced by filamentous fungi that are commonly detected as natural contaminants in agricultural commodities worldwide. Mycotoxin exposure can lead to mycotoxicosis in both animals and humans when found in animal feeds and food products, and at lower concentrations can affect animal performance by disrupting nutrient digestion, absorption, metabolism, and animal physiology. Thus, mycotoxin contamination of animal feeds represents a significant issue to the livestock industry and is a health threat to food animals. Since prevention of mycotoxin formation is difficult to undertake to avoid contamination, mitigation strategies are needed. This review explores how the mycotoxins aflatoxins, deoxynivalenol, zearalenone, fumonisins and ochratoxin A impose nutritional and metabolic effects on food animals and summarizes mitigation strategies to reduce the risk of mycotoxicity.

Short-term exposure to the mycotoxins zearalenone or fumonisins affects rumen fermentation and microbiota, and health variables in cattle

Zearalenone (ZEN) and fumonisins (FUM) jeopardize fertility and health in cattle; yet, their toxigenic effects on rumen health and microbiota, both being crucial for animal health, are not clarified. This study determined the effects of a short-term exposure to ZEN or FUM on the rumen ecosystem, and further evaluated acute implications on health parameters. Six cows were fed a basal diet with 40% grain (dry matter basis) and exposed to either 5 mg of ZEN or 20 mg of FUM daily for two consecutive days each, separated by a 7-days washout period. The exposure to ZEN or FUM led to a reduction of Lachnospiraceae and Prevotellaceae in the rumen. Similarly, ZEN lowered the ruminal pH and total short-chain fatty acid concentration, despite increased rumination activity of the cows. Fumonisins increased the number of observed features and significantly impacted β-diversity structure and metagenome predicted function. At the systemic level, FUM exposure suggested an immediate hepatotoxic effect, as evidenced by increased liver enzyme concentrations, which were accompanied by altered heart and respiratory rates. Similarly, ZEN increased the body temperature up to a mild fever. Concluding, short-term exposure to ZEN and FUM can harm the rumen ecosystem and acutely impair systemic health.

Fungal species and mycotoxins in mouldy spots of grass and maize silages in Austria

Fungi and mycotoxins in silage can have detrimental consequences for both cattle and human health. This pilot study identified, via the routinary direct plating method, the dominant cultivable fungi in mouldy grass silages (GS) (n = 19) and maize silages (MS) (n = 28) from Austria. The profiles of regulated, modified, and emerging mycotoxins together with other fungal metabolites were analysed via LC-(ESI)MS/MS. Penicillium roqueforti, Saccharomyces spp., Geotrichum candidum, Aspergillus fumigatus and Monascus ruber were the most frequent fungal organisms identified. Other species including Mucor circinelloides, Fusarium spp. and Paecilomyces niveus were detected at lower frequencies. The presence of complex mixtures of toxic and potentially toxic compounds was evidenced by high levels and occurrences (≥ 50%) of Penicillium-produced compounds such as mycophenolic acid (MPA), roquefortines (ROCs), andrastins (ANDs) and marcfortine A. Mouldy silages contained toxins commonly produced by genus Fusarium (e.g. zearalenone (ZEN) and trichothecenes), Alternaria (like tenuazonic acid (TeA) and alternariol (AHO)) and Aspergillus (such as sterigmatocystin (STC)). Compared to those in GS, mouldy spots in MS presented significantly higher fungal counts and more diverse toxin profiles, in addition to superior levels of Fusarium spp., Penicillium spp. and total fungal metabolites. Generally, no correlation between mould counts and corresponding metabolites was detected, except for the counts of P. roqueforti, which were positively correlated with Penicillium spp. metabolites in mouldy MS. This study represents a first assessment of the fungal diversity in mouldy silage in Austria and highlights its potential role as a substantial contributor to contamination with complex mycotoxin mixtures in cattle diets.

