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Li N, Han J, Zhou Y, Zhang H, Xu X, He B, Liu M, Wang J, Wang Q. A rumen-derived bifunctional glucanase/mannanase uncanonically releases oligosaccharides with a high degree of polymerization preferentially from branched substrates. Carbohydr Polym 2024; 330:121828. [PMID: 38368107 DOI: 10.1016/j.carbpol.2024.121828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 01/07/2024] [Accepted: 01/12/2024] [Indexed: 02/19/2024]
Abstract
Glycoside hydrolases (GHs) are known to depolymerize polysaccharides into oligo-/mono-saccharides, they are extensively used as additives for both animals feed and our food. Here we reported the characterization of IDSGH5-14(CD), a weakly-acidic mesophilic bifunctional mannanase/glucanase of GH5, originally isolated from sheep rumen microbes. Biochemical characterization studies revealed that IDSGH5-14(CD) exhibited preferential hydrolysis of mannan-like and glucan-like substrates. Interestingly, the enzyme exhibited significantly robust catalytic activity towards branched-substrates compared to linear polysaccharides (P < 0.05). Substrate hydrolysis pattern indicated that IDSGH5-14(CD) predominantly liberated oligosaccharides with a degree of polymerization (DP) of 3-7 as the end products, dramatically distinct from canonical endo-acting enzymes. Comparative modeling revealed that IDSGH5-14(CD) was mainly comprised of a (β/α)8-barrel-like structure with a spacious catalytic cleft on surface, facilitating the enzyme to target high-DP or branched oligosaccharides. Molecular dynamics (MD) simulations further suggested that the branched-ligand, 64-α-D-galactosyl-mannohexose, was steadily accommodated within the catalytic pocket via a two-sided clamp formed by the aromatic residues. This study first reports a bifunctional GH5 enzyme that predominantly generates high-DP oligosaccharides, preferentially from branched-substrates. This provides novel insights into the catalytic mechanism and molecular underpinnings of polysaccharide depolymerization, with potential implications for feed additive development and high-DP oligosaccharides preparation.
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Affiliation(s)
- Nuo Li
- Institute of Dairy Science, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China; Key Laboratory of Molecular Animal Nutrition, Ministry of Education, Zhejiang University, Hangzhou 310058, China
| | - Junyan Han
- Institute of Dairy Science, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China; Key Laboratory of Molecular Animal Nutrition, Ministry of Education, Zhejiang University, Hangzhou 310058, China; College of Biological and Environmental Sciences, Zhejiang Wanli University, Ningbo 315100, China
| | - Yebo Zhou
- College of Biological and Environmental Sciences, Zhejiang Wanli University, Ningbo 315100, China
| | - Huien Zhang
- College of Biological and Environmental Sciences, Zhejiang Wanli University, Ningbo 315100, China
| | - Xiaofeng Xu
- Institute of Dairy Science, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China; Key Laboratory of Molecular Animal Nutrition, Ministry of Education, Zhejiang University, Hangzhou 310058, China; College of Biological and Environmental Sciences, Zhejiang Wanli University, Ningbo 315100, China
| | - Bo He
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Mingqi Liu
- Key Laboratory of Specialty Agri-product Quality and Hazard Controlling Technology of Zhejiang Province, College of Life Sciences, China Jiliang University, Hangzhou 310018, China
| | - Jiakun Wang
- Institute of Dairy Science, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China; Key Laboratory of Molecular Animal Nutrition, Ministry of Education, Zhejiang University, Hangzhou 310058, China
| | - Qian Wang
- Institute of Dairy Science, College of Animal Sciences, Zhejiang University, Hangzhou 310058, China; Key Laboratory of Molecular Animal Nutrition, Ministry of Education, Zhejiang University, Hangzhou 310058, China.
