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Abstract: Theories suggest that incorporating alfalfa (Medicago sativa L.; Alf) or birdsfoot trefoil (Lotus corniculatus L.; BFT) into endophyte‐infected tall fescue (Festuca arundinaceas Schreb.; E+TF) pasturelands may improve livestock production. We investigated how planting configuration might influence plant secondary metabolites (PSM) and nitrogen concentration in these forages. Total nitrogen (N), in addition to condensed tannins (CT), saponins and ergovaline (EV), was compared in BFT, Alf and E+TF, respectively, when forages grew in monocultures and all possible two‐way “mixtures” using a block design with repeated measures in three blocks. Ergovaline (p < .01) and N (p < .001) concentrations in E+TF were greater when growing adjacent to legumes than when growing in monoculture, and N and EV concentrations in E+TF were positively correlated (r = .51; p = .001). No differences in saponins or CT were found when Alf or BFT grew in monoculture or in two‐way mixtures (p > .10). We conducted an in vitro trial to determine whether CT or saponins isolated from BFT and Alf, respectively, would bind to EV in water. Ergovaline bound to saponins to a greater extent (39%; SE = 0.25) than CT (5.1%; SE = 5.13; p < .05). Because EV was lower in E+TF monocultures than in E+TF–legume mixtures, and because CT and saponins may form complexes with EV which may alleviate fescue toxicosis, animals may benefit from systems which allow them to graze monoculture patches of E+TF and Alf or BFT rather than grass–legume mixtures. [ABSTRACT FROM AUTHOR]

The aim of this study was to verify the carryover of aflatoxin B1 from feed to lambari fish. Aflatoxins (AF) were incorporated into feed, checking the levels by HPLC. Treatments were: Control, feed without toxin; A, feed + 10 µg AFB1 kg–1; B, feed + 20 µg AFB1 kg–1; and C, feed + 50 µg AFB1 kg–1. Juveniles of lambari fish were placed in 12 aquariums at a density of 50 fish/m2. Fish were fed twice a day with extruded feed, at 5% of animal biomass. The unit sample was constituted by a pool of 10 fish. AFs B1, B2, G1, G2 and M1 were quantified by HPLC in fish muscle and liver after 30, 60, 90 and 120 days of experiment. There was accumulation of AFs is fish liver and muscle, mainly after 90 days. Fish from treatment C had higher levels of AFB1 in muscle when compared with the others, and AFB1 in muscle at 120 days was similar to the levels in feed. Therefore, when lambari fish is exposed on a daily and long-term basis to AFs in feed, the regulation limits for AFs in animal feed do not guarantee safety for consumers. [ABSTRACT FROM AUTHOR]

Aflatoxin B1 adsorption by the concentrate of bentonite clay - montmorillonite and the natural zeolite - clinoptilolite and was investigated at the initial toxin concentration 4 ppm, with different amonunts of solid phase in suspension (10, 5, 2 and 1 mg/10 mL) and different pH values - 3, 7 and 9. Results indicated that for both minerals, decreasing the amount of solid phase in suspension, decrease the amount of active sites relevant for adsorption of aflatoxin B1. Thus, for concentrate of montnorillonite, at the lowest level of solid phase in suspension (1 mg/10 mL), aflatoxin B1 adsorption indexes were 97% at pH 3, 88% at pH 7 and 82% at pH 9, while for the natural zeolite, adsorption of toxin was 9% at pH 3 and 7% at pH 7 and 9. Since inorganic cations in minerals are mainly responsible for aflatoxin B1 adsorption, even the natural zeolite - clinoptilite has much higher cation exchange capacity (the content of inorganic exchangeable cations) compared to the concentrate of montmorillonite, adsorption of aflatoxin B1 by this mineral is much lower. Comparing the molecular dimensions of aflatoxin B1 molecule with the dimension of channels of clinoptilolite and interlamellar space of montmorillonite it is obvious that this toxin is adsorbed only at the external surface of clinoptilolite while in the montmorillonite all active sites are equally available for its adsorption. Thus, the concentrate of montmorillonite posess by higher adsorption capacity for aflatoxin B1. Results presented in this paper confirmed the fact the differences in the structure of minerals led to their different efficiency for adsorption of aflatoxin B1. Mineralogical and chemical composition, determination of cation exchange capacity, etc., are very important parameters influencing the effectiveness of minerals as aflatoxin B1 adsorbents. [Projekat Ministarstva nauke Republike Srbije, br. 451-03-2802-IP Tip1/142, br. 172018 i br. 34013]

