脱氧雪腐镰刀菌烯醇对肠道屏障的影响及其作用机制

脱氧雪腐镰刀菌烯醇(DON)对食物和饲料的污染是一个全球性的问题,它不仅影响了人类和动物的健康,还造成了严重的经济损失。肠道是机体抵御病原体和毒素入侵的第1道屏障,近年来的研究表明DON不仅抑制了肠道对营养物质的吸收,还影响了肠道屏障和细胞紧密连接,并改变了肠道微生物组成。本文将围绕DON对肠道屏障的影响及其作用机制进行综述。     

脱氧雪腐镰刀菌烯醇对仔猪肠道健康影响的研究进展

猪对脱氧雪腐镰刀菌烯醇(DON)的敏感性明显高于其他动物,其肠道是接触和吸收DON的主要场所。仔猪由于肠道发育尚未完善,容易受到DON污染引起肠道上皮细胞凋亡,促使肠道自由基和促炎性细胞因子分泌增加,破坏紧密连接蛋白,导致肠道形态结构和屏障功能损伤,打破肠道微生物区系平衡,从而影响仔猪肠道健康和正常生长。本文将围绕肠道形态结构、肠道屏障、肠道微生物、肠道黏膜免疫和肠道氧化应激等方面对近年来有关DON影响仔猪肠道健康的研究进行综述,以期为饲料中DON污染的防治措施以及仔猪肠道健康的营养调控提供科学依据。     

脱氧雪腐镰刀菌烯醇致动物厌食和呕吐机制的探讨

脱氧雪腐镰刀菌烯醇( DON)是一种由镰刀菌产生的霉菌毒素,其广泛存在于食品和饲料中,严重威胁着人类的健康和食品安全. DON又称呕吐毒素,它可对动物的肠道、大脑以及神经系统产生毒害作用,致使动物产生厌食和呕吐反应.本文综述了DON诱导厌食和呕吐反应的机制,并阐述了肠道微生物和DON诱导厌食和呕吐反应的潜在联系,以期为...     

脱氧雪腐镰刀菌烯醇导致厌食和呕吐的机制研究进展

由镰刀菌产生的脱氧雪腐镰刀菌烯醇(DON)广泛存在于谷物及其加工产品中,对动物和人类健康有着潜在的危害。DON具有多方面的毒性作用,而厌食和呕吐是机体摄入DON后出现的最典型症状,厌食和呕吐的产生主要归因于DON对中枢神经系统和胃肠道食欲因子的影响。DON可直接作用于中枢神经系统的呕吐中枢产生呕吐反射,同时激活下丘脑神经元分泌食欲调节因子影响采食;DON可诱导肠内分泌细胞分泌肽YY、胆囊收缩素等食欲调节因子从而引发厌食;DON对中枢神经系统和胃肠道分泌的影响又可通过肠-脑轴产生关联;此外,细胞因子及肠道微生物也部分参与了反应的介导。本文综述了DON诱发机体出现厌食和呕吐的可能机制,以期为找到相应解决措施提供理论指导。     

有机酸对猪肠道菌群的调节作用及其抑菌机制研究进展

肠道菌群平衡与动物机体健康及生长发育密切相关,有机酸(organic acid, OA)作为一种绿色安全的功能性饲料添加剂,对动物具有抑菌、促消化、调节菌群平衡等作用。随着饲料产业的不断发展,OA已从饲料酸化、防腐、防霉逐渐向制剂化、动物生长促进剂和替抗产品转变,已成为畜牧行业广泛使用的一种功能性添加剂。笔者综述了猪肠道菌群的形成和分布,OA调节猪肠道菌群的组成结构和多样性及其对肠道菌群代谢产物产生和肠道免疫反应等方面的影响,并对其调控猪肠道菌群的作用机制进行探讨,旨在进一步揭示OA与肠道菌群的相互影响机制,为促进猪肠道健康与OA的合理利用提供借鉴。     

新型饲料添加剂作为抗生素替代物 对断奶仔猪生长性能及肠道功能的影响

仔猪的断奶腹泻是仔猪生产中最为常见且亟待解决的问题.抗生素是20世纪最重要的发现之一,在21世纪被广泛应用于动物的疾病治疗,尤其是针对仔猪断奶后产生的腹泻等疾病.然而近年来,抗生素的大量使用甚至滥用造成了动物机体对抗生素的耐药性,这一现象在全世界范围引起了人们的高度关注.因此,用新型饲料添加剂替代抗生素在动物饲料中的使用成为了最新的研究热点.最新发现的抗生素替代物主要包括:酶制剂、 益生元、 益生素、 矿物质、 酸化剂、 植物以及植物提取物等.它们作为新型的饲料添加剂,从不同程度上能够对动物的机体免疫功能和肠道微生物产生一定的影响.本文主要针对新型饲料添加剂的使用和作用特点进行综述,并且阐述了以上添加剂对断奶仔猪生长性能及肠道功能的影响.     