Association between aflatoxin M1 excretion in milk and indicators of rumen fermentation in bovines

Aflatoxins and its metabolites negatively impact the ruminant health and production. The present cross-sectional study was aimed to determine the effect of aflatoxins on rumen fermentation by deducing the correlation between the aflatoxin M1 (AFM1) excretion in milk and indicators of rumen fermentation in bovines. The indicators of rumen fermentation were taken into account and correlated with AFM1 concentration in milk of 120 bovines (cattle (n = 82) and buffalo (n = 38)). The AFM1 in milk samples (n = 120) was quantified by ELISA kit. The correlation analysis revealed that with increase in excretion of AFM1 in milk, the pH (r = 0.38), methylene blue reduction time (MBRT) (r = 0.43), sedimentation activity time (SAT) (r = 0.31) and ammonia nitrogen content (r = 0.34) of rumen liquor increase, whereas the total volatile fatty acid (TVFA) content (r =  - 0.25), total bacterial count (TBC) (r =  - 0.43) and total protozoal count (TPC) (r =  - 0.14) of rumen liquor decrease. The results of the present study suggest that the presence of aflatoxins in rumen could have negative effect on the process of rumen fermentation. Therefore, the prevention of primary entry point(s) of AFB1 through the feed of bovines is important for the animal health as well as public health.

Practical Application of Urinary Zearalenone Monitoring System for Feed Hygiene Management of a Japanese Black Cattle Breeding Herd—The Relationship between Monthly Anti-Müllerian Hormone and Serum Amyloid A Concentrations

This study addresses an advantageous application of a urinary zearalenone (ZEN) monitoring system not only for surveillance of ZEN exposure at the production site of breeding cows but also for follow-up monitoring after improvement of feeds provided to the herd. As biomarkers of effect, serum levels of the anti-Müllerian hormone (AMH) and serum amyloid A (SAA) concentrations were used. Based on the results of urinary ZEN measurement, two cows from one herd had urinary ZEN concentrations which were two orders of magnitude higher (ZEN: 1.34 mg/kg, sterigmatocystin (STC): 0.08 mg/kg in roughages) than the levels of all cows from three other herds (ZEN: not detected, STC: not detected in roughages). For the follow-up monitoring of the herd with positive ZEN and STC exposure, urine, blood, and roughage samples were collected from five cows monthly for one year. A monitoring series in the breeding cattle herd indicated that feed concentrations were not necessarily reflected in urinary concentrations; urinary monitoring assay by ELISA may be a simple and accurate method that reflects the exposure/absorption of ZEN. Additionally, although the ZEN exposure level appeared not to be critical compared with the Japanese ZEN limitation in dietary feeds, a negative regression trend between the ZEN and AMH concentrations was observed, indicating that only at extremely universal mycotoxin exposure levels, ZEN exposure may affect the number of antral follicles in cattle. A negative regression trend between the ZEN and SAA concentrations could also be demonstrated, possibly indicating the innate immune suppression caused by low-level chronic ZEN exposure. Finally, significant differences (p = 0.0487) in calving intervals between pre-ZEN monitoring (mean ± SEM: 439.0 ± 41.2) and post-ZEN monitoring (349.9 ± 6.9) periods were observed in the monitored five cows. These preliminary results indicate that the urinary ZEN monitoring system may be a useful practical tool not only for detecting contaminated herds under field conditions but also provides an initial look at the effects of long-term chronic ZEN/STC (or other co-existing mycotoxins) exposure on herd productivity and fertility.

A Case Study Using Accelerometers to Identify Illness in Ewes Following Unintentional Exposure to Mold-Contaminated Feed

Sensor technologies can identify modified animal activity indicating changes in health status. This study investigated sheep behavior before and after illness caused by mold-contaminated feed using tri-axial accelerometers. Ten ewes were fitted with HerdDogg biometric accelerometers. Five ewes were concurrently fitted with Axivity AX3 accelerometers. The flock was exposed to mold-contaminated feed following an unexpected ration change, and observed symptomatic ewes were treated with a veterinarian-directed protocol. Accelerometer data were evaluated 4 days before exposure (d −4 to −1); the day of ration change (d 0); and 4 days post exposure (d 1 to 4). Herddogg activity index correlated to the variability of minimum and standard deviation of motion intensity monitored by the Axivity accelerometer. Herddogg activity index was lower (p < 0.05) during the mornings (0800 to 1100 h) of days 2 to 4 and the evening of day 1 than days −4 to 0. Symptomatic ewes had lower activity levels in the morning and higher levels at night. After accounting for symptoms, activity levels during days 1 to 4 were lower (p < 0.05) than days −4 to 0 the morning after exposure. Results suggest real-time or near-real time accelerometers have potential to detect illness in ewes.