The objective was to investigate effects of Toxy-Nil (TN) or Unike Plus (UP) on gene expression profiles of blood leukocytes and milk somatic cells (MSC) in dairy cows challenged with dietary aflatoxin B1 (AFB1). Sixteen mid-lactation Holstein cows were assigned to receive one of the following treatments: 1) 2.8 mg of AFB1/cow/day (positive control, PC); 2) 2.8 mg of AFB1 + 100 g of TN/cow/day; 3) 2.8 mg of AFB1 + 100 g of UP/cow/day; or 4) no AFB1 and no adsorbents (negative control, NC). Treatments were administered for 7 days by top-dressing onto a standard TMR diet. Feed and water were available ad libitum throughout the trial. Blood and milk samples were obtained on day 7. Subsequently, mRNA from blood leukocytes and MSC were isolated and sequenced. Genes were considered differentially expressed (DE) when P < 0.001 and FDR ≤ 0.10. There were few differences in gene expression of blood leukocytes. No DE genes were observed when comparing cows not fed AFB1 to those that were fed AFB1 (NC vs average of PC/TN/UP). Comparing cows fed AFB1 alone to cows also receiving adsorbents (PC vs average of TN/UP) revealed one downregulated gene, which was related to mitotic processes and five upregulated genes, which related to nitric oxide generation, signaling, and platelet activation. Comparing TN to UP revealed downregulation of two genes related to platelet activation and iron ion and oxygen binding. In MSC, numerous changes in gene expression were observed. Three annotated genes were DE between NC and TN/UP. No genes were DE between adsorbent treatments (TN vs UP). However, comparing cows not fed AFB1 to those fed AFB1 alone (NC vs PC) revealed 120 DE genes, and 70 genes were DE between cows fed AFB1 without or with adsorbents (PC vs TN/UP). Of those DE genes, 49 were common to the comparisons PC vs NC and PC vs TN/UP. These genes represented functional clusters including glycoproteins and milk proteins, secretion, signaling, protein binding, transporter activity, and response to steroid hormones. Protein domains found to be differentially expressed included a- and b-caseins. Furthermore, approximately 20% of the common DE genes in MSC were mammary gland-specific. In summary, daily feeding of 2.8 mg of aflatoxin B1 to lactating dairy cows resulted in few DE genes in blood leukocytes, but elicited numerous changes in gene expression in milk somatic cells, many of which were modulated in cows fed TN or UP. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the efficacy of two adsorbents, a raw bentonite clay (RC) and a concentrated bentonite clay (CC), in ameliorating the toxic effects of aflatoxin B1 (AFB1). Results of the in vitro study (pH 3.0) indicated the CC adsorbed more AFB1 than RC (93.39 mg/g vs. 79.30 mg/g) suggesting that CC may be more effective than RC in reducing the toxic effects of AFB1. One hundred and eighty day-old straight run broiler chicks were assigned to 6 replicate pens of 5 chicks each and assigned to 6 dietary treatments from hatch to day 21. Dietary treatments included: 1) basal diet (BD) containing no AFB1 or adsorbents; 2) BD plus 0.50% RC; 3) BD plus 0.50% CC; 4) BD plus 2.0 mg AFB1/kg; 5) BD plus 2.0 mg AFB1/kg plus 0.50% RC; and 6) BD plus 2.0 mg AFB1/kg plus 0.50% CC. Dietary AFB1 concentrations were confirmed by analysis and diets were screened for other mycotoxins prior to the start of the experiment. The addition of AFB1 to the feed reduced (P < 0.05) growth performance and increased (P < 0.05) relative liver weight (RLW) and kidney weight (RKW) of chicks fed AFB1 compared to control chicks on day 21. These changes were ameliorated (P < 0.05) by the addition of RC and CC to the AFB1 diet. Mild to moderate lesions of aflatoxicosis (2.25) were observed in chicks fed AFB1 alone on day 21. The addition of both RC and CC to the AFB1 diet decreased (P < 0.05) but did not prevent liver lesions (0.92 and 1.42, respectively). Results indicate that both RC and CC were effective in reducing the toxic effects of AFB1, however the cost of processing of CC would make the RC a more economical product for reducing the effects of AFB1 in young broiler chicks. [ABSTRACT FROM AUTHOR]