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Schrenk D, Bignami M, Bodin L, Chipman JK, del Mazo J, Grasl‐Kraupp B, Hogstrand C, Leblanc J, Nebbia CS, Nielsen E, Ntzani E, Petersen A, Sand S, Schwerdtle T, Vleminckx C, Wallace H, Gropp J, Mulder P, Oswald IP, Woutersen R, Gómez Ruiz JÁ, Rovesti E, Hoogenboom L(R. Risks for animal health related to the presence of ergot alkaloids in feed. EFSA J 2024; 22:e8496. [PMID: 38264299 PMCID: PMC10804272 DOI: 10.2903/j.efsa.2024.8496] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2024] Open
Abstract
The European Commission requested EFSA to provide an update of the 2012 Scientific Opinion of the Panel on Contaminants in the Food Chain (CONTAM) on the risks for animal health related to the presence of ergot alkaloids (EAs) in feed. EAs are produced by several fungi of the Claviceps and Epichloë genera. This Opinion focussed on the 14 EAs produced by C. purpurea (ergocristine, ergotamine, ergocornine, α- and β-ergocryptine, ergometrine, ergosine and their corresponding 'inine' epimers). Effects observed with EAs from C. africana (mainly dihydroergosine) and Epichloë (ergovaline/-inine) were also evaluated. There is limited information on toxicokinetics in food and non-food producing animals. However, transfer from feed to food of animal origin is negligible. The major effects of EAs are related to vasoconstriction and are exaggerated during extreme temperatures. In addition, EAs cause a decrease in prolactin, resulting in a reduced milk production. Based on the sum of the EAs, the Panel considered the following as Reference Points (RPs) in complete feed for adverse animal health effects: for pigs and piglets 0.6 mg/kg, for chickens for fattening and hens 2.1 and 3.7 mg/kg, respectively, for ducks 0.2 mg/kg, bovines 0.1 mg/kg and sheep 0.3 mg/kg. A total of 19,023 analytical results on EAs (only from C. purpurea) in feed materials and compound feeds were available for the exposure assessment (1580 samples). Dietary exposure was assessed using two feeding scenarios (model diets and compound feeds). Risk characterisation was done for the animals for which an RP could be identified. The CONTAM Panel considers that, based on exposure from model diets, the presence of EAs in feed raises a health concern in piglets, pigs for fattening, sows and bovines, while for chickens for fattening, laying hens, ducks, ovines and caprines, the health concern related to EAs in feed is low.
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Stanford K, Schwartzkopf-Genswein KS, Meléndez DM, Ngo S, Harding M, McAllister TA, Schatzmayr D, Swift ML, Blakley B, Ribeiro GO. Effects of Heating, Pelleting, and Feed Matrix on Apparent Concentrations of Cereal Ergot Alkaloids in Relation to Growth Performance and Welfare Parameters of Backgrounding Beef Steers. Toxins (Basel) 2022; 14:toxins14090580. [PMID: 36136518 PMCID: PMC9500729 DOI: 10.3390/toxins14090580] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 08/15/2022] [Accepted: 08/22/2022] [Indexed: 12/04/2022] Open
Abstract
As the contamination of cereal grains with ergot has been increasing in Western Canada, studies were undertaken to evaluate the impacts of heating (60, 80, 120, or 190 °C) alone or in combination with pelleting on concentrations of ergot alkaloids. Fifteen samples of ergot-contaminated grain from Alberta and Saskatchewan were assayed for R and S epimers of six alkaloids (ergocryptine, ergocristine, ergocornine, ergometrine, ergosine, and ergotamine) using HPLC MS/MS. Five samples with distinct alkaloid profiles were then selected for heating and pelleting studies. Heating resulted in a linear increase (p < 0.05) of total R and total S epimers with increasing temperature, although some individual R epimers were stable (ergometrine, ergosine, ergotamine). Pelleting also increased (p < 0.05) concentrations of total R and total S epimers detected, although ergometrine concentration decreased (p < 0.05) after pelleting. A feeding study arranged in a 2 × 2 factorial structure used 48 backgrounding Angus-cross steers fed four different diets: (1) Control Mash (CM, no added ergot), (2) Control Pellet (CP), (3) Ergot Mash (EM), or (4) Ergot Pellet (EP). Pelleting heated the ergot to 90−100 °C under 4 bars pressure, but the ergot used in the feeding study was not otherwise heated. Alkaloid concentrations of EM and EP varied by up to 1.1 mg/kg depending on the feed matrix assayed. No differences among treatments were noted for growth performance, feed intake, feed conversion, concentrations of serum prolactin and haptoglobin, hair cortisol, or in temperatures of extremities measured by infrared thermography. The only negative impacts of ergot alkaloids were on blood parameters indicative of reduced immune function or chronic inflammation. Pelleting did not heighten the negative clinical outcomes of ergot, although alkaloid concentrations of pelleted feed increased depending on the matrix assayed. It was hypothesized that the heat and pressure associated with pelleting may enhance the recovery of alkaloids from pelleted feed.