Co-Occurrence of 35 Mycotoxins: A Seven-Year Survey of Corn Grain and Corn Silage in the United States

Mycotoxins contaminate crops worldwide and play a role in animal health and performance. Multiple mycotoxins may co-occur which may increase the impact on the animal. To assess the multiple mycotoxin profile of corn (Zea mays), we conducted a 7-year survey of new crop corn grain and silage in the United States. A total of 711 grain and 1117 silage samples were collected between 2013 and 2019 and analyzed for the simultaneous presence of 35 mycotoxins using ultra-performance liquid chromatography–tandem mass spectrometry. The measured mean number of mycotoxins per sample were 4.8 (grain) and 5.2 (silage), ranging from 0 to 13. Fusaric acid (FA) was most frequently detected in 78.1 and 93.8% of grains and silages, respectively, followed by deoxynivalenol (DON) in 75.7 and 88.2% of samples. Fumonisin B1 (FB1), fumonisin B2 and 15-acetyl-deoxynivalenol (15ADON) followed. The greatest (p < 0.05) co-occurrence was between FA and DON in 59.1% of grains and 82.7% of silages, followed by FA with FB1, DON with 15ADON, and FA with 15ADON. Although many samples had lower mycotoxin concentrations, 1.6% (grain) and 7.9% (silage) of tested samples had DON ≥ 5000 µg/kg. Fumonisins were detected ≥ 10,000 µg/kg in 9.6 and 3.9% of grain and silage samples, respectively. Concentrations in grain varied by year for eight mycotoxin groups (p < 0.05), while all 10 groups showed yearly variations in silage. Our survey suggest that multiple mycotoxins frequently co-occur in corn grain and silage in the United States, and some of the more prevalent mycotoxins are those that may not be routinely analyzed (i.e., FA and 15ADON). Assessment of multiple mycotoxins should be considered when developing management programs.

Mycotoxins, Phytoestrogens and Other Secondary Metabolites in Austrian Pastures: Occurrences, Contamination Levels and Implications of Geo-Climatic Factors

Pastures are key feed sources for dairy production and can be contaminated with several secondary metabolites from fungi and plants with toxic or endocrine-disrupting activities, which possess a risk for the health, reproduction and performance of cattle. This exploratory study aimed to determine the co-occurrences and concentrations of a wide range of mycotoxins, phytoestrogens and other secondary metabolites in grazing pastures. Representative samples of pastures were collected from 18 Austrian dairy farms (one sample per farm) between April to October 2019. After sample preparation (drying and milling) the pastures were subjected to multi-metabolite analysis using LC-MS/MS. In total, 68 metabolites were detected, including regulated zearalenone and deoxynivalenol (range: 2.16-138 and 107-505 μg/kg on a dry matter (DM) basis, respectively), modified (3-deoxynivalenol-glucoside, HT-2-glucoside) and emerging Fusarium mycotoxins (e.g., enniatins), ergot alkaloids and Alternaria metabolites along with phytoestrogens and other metabolites. Aflatoxins, fumonisins, T-2 toxin, HT-2 toxin and ochratoxins were not detected. Of the geo-climatic factors and botanical diversity investigated, the environment temperature (average of 2 pre-sampling months and the sampling month) was the most influential factor. The number of fungal metabolites linearly increased with increasing temperatures and temperatures exceeding 15 °C triggered an exponential increment in the concentrations of Fusarium and Alternaria metabolites and ergot alkaloids. In conclusion, even though the levels of regulated mycotoxins detected were below the EU guidance levels, the long-term exposure along with co-occurrence with modified and emerging mycotoxins might be an underestimated risk for grazing and forage-fed livestock. The one-year preliminary data points out a dominant effect of environmental temperature in the diversity and contamination level of fungal metabolites in pastures.