厚朴酚对动物肠道健康的影响及其调控机制

动物肠道是机体重要的消化、吸收和免疫器官，同时也是机体抵御外界环境的重要防线。因而，保持肠道健康不仅可以增强动物对营养物质的消化吸收，而且对动物整体健康也十分重要，从而提高动物生产性能和生产水平。厚朴酚是一种从中药厚朴的茎皮中分离出的植物多酚类物质，在畜禽养殖生产中已被广泛应用。研究显示，厚朴酚可通过改善宿主肠道形态、调节肠道蠕动功能和增强肠道屏障功能，继而维护肠道乃至机体健康。本文主要综述厚朴酚调节动物肠道健康的作用机制，旨在为新型饲料添加剂的开发及其在畜禽生产中的应用提供参考。     

低蛋白质饲粮对家禽肠道健康的影响研究进展

通过在低蛋白质饲粮中补充合成氨基酸,是解决当前养殖生产中蛋白质饲料资源短缺和降低饲料成本的有效途径之一。健全的肠道功能在维持机体健康和生产性能方面发挥至关重要的作用。动物肠道需要一定水平的营养物质来维持肠黏膜的生长以及发挥肠道功能,饲粮蛋白质水平对于肠道结构、消化吸收及免疫功能等具有显著影响。本文综述了低蛋白质饲粮对家禽肠道健康、肠道形态及屏障结构影响的研究进展,旨在为低蛋白质饲粮及相关技术在肠道功能研究和家禽生产上进一步推广应用提供参考。     

低聚木糖在畜牧生产中的应用研究

低聚木糖是一种新型饲料添加剂,具有促进肠道有益菌增殖、吸附肠道病原菌、提高机体免疫力、促进脂类代谢和矿物质代谢以及抗氧化等作用。低聚木糖作为饲料添加剂在饲料工业中的应用也得到肯定,已广泛应用于猪、禽、反刍动物和水产动物等饲料。研究结果证实,低聚木糖能够改善动物生产性能、提高动物机体免疫力和抗病力,另外,添加低聚木糖还可以降低饲料中的药物用量,降低药物残留,有利于环保。主要介绍了低聚木糖的化学结构和理化特性、作用机理以及在畜牧业生产中的应用效果,并进行了前景展望。     

短链脂肪酸在水产养殖中的应用研究进展

短链脂肪酸（SCFAs）,也称为挥发性脂肪酸,是肠道菌群通过发酵膳食纤维产生的有益代谢物,可以为动物提供能量,促进肠胃机能,调节机体免疫功能,调整肠道菌群平衡。目前,其在水产上的研究及应用还较少,本文概述了SCFAs作为一种有效饲料添加剂在水产养殖领域的应用,以及对高糖高脂所导致的生长下降、肠道炎症、代谢功能紊乱等方面的作用。     

Aflatoxin B_1, zearalenone and deoxynivalenol in feed ingredients and complete feed from different Province in China