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Affiliation(s)
- Kim Stanford
- Department of Biological Sciences, University of Lethbridge, 4401 University Dr. Lethbridge, Lethbridge, AB T1K 3M4, Canada
- Correspondence:
| | - Karen S. Schwartzkopf-Genswein
- Agriculture and Agri-Food Canada Research and Development Center, 5401-1st Ave. S. Lethbridge, Lethbridge, AB T1J 4B1, Canada
| | - Daniela M. Meléndez
- Agriculture and Agri-Food Canada Research and Development Center, 5401-1st Ave. S. Lethbridge, Lethbridge, AB T1J 4B1, Canada
| | - Skyler Ngo
- Department of Biological Sciences, University of Lethbridge, 4401 University Dr. Lethbridge, Lethbridge, AB T1K 3M4, Canada
| | - Michael Harding
- Alberta Agriculture, Forestry and Rural Economic Development, Crop Diversification Center South, Brooks, AB T1R 1E6, Canada
| | - Tim A. McAllister
- Agriculture and Agri-Food Canada Research and Development Center, 5401-1st Ave. S. Lethbridge, Lethbridge, AB T1J 4B1, Canada
| | - Dian Schatzmayr
- DSM–BIOMIN Research Center, Technopark 1, 3430 Tulln, Austria
| | - Mary Lou Swift
- Department of Agricultural, Food and Nutritional Sciences, University of Alberta, Edmonton, AB T6G 2P5, Canada
| | - Barry Blakley
- Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK S7N 5A2, Canada
| | - Gabriel O. Ribeiro
- Department of Animal and Poultry Science, University of Saskatchewan, Saskatoon, SK S7N 5A8, Canada
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van den Brand AD, Bokkers BGH, te Biesebeek JD, Mengelers MJB. Combined Exposure to Multiple Mycotoxins: An Example of Using a Tiered Approach in a Mixture Risk Assessment. Toxins (Basel) 2022; 14:toxins14050303. [PMID: 35622550 PMCID: PMC9145316 DOI: 10.3390/toxins14050303] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Revised: 04/12/2022] [Accepted: 04/21/2022] [Indexed: 01/27/2023] Open
Abstract
Humans are exposed to mycotoxins on a regular basis. Exposure to a mixture of mycotoxins may, therefore, result in a combination of adverse effects, or trigger the same effects. This should be accounted for when assessing the combined risk of multiple mycotoxins. Here, we show the outcome of using different approaches in assessing the risks related to the combined exposure to mycotoxins. We performed a tiered approach using assessment groups with a common target organ (kidney, liver and haematologic system), or a common adverse effect (phenomenon) (reduced white blood cell count), to combine the exposure to mycotoxins. The combined exposure was calculated for the individuals in this assessment, using the Monte Carlo Risk Assessment (MCRA) tool. The risk related to this combined exposure was assessed using toxicological reference values, e.g., health based guidance values. We show that estimating the combined risk by adding the single compounds’ risk distributions slightly overestimates the combined risk in the 95th percentile, as compared to combining the exposures at an individual level. We also show that relative potency factors can be used to refine the mixture risk assessment, as compared to ratios of toxicological reference values with different effect sizes and assessment factors.