Mitigation of sterigmatocystin exposure in cattle by difructose anhydride III feed supplementation and detection of urinary sterigmatocystin and serum amyloid A concentrations

We evaluated the effects of supplementing cattle feed with difructose anhydride III (DFA III) by measuring urinary sterigmatocystin (STC) concentrations using 20 Japanese Black cattle aged 9–10 months from one herd. DFA III was supplemented for 2 weeks for 10 animals, and non-treated animals served as controls. The natural STC concentration in the dietary feed was 0.06 mgkg-1 (mixture of roughage and concentrate) at the beginning of the study (Day 0). The urine STC concentration was measured using liquid chromatography with tandem mass spectrometry 1 d prior to DFA III administration, 9 and 14 d thereafter, and 9 d following supplementation cessation, concomitant with the measurement of serum amyloid A (SAA). The number of heifers in which STC was detected in the urine was low (10 %) in the DFA III group compared to that (60 %) in the control group on Day 9. After 9 d following supplementation cessation (Day 23), STC concentrations were significantly lower (P=0.032) in the DFA III group than in the control group, although there was no difference in the number of heifers in which urinary STC was detected or in SAA concentrations between the two groups. Our findings demonstrate the effect of DFA III on reducing the urinary concentration of STC in Japanese Black cattle.

Aflatoxin in Dairy Cows: Toxicity, Occurrence in Feedstuffs and Milk and Dietary Mitigation Strategies

Aflatoxins are poisonous carcinogens produced by fungi, mainly Aspergillus flavus and Aspergillus parasiticus. Aflatoxins can contaminate a variety of livestock feeds and cause enormous economic losses, estimated at between US$52.1 and US$1.68 billion annually for the U.S. corn industry alone. In addition, aflatoxin can be transferred from the diet to the milk of cows as aflatoxin M1 (AFM1), posing a significant human health hazard. In dairy cows, sheep and goats, chronic exposure to dietary aflatoxin can reduce milk production, impair reproduction and liver function, compromise immune function, and increase susceptibility to diseases; hence, strategies to lower aflatoxin contamination of feeds and to prevent or reduce the transfer of the toxin to milk are required for safeguarding animal and human health and improving the safety of dairy products and profitability of the dairy industry. This article provides an overview of the toxicity of aflatoxin to ruminant livestock, its occurrence in livestock feeds, and the effectiveness of different strategies for preventing and mitigating aflatoxin contamination of feeds.

Multianalyte method for the determination of regulated, emerging and modified mycotoxins in milk: QuEChERS extraction followed by UHPLC-MS/MS analysis

A simple method for the quantification of 40 mycotoxins in milk was developed. This method is based on a QuEChERS extraction followed by the ultra-high liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) detection, and allows the simultaneous analysis of regulated, emerging, and modified mycotoxins. A sample treatment procedure was optimized to include a concentration step for the analysis of some compounds such as aflatoxin M₁. The method was in-house validated in terms of limits of detection (LODs), limits of quantification (LOQs), linearity, recoveries, and precision. LOQs lower than 10 ng/mL were obtained, and recoveries ranged from 61% to 120% with a precision, expressed as the relative standard deviation, lower than 15%. Therefore, acceptable performance characteristics were obtained fulfilling European regulations. The method was successfully applied for the quantification of mycotoxins in raw milk. It can be highlighted high occurrence of beauvericin and enniatins were found in low amounts.

Concentrations of zearalenone and its metabolites in female wild boars from woodlands and farmlands

As a valuable food base and safe shelter, large agricultural fields create favourable living conditions for wild boars for most of the year. The occurrence of mould in these fields, causing hormonal disturbances, may lead to a lower age of sexual maturity and a prolonged breeding season, and therefore, the population growth in farmlands can be markedly higher than that in extensive woodlands. This study was initiated because of reproductive cycle disturbances in wild boar populations, which were presumably linked with habitat and food types, especially rotten maize. To determine if the major sources of zearalenone (ZEN) in female wild boars are maize cobs infected with mycotoxins, we compared the concentrations of ZEN and its metabolites in organs, tissues and body fluids of wild boars hunted in extensive maize fields and in extensive woodlands where no large maize fields were located within a distance of several km. Samples of blood, bile, liver, kidneys, muscles, urine, stomach and colon contents as well as ovaries from young female wild boars (40-60 kg) were collected in 2011-2014 and prepared for liquid chromatography tandem mass spectrometry (HPLC-MS/MS). The results showed that ZEN was present in most of the samples, from both farmlands and woodlands, but its concentration within individual types of the analysed body fluids or tissues differed depending mainly on habitat type. In nearly all the analysed cases, higher concentrations of ZEN and its derivatives were detected in the samples collected from wild boars in farmlands, suggesting that wild boars living and feeding in extensive maize fields take in markedly higher amounts of mycoestrogens.