The objective was to investigate effects of Toxy-Nil (TN) or Unike Plus (UP) on gene expression profiles of blood leukocytes and milk somatic cells (MSC) in dairy cows challenged with dietary aflatoxin B1 (AFB1). Sixteen mid-lactation Holstein cows were assigned to receive one of the following treatments: 1) 2.8 mg of AFB1/cow/day (positive control, PC); 2) 2.8 mg of AFB1 + 100 g of TN/cow/day; 3) 2.8 mg of AFB1 + 100 g of UP/cow/day; or 4) no AFB1 and no adsorbents (negative control, NC). Treatments were administered for 7 days by top-dressing onto a standard TMR diet. Feed and water were available ad libitum throughout the trial. Blood and milk samples were obtained on day 7. Subsequently, mRNA from blood leukocytes and MSC were isolated and sequenced. Genes were considered differentially expressed (DE) when P < 0.001 and FDR ≤ 0.10. There were few differences in gene expression of blood leukocytes. No DE genes were observed when comparing cows not fed AFB1 to those that were fed AFB1 (NC vs average of PC/TN/UP). Comparing cows fed AFB1 alone to cows also receiving adsorbents (PC vs average of TN/UP) revealed one downregulated gene, which was related to mitotic processes and five upregulated genes, which related to nitric oxide generation, signaling, and platelet activation. Comparing TN to UP revealed downregulation of two genes related to platelet activation and iron ion and oxygen binding. In MSC, numerous changes in gene expression were observed. Three annotated genes were DE between NC and TN/UP. No genes were DE between adsorbent treatments (TN vs UP). However, comparing cows not fed AFB1 to those fed AFB1 alone (NC vs PC) revealed 120 DE genes, and 70 genes were DE between cows fed AFB1 without or with adsorbents (PC vs TN/UP). Of those DE genes, 49 were common to the comparisons PC vs NC and PC vs TN/UP. These genes represented functional clusters including glycoproteins and milk proteins, secretion, signaling, protein binding, transporter activity, and response to steroid hormones. Protein domains found to be differentially expressed included a- and b-caseins. Furthermore, approximately 20% of the common DE genes in MSC were mammary gland-specific. In summary, daily feeding of 2.8 mg of aflatoxin B1 to lactating dairy cows resulted in few DE genes in blood leukocytes, but elicited numerous changes in gene expression in milk somatic cells, many of which were modulated in cows fed TN or UP. [ABSTRACT FROM AUTHOR]

The limits of physical and chemical methods to decrease aflatoxins in feed ingredients, stimulated the search on biological approaches of degradation. Recently, we identified three Bacillus spp. candidates that showed in vitro activity to biodegradate aflatoxin Bl (AFB1). The aim of this study was to evaluate the biodegradation potential of previously selected Bacillus spp. provided as a direct-fed microbial candidate (DFM), in broiler chickens consuming feed containing different concentrations of AFB1. In the present study, three independent experiments were conducted. In Exp 1, broilers were allocated randomly to four groups: Control feed; feed + DFM; feed + 2 ppm AFB1; feed + DFM + 2 ppm AFB1. Each group had six replicates of 20 chickens (n = 120/group). In Exp 2, broilers were allocated randomly to six groups: Control feed; feed + DFM; feed + 1 ppm AFB1; feed + DFM + 1 ppm AFB1; feed + 1.5 ppm AFB1; feed + DFM + l.5 ppm AFB1. Each group had 5 replicates of 16 chickens (n = 801 group). In Exp 3, broilers were allocated randomly to six groups: Control feed; feed + DFM; feed + 50 ppb AFB1; feed + DFM + 50 ppb AFB1; feed + 500 ppb AFB1; feed + DFM + 500 ppb AFB1, each group had 5 replicates of 10 chickens (n = 801 group). In all experiments, chickens were fed starter (dl-d7) or grower diet (d8-d21) ad libitum until the end of the experiment at day 21. All broilers were individually weighed and body weight (BW), body weight gain (BWG), feed intake (FI) and feed conversion ratio (FCR) were obtained weekly. The results of the present study show clear evidence, that not all DFM are the same, and in this case, administration of 106 spores/gram of feed showed no beneficial performance effects in two out of three independent experiments. In addition, even though the individual isolates incorporated in the DFM showed some in vitro activity to biodegradate AFB1, when administered in the diets at 5 different concentrations of AFB1, no significant performance differences were observed when compared with their respective control diets. [ABSTRACT FROM AUTHOR]