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Gerber PF, Gould N, McGahan E. Potential contaminants and hazards in alternative chicken bedding materials and proposed guidance levels: a review. Poult Sci 2020; 99:6664-6684. [PMID: 33248583 PMCID: PMC7705057 DOI: 10.1016/j.psj.2020.09.047] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 09/07/2020] [Accepted: 09/15/2020] [Indexed: 12/18/2022] Open
Abstract
Bedding material or litter is an important requirement of meat chicken production which can influence bird welfare, health, and food safety. A substantial increase in demand and cost of chicken bedding has stimulated interest in alternative bedding sources worldwide. However, risks arising from the use of alternative bedding materials for raising meat chickens are currently unknown. Organic chemicals, elemental, and biological contaminants, as well as physical and management hazards need to be managed in litter to protect the health of chickens and consequently that of human consumers. This requires access to information on the transfer of contaminants from litter to food to inform risk profiles and assessments to guide litter risk management. In this review, contaminants and hazards of known and potential concern in alternative bedding are described and compared with existing standards for feed. The contaminants considered in this review include organic chemical contaminants (e.g., pesticides), elemental contaminants (e.g., arsenic, cadmium, and lead), biological contaminants (phytotoxins, mycotoxins, and microorganisms), physical hazards, and management hazards. Reference is made to scientific literature for acceptable levels of the above contaminants in chicken feed that can be used for guidance by those involved in selecting and using bedding materials.
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Affiliation(s)
- Priscilla F Gerber
- Animal Science, School of Environmental and Rural Science, University of New England, Armidale, NSW 2351, Australia.
| | - Nic Gould
- Integrity Ag and Environment, New England Highway, Highfields, QLD 4352, Australia
| | - Eugene McGahan
- Integrity Ag and Environment, New England Highway, Highfields, QLD 4352, Australia
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Schwake-Anduschus C, Lorenz N, Lahrssen-Wiederholt M, Lauche A, Dänicke S. German monitoring 2012–2014: ergot of Claviceps purpurea and ergot alkaloids (EA) in feedingstuffs and their toxicological relevance for animal feeding. J Verbrauch Lebensm 2020. [DOI: 10.1007/s00003-020-01298-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
AbstractFeedingstuffs are frequently contaminated with sclerotia (ergot) of the phytopathogenic fungus Claviceps purpurea. Ergot contains ergot alkaloids (EA), but the amount and composition of these substances may be highly variable hampering the extrapolation of the amount of EA from the ergot content. 600 different feed samples from the harvest years 2011–2014 (rye, triticale, wheat, mixed cereal grains or compound feed), preferably those with visible ergot infestation, were analyzed for both parameters ergot and EA content in a German monitoring program. The analytical results were employed for statistical evaluation using the software JMP® 13. The data show that the correlation between the ergot and the EA content was rather poor, especially for rye, the grain most frequently contaminated with ergot and EA. Consequently, effects on animal health correlated much better with EA than with ergot content. Furthermore, it shows that the current European law for undesirable substances (Directive 2002/32/EC) restricting the ergot content in feed materials and compound feed containing unground cereals is not fully sufficient to protect animal health. Therefore, preliminary guidance values for species-specific critical values for total EA content in the diets are derived and suggested for practical use. Further research is needed to verify these preliminary guidance values and to improve risk evaluation in consideration of the significant variability in the species-specific sensitivity.