Field Monitoring of Aflatoxins in Feed and Milk of High-Yielding Dairy Cows under Two Feeding Systems

Aflatoxin M1 (AFM1) is a hydroxylated metabolite of aflatoxin B1 (AFB1) that can be excreted in milk of cows after consuming contaminated feed. The aim of this study consisted of a field monitoring to assess the contamination levels of AFB1 in 60 feed samples from two feeding systems for high-yielding dairy cows and of AFM1 in the corresponding raw milk samples. The aflatoxins were analyzed by in-house validated methods based on high-performance liquid chromatography (HPLC) with fluorescence detection. AFB1 was detected in 55% of feed samples (mean 0.61 μg/kg, with 2 samples exceeding the European Union (EU) maximum level set at 5 μg/kg), with greater incidence and concentration in compound feed than in unifeed rations (p < 0.05). AFM1 was detected in 38.3% milk samples (mean 12.6 ng/kg, with 5 samples exceeding the EU maximum level set at 50 ng/kg), with a higher occurrence in milk of cows fed compound feed, as well as in spring milk compared to that produced in winter. The overall transfer ratio of aflatoxins from feed to milk was 3.22%, being higher in cows fed with compound feed and in spring milkings. In a selection of positive matched samples (n = 22), the ratio AFM1/AFB1 exceeded the European Food Safety Authority (EFSA) estimated 6% threshold for high-yielding dairy cows.

The Present Role and New Potentials of Anaerobic Fungi in Ruminant Nutrition

The ruminal microbiota allows ruminants to utilize fibrous feeds and is in the limelight of ruminant nutrition research for many years. However, the overwhelming majority of investigations have focused on bacteria, whereas anaerobic fungi (AF) have been widely neglected by ruminant nutritionists. Anaerobic fungi are not only crucial fiber degraders but also important nutrient sources for the host. This review summarizes the current findings on AF and, most importantly, discusses their new application potentials in modern ruminant nutrition. Available data suggest AF can be applied as direct-fed microbials to enhance ruminal fiber degradation, which is indeed of interest for high-yielding dairy cows that often show depressed ruminal fibrolysis in response to high-grain feeding. Moreover, these microorganisms have relevance for the nutrient supply and reduction of methane emissions. However, to reach AF-related improvements in ruminal fiber breakdown and animal performance, obstacles in large-scale AF cultivation and applicable administration options need to be overcome. At feedstuff level, silage production may benefit from the application of fungal enzymes that cleave lignocellulosic structures and consequently enable higher energy exploitation from forages in the rumen. Concluding, AF hold several potentials in improving ruminant feeding and future research efforts are called for to harness these potentials.

Viability of the use of mycotoxin adsorbent in the finishing of Texel lambs in confinement

The objective of the present study was to evaluate the viability of a mycotoxin adsorbent based on beta-glucans from cell walls of Saccharomyces cerevisiae and bentonites in the diets of confined lambs of the Texel breed. Twenty-four lambs (12 males and 12 females) with an average weight of 18.6 kg ± 1.6 were divided into two groups: treated (with adsorbent) and control. The animal diets contained the mycotoxins aflatoxin B1, fumonisin B1 and B2, zearalenone, and deoxynivalenol in concentrations within guidance levels. The animals were slaughtered with body weight of approximately 26.4 kg. The performance and carcass variables of the lambs were evaluated. The daily weight gain was higher in the treated group (216.24 g) than in the control group (185.90 g). The averages for loin eye area, subcutaneous fat thickness, and marbling were 13.93 cm², 2.66 mm, and 3.20 in the treated group and 12.16 cm², 2.6 mm, and 3.25 in the control group, respectively. The true, hot, and cold carcass yield, and the carcass cooling losses did not differ between groups. The carcasses were similar in conformation and fat finishing degree, with averages of 3.95 and 3.83, respectively. To the best of our knowledge, this is the first study to evaluate the effect of a mycotoxin additive in the diet of finishing lambs. The use of mycotoxin adsorbent in confined lambs was feasible, and its use resulted in greater daily weight gain in lambs and average net profit.