This study aimed to determine the aflatoxin B1 (AFB1) binding capacity of a beer fermentation residue (BFR) containing Saccharomyces cerevisiae cells, and the efficacy of BFR to ameliorate the toxic effects of AFB1 on performance, serum biochemistry, and histology of broilers. The BFR was collected from a microbrewery, and the yeast cells were counted, dried, and milled before it was used in the study. In vitro evaluation of the BFR was conducted using different concentrations of AFB1 (2.0, 4.0, 8.0, 16.0, and 32.0 µg AFB1/mL) and 100 mg/10 mL of BFR at pH 3.0 or 6.0. Two hundred 1-day-old male broilers (Ross 308) were assigned to chick batteries and allowed ad libitum access to feed and water. A completely randomized design was used with 5 replicate pens of 5 chicks assigned to each of 4 dietary treatments from hatch to 21 d, which included: 1) basal diet (BD), with no BFR or AFB1; 2) BD supplemented with 1% BFR; 3) BD supplemented with 2 mg AFB1/kg of feed; and 4) BD supplemented with 2 mg AFB1/kg feed and 1% BFR. Performance variables were determined weekly, while serum analyses were performed on d 14 and 21. At the end of the study, chicks were anesthetized with carbon dioxide, euthanized by cervical dislocation, and the kidney, liver, and bursa of Fabricius were removed for determination of relative weights, and for histological evaluation. In vitro assays showed that the higher the initial AFB1 concentration in solution, the greater the AFB1 amount adsorbed by BFR at both pHs tested. Feed intake, BW gain, and concentrations of albumin, total protein, and globulin increased (P < 0.05) in broilers fed BFR+AFB1 (Diet 4), when compared to the birds receiving only AFB1 (Diet 2). Although BFR was not able to reduce or prevent the effects of AFB1 on relative weights of kidneys and liver, it reduced the severity of histological changes in the liver and kidney caused by AFB1. [ABSTRACT FROM AUTHOR]

Aflatoxin M 1 (AFM 1 ) is a pathogenic metabolite transferred from feed into milk from aflatoxin (AF) B 1 , B 2 , G 1 , and G 2 ; thus, it poses a human health risk. Therefore, effective mitigation strategies are needed to reduce animal and human exposure to AF. Study objectives were to evaluate a dietary adsorbent (Silicoglycidol, ATX) as a sequestering agent in AF-contaminated feed and to broadly examine how AF affects liver function and the immune system. Primiparous Holstein cows (n = 12; 279 ± 88 DIM and 675 ± 19 kg BW) were used in a replicated 3 × 3 Latin square design with 21-d periods in which d 1 to 14 were considered adaptation, and data collected on d 15 to 21 were used for analysis. Treatments were (1) control (CON) consisting of a basal diet, (2) AF diet consisting of CON+AF challenge (100 µg of AFB 1 /kg DMI), and (3) AF+ATX supplemented at 0.10% of dietary DMI. Feed intake and milk yield were recorded daily, fecal samples were collected on d 20 of each period, blood and urine samples were collected on d 21 of each period, and milk samples were collected on the last 2 d of each period. Data were analyzed using the MIXED procedure of SAS (SAS Institute Inc.). Milk yield and DMI were unaffected by treatment (26.8 ± 1.3 kg/d and 24.0 ± 0.9 kg/d, respectively). Similarly, neither milk composition nor DMI digestibility were affected by treatment. No AFM 1 was detected in CON cow milk or urine. Supplementing ATX reduced AFM 1 in milk (1.57 vs. 1.14 ± 0.1 µg/L for AF and AF+ATX, respectively) and urine (9.9 vs. 5.6 ± 1.1 µg/L for AF and AF+ATX, respectively). Consuming AF did not affect biomarkers of liver health or immune activation including alanine aminotransferase, aspartate aminotransferase, gamma glutamyltransferase, haptoglobin, and IgG. In summary, feeding ATX reduced the absorption and transfer of dietary AF to milk and urine., (© 2024.)