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7
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Britt JL, Greene MA, Bridges WC, Klotz JL, Aiken GE, Andrae JG, Pratt SL, Long NM, Schrick FN, Strickland JR, Wilbanks SA, Miller MF, Koch BM, Duckett SK. Ergot alkaloid exposure during gestation alters. I. Maternal characteristics and placental development of pregnant ewes1. J Anim Sci 2019; 97:1874-1890. [PMID: 30895321 DOI: 10.1093/jas/skz068] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2018] [Accepted: 02/15/2019] [Indexed: 12/11/2022] Open
Abstract
Tall fescue [Lolium arundinaceum (Scheyreb.) Darbysh] is the primary cool season forage grass in the Southeastern United States. Most tall fescue contains an endophytic fungus (Epichloë coenophiala) that produces ergot alkaloids and upon ingestion induces fescue toxicosis. The objective of this study was to assess how exposure to endophyte-infected (E+; 1.77 mg hd-1 d-1 ergovaline and ergovalinine) or endophyte-free (E-; 0 mg hd-1 d-1 ergovaline and ergovalinine) tall fescue seed fed during 2 stages of gestation (MID, days 35-85/LATE, days 86-133) alters placental development. Thirty-six, fescue naïve Suffolk ewes were randomly assigned to 1 of 4 fescue treatments: E-/E-, E-/E+, E+/E-, or E+/E+. Ewes were individually fed the same amount of E+ or E- seed mixed into total mixed ration during MID and LATE gestation. Terminal surgeries were conducted on day 133 of gestation. Ewes fed E+ fescue seed had elevated (P < 0.001) ergot alkaloid excretion and reduced (P < 0.001) prolactin levels during the periods when fed E+ seed. Ewes switched on day 86 from E- to E+ seed had a 4% reduction (P = 0.005) in DMI during LATE gestation, which translated to a 2% reduction (P = 0.07) in DMI overall. Average daily gain was also reduced (P = 0.049) by 64% for E-/E+ ewes during LATE gestation and tended to be reduced (P = 0.06) by 33% overall. Ewes fed E+ seed during LATE gestation exhibited a 14% and 23% reduction in uterine (P = 0.03) and placentome (P = 0.004) weights, respectively. Caruncle weights were also reduced by 28% (P = 0.003) for E-/E+ ewes compared with E-/E- and E+/E-. Ewes fed E+ seed during both MID and LATE gestation exhibited a 32% reduction in cotyledon (P = 0.01) weights, whereas ewes fed E+ seed only during MID gestation (E+/E-) had improved (P = 0.01) cotyledon weights. The percentage of type A placentomes tended to be greater (P = 0.08) for E+/E+ ewes compared with other treatments. Other placentome types (B, C, or D) did not differ (P > 0.05). Total fetal weight per ewe was reduced (P = 0.01) for ewes fed E+ seed during LATE gestation compared with E-; however, feeding E+ seed during MID gestation did not alter (P = 0.70) total fetal weight per ewe. These results suggest that exposure to ergot alkaloids during LATE (days 86-133) gestation has the greatest impact on placental development by reducing uterine and placentome weights. This, in turn, reduced total fetal weight per ewe by 15% in ewes fed E+ seed during LATE gestation (E-/E+ and E+/E+).
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Affiliation(s)
- Jessica L Britt
- Department of Animal and Veterinary Sciences, Clemson University, Clemson, SC
| | - Maslyn A Greene
- Department of Animal and Veterinary Sciences, Clemson University, Clemson, SC
| | - William C Bridges
- Department of Mathematical Sciences, Clemson University, Clemson, SC
| | - James L Klotz
- USDA-ARS, Forage Production Research Unit, Lexington, KY
| | - Glen E Aiken
- USDA-ARS, Forage Production Research Unit, Lexington, KY
| | - John G Andrae
- Simpson Research and Education Center, Clemson University, Clemson, SC
| | - Scott L Pratt
- Department of Animal and Veterinary Sciences, Clemson University, Clemson, SC
| | - Nathan M Long
- Department of Animal and Veterinary Sciences, Clemson University, Clemson, SC
| | | | - James R Strickland
- Department of Animal and Veterinary Sciences, Clemson University, Clemson, SC
| | - Sarah A Wilbanks
- Department of Animal and Veterinary Sciences, Clemson University, Clemson, SC
| | - Markus F Miller
- Department of Animal and Veterinary Sciences, Clemson University, Clemson, SC
| | - Brandon M Koch
- Department of Animal and Veterinary Sciences, Clemson University, Clemson, SC
| | - Susan K Duckett
- Department of Animal and Veterinary Sciences, Clemson University, Clemson, SC
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Stanford K, Swift ML, Wang Y, McAllister TA, McKinnon J, Blakley B, Chaves AV. Effects of Feeding a Mycotoxin Binder on Nutrient Digestibility, Alkaloid Recovery in Feces, and Performance of Lambs Fed Diets Contaminated with Cereal Ergot. Toxins (Basel) 2018; 10:toxins10080312. [PMID: 30071666 PMCID: PMC6115947 DOI: 10.3390/toxins10080312] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 07/05/2018] [Accepted: 07/30/2018] [Indexed: 11/16/2022] Open
Abstract
As contamination with cereal ergot has been increasing in western Canada, this study evaluated impacts of feeding a mycotoxin binder (Biomin® II; BB) on nutrient digestibility, alkaloid recovery in feces, and lamb growth performance. Forty-eight ram lambs (25.9 ± 1.4 kg) were randomly assigned to one of four barley-based diets: Control (C), no added alkaloids, Control + BB fed at 30 g/head per day (CBB); Ergot, 2564 ppb total R + S epimers (E); Ergot + BB, 2534 ppb R + S epimers (EBB). Lambs were fed ab libitum for up to 11 weeks until slaughter at >46 kg live weight. Both average daily gain (ADG) and gain/feed ratio were greater (p < 0.01) for lambs fed C and CBB diets as compared with those containing added ergot, although dry matter intake was not affected by dietary ergot or BB. Serum prolactin concentrations were two times higher in EBB- compared with E-fed lambs (p < 0.05), although both were lower than in C or CBB (p < 0.001) lambs. Rectal temperatures were greater in lambs receiving dietary ergot (p ≤ 0.001) than in C- and CBB-fed lambs. In a digestibility study using eight ram lambs, treatment with BB increased neutral detergent fiber (NDF) digestibility (p = 0.01). Nitrogen retention (g) was greater (p < 0.05) for lambs receiving C or CBB compared with ergot-contaminated diets. Feces of EBB lambs had 38.5% greater (p < 0.001) recovery of alkaloids compared with those fed E. Based on sparing of prolactin, BB may reduce impacts of ergot alkaloids by increasing their excretion in feces. Accordingly, concentrations of dietary alkaloids, which would not harm sheep, would be increased by feeding BB.
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Affiliation(s)
- Kim Stanford
- Livestock Research Section, Alberta Agriculture and Forestry, Lethbridge, AB T1J 4V6, Canada.
| | - Mary Lou Swift
- Department of Agriculture, Food and Nutritional Sciences, University of Alberta, Edmonton, AB T6G 2P5, Canada.
| | - Yuxi Wang
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, AB T1J 4B1, Canada.
| | - Tim A McAllister
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Centre, Lethbridge, AB T1J 4B1, Canada.
| | - John McKinnon
- Department of Animal and Poultry Science, University of Saskatchewan, Saskatoon, SK S7N 5B4, Canada.
| | - Barry Blakley
- Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK S7N 5A8, Canada.
| | - Alex V Chaves
- School of Life and Environmental Sciences, University of Sydney, Sydney 2006, NSW, Australia.
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Dellafiora L, Dall'Asta C, Galaverna G. Toxicodynamics of Mycotoxins in the Framework of Food Risk Assessment-An In Silico Perspective. Toxins (Basel) 2018; 10:E52. [PMID: 29360783 PMCID: PMC5848153 DOI: 10.3390/toxins10020052] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2017] [Revised: 01/16/2018] [Accepted: 01/20/2018] [Indexed: 12/11/2022] Open
Abstract
Mycotoxins severely threaten the health of humans and animals. For this reason, many countries have enforced regulations and recommendations to reduce the dietary exposure. However, even though regulatory actions must be based on solid scientific knowledge, many aspects of their toxicological activity are still poorly understood. In particular, deepening knowledge on the primal molecular events triggering the toxic stimulus may be relevant to better understand the mechanisms of action of mycotoxins. The present work presents the use of in silico approaches in studying the mycotoxins toxicodynamics, and discusses how they may contribute in widening the background of knowledge. A particular emphasis has been posed on the methods accounting the molecular initiating events of toxic action. In more details, the key concepts and challenges of mycotoxins toxicology have been introduced. Then, topical case studies have been presented and some possible practical implementations of studying mycotoxins toxicodynamics have been discussed.