The objective was to evaluate the efficacy of 2 dietary mycotoxin sequestrants, Toxy-Nil (TN) or Unike Plus (UP), in reducing aflatoxin (AF) M 1 concentrations in milk of dairy cows challenged with dietary AF. Thirty-two mid-lactation Holstein cows were blocked by parity, days in milk, and milk yield and were randomly assigned within block to receive one of the following treatments: (1) 2.8 mg of AF/cow per d (positive control, PC), (2) 2.8 mg of AF + 100 g of TN/cow per d, (3) 2.8 mg of AF + 100 g of UP/cow per d, or (4) no AF and no additives (negative control, NC). For 7 d, treatments, dispersed in 150 g of sweet feed carrier, were top-dressed twice daily by mixing into the top portion of the TMR at each feeding. After the experimental period, cows were fed the NC diet and clearance of AFM 1 via milk was monitored for 7 d. Feed and water were available ad libitum throughout the trial. Treatments had no effect on feed intake, milk yield, milk composition, or milk somatic cell count. Relative intake of AF was similar among PC, TN, and UP, averaging 106.5, 107.6, and 102.5 ± 2.9 μg/kg of diet dry matter, respectively. Relative intake of mycotoxin sequestrants was similar between TN and UP, averaging 0.4 and 0.4 ± 0.1% of diet dry matter, respectively. Concentration and mass of AFM 1 secreted in milk and in urine were similar between TN and UP, but were lower than PC; concentrations in milk averaged 0.2, 0.3, and 0.6 ± 0.1 μg/kg, respectively, and mass secreted in milk averaged 8.1, 9.8, and 20.5 ± 1.7 μg/d. Concentrations in urine averaged 6.9, 7.4, and 14.2 ± 1.5 μg/L, respectively, and mass secreted in urine averaged 225.7, 250.8, and 521.6 ± 53.1 μg/d. Likewise, concentration and mass of free AF excreted in feces were similar between TN and UP, but were lower than PC; concentrations averaged 7.7, 8.9, and 12.4 ± 0.6 μg/kg, respectively, and mass excreted averaged 57.8, 69.6, and 95.6 ± 4.8 μg/d. Transfer of AF from feed to AFM 1 in milk was reduced by 63 and 52%, and in urine, by 57 and 52% for TN and UP, respectively. Transfer of AF from feed to free AF in feces was reduced by 38 and 26% for TN and UP, respectively. The clearance rate of AFM 1 in milk did not differ among PC, TN, and UP (46.1, 66.5, and 50.0 ± 6.7%/d, respectively). Results indicate that dietary inclusion of 100 g of TN or UP significantly reduced AFM 1 in milk of cows consuming TMR containing approximately 105 μg of AF/kg of diet dry matter. Results also suggest that both TN and UP reduced absorption of AF., (The Authors. Published by FASS Inc. and Elsevier Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).)