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Affiliation(s)
- Luca Dellafiora
- Department of Food and Drug, University of Parma, 43124 Parma, Italy.
| | - Chiara Dall'Asta
- Department of Food and Drug, University of Parma, 43124 Parma, Italy.
| | - Gianni Galaverna
- Department of Food and Drug, University of Parma, 43124 Parma, Italy.
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Coufal-Majewski S, Stanford K, McAllister T, Wang Y, Blakley B, McKinnon J, Swift ML, Chaves AV. Effects of Continuously Feeding Diets Containing Cereal Ergot Alkaloids on Nutrient Digestibility, Alkaloid Recovery in Feces, and Performance Traits of Ram Lambs. Toxins (Basel) 2017; 9:E405. [PMID: 29257065 PMCID: PMC5744125 DOI: 10.3390/toxins9120405] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2017] [Revised: 12/05/2017] [Accepted: 12/14/2017] [Indexed: 02/03/2023] Open
Abstract
Allowable limits for cereal ergot alkaloids in livestock feeds are being re-examined, and the objective of this study was to compare nutrient digestibility, growth performance and carcass characteristics of ram lambs fed a range of alkaloid concentrations, including the maximum currently allowed in Canada (2 to 3 ppm). Four pelleted diets were fed: control, with no added alkaloids; 930; 1402; and 2447 ppb alkaloids based on total R and S epimers. Eight ram lambs (30.0 ± 3.1 kg) were used to examine the impacts of dietary treatments on nutrient digestibility and alkaloid recovery from feces. Concentrations of dietary alkaloids evaluated did not affect nutrient digestibility or N metabolism. Excepting ergocornine and ergocryptine, recovery of alkaloids in feces varied among periods, suggesting that individual lambs may differ in their ability to metabolize ergocristine, ergometrine, ergosine, ergotamine and their S epimers. In a second experiment, ram lambs (n = 47, 30 ± 8 kg) were randomly assigned to a diet and weighed weekly until they achieved a slaughter weight of ≥ 45 kg (average 9 weeks; range 6 to 13 weeks). Intake of DM did not differ (p = 0.91) among diets, although lambs fed 2447 ppb alkaloids had a lower (p < 0.01) ADG than did lambs receiving other treatments. The concentration of serum prolactin linearly declined (p < 0.01) with increasing alkaloids. Feeding 2447 ppb total alkaloids negatively impacted growth, while feeding 1402 ppb did not harm growth performance, but reduced carcass dressing percentage. Due to different concentrations of alkaloids affecting growth and carcass characteristics in the present study, determining allowable limits for total dietary alkaloids will require a better understanding of impacts of alkaloid profiles and interactions among individual alkaloids.
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Affiliation(s)
- Stephanie Coufal-Majewski
- Faculty of Science, School of Life and Environmental Sciences, University of Sydney, Sydney, NSW 2006, Australia.
| | - Kim Stanford
- Livestock Research Section, Alberta Agriculture and Forestry, Lethbridge, AB T1J 4V6, Canada.
| | - Tim McAllister
- Science and Technology Branch, Agriculture and Agri-Food Canada, Lethbridge, AB T1J 4B1, Canada.
| | - Yuxi Wang
- Science and Technology Branch, Agriculture and Agri-Food Canada, Lethbridge, AB T1J 4B1, Canada.
| | - Barry Blakley
- Department of Veterinary Biomedical Sciences, University of Saskatchewan, Saskatoon, SK S7N 5B4, Canada.
| | - John McKinnon
- Department of Animal Science, University of Saskatchewan, Saskatoon, SK S7N 5B4, Canada.
| | - Mary Lou Swift
- Ruminant Nutrition, Hi-Pro Feeds, Okotoks, AB T1S 1A2, Canada.
| | - Alexandre V Chaves
- Faculty of Science, School of Life and Environmental Sciences, University of Sydney, Sydney, NSW 2006, Australia.
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