Background: The current study was carried out to provide a reference for monitory of aflatoxin B_1(AFB_1),zearalenone(ZEN) and deoxynivalenol(DON) contamination in feed ingredients and complete feeds were collected from different Province in China from 2013 to 2015.Methods: A total of 443 feed ingredients, including 220 corn, 24 wheat, 24 domestic distillers dried grains with soluble(DDGS), 55 bran, 20 wheat shorts and red dog, 37 imported DDGS, 34 corn germ meal and 29 soybean meal as well as 127 complete feeds including 25 pig complete feed(powder), 90 pig complete feed(pellet), six duck complete feed and six cattle complete feed were randomly collected from different Province in China,respectively, by high-performance chromatography in combined with UV or fluorescence analysis.Results: The incidence rates of AFB_1, ZEN and DON contamination of feed ingredients and complete feeds were80.8, 92.3 and 93.9 %, respectively. The percentage of positive samples for DON ranged from 66.7 to 100 %.Domestic DDGS and imported DDGS presented the most serious contamination AFB_1, ZEN and DON contamination levels of feeds ranged from 61.5 to 100 %, indicated that serious contamination over the studied 3-year period.Conclusion: The current data provide clear evidence that AFB_1, ZEN and DON contamination of feed ingredients and complete feeds in different Province in China is serious and differs over past 3-year. The use of corn, domestic DDGS, imported DDGS and corn germ meal, which may be contaminated with these three mycotoxins, as animal feed may triggered a health risk for animal. Feeds are most contaminated with DON followed by ZEN and AFB_1.Mycotoxins contamination in feed ingredients and complete feeds should be monitored routinely in China.     

饲料中呕吐毒素对不同阶段商品猪及种猪的影响

我国不仅是畜牧业生产和消费大国,同时饲料产量也居世界首位,作为饲料中最常添加的谷物原料,其质量安全对饲料生产和养殖业有着重要影响。小麦、玉米等谷物在其生长、收获及加工等阶段未及时按规定处理会产生大量的霉菌毒素,其中呕吐毒素最为常见。呕吐毒素(DON)主要由镰刀菌属(如禾谷镰刀菌、尖孢镰刀菌等)产生,会造成不同阶段商品猪及种猪呕吐、肌肉出血、生长性能和繁殖力的下降等。本文综述了饲料中DON的污染现状及其对养猪生产的危害,进而提出了综合防治措施,为畜牧业生产者更好地防治DON污染、提高养殖收益提供系统科学参考。     

Ingestion of low doses of deoxynivalenol does not affect hematological, biochemical, or immune responses of piglets

Deoxynivalenol (DON), a mycotoxin produced by Fusarium spp., is a frequent contaminant of cereals. Because of their rich cereal diet, pigs could be exposed to this mycotoxin. Pigs are among the animal species showing the greatest sensitivity to DON. Effects of intermediate to high levels of DON on pigs are well known and include feed refusal, decreased feed intake, and alteration of the immune response. Effects of low levels of DON, which are commonly detected in contaminated feed, remain unknown. The aim of this study was to investigate the effect of a diet naturally contaminated with a low concentration of DON (0, 280, 560, or 840 microg/kg of feed) on performance of weanling piglets and on 34 hematological, biochemical, and immune variables. Low doses of DON did not alter the animal performances (feed intake and BW gain). Such low levels of DON did not modify the 9 hematological variables measured (including white blood cell, red blood cell, and platelet counts, relative numbers of neutrophils and lymphocytes, and hematocrit and hemoglobin concentrations) or the 18 biochemical variables tested (including cations, glucose, urea, creatinine, bilirubin, cholesterol and triglyceride concentrations, and plasma enzyme activity). Similarly, no effect of low doses of DON was observed on the immune responses of the animals (immunoglobulin subset concentration, lymphocyte proliferation, and cytokine production).     

脱氧雪腐镰刀菌烯醇的毒性作用及其机理

脱氧雪腐镰刀菌烯醇(deoxynivalenol,DON)是谷物中最为常见的一种真菌毒素,其降低畜禽的生产性能,并且对动物免疫系统、细胞信号传导和基因的表达均有不同程度的影响。本文从DON的物理特性、代谢,尤其是其对动物采食量、免疫系统、肠道功能、细胞凋亡、基因表达和丝裂原活化蛋白激酶(MAPKs)信号通路等方面的影响及机理以及降解的一般方法作一综述,以期为DON的进一步研究和谷物中DON的降解提供参考。     

我国西南地区肉禽配合饲料中霉菌毒素的污染分布规律

本研究旨在了解我国西南地区肉禽配合饲料中霉菌毒素的污染分布规律。从西南地区(四川、重庆、贵州、广西和云南)不同规模饲料厂随机抽取100份肉禽(肉小鸭前期、肉仔鸡前期和肉仔鸡后期)配合饲料样品,用酶联免疫吸附试验(ELISA)试剂盒初筛和高效液相色谱法复查测定样品中黄曲霉毒素B_1(AFB_1)、玉米赤霉烯酮(ZON)、呕吐毒素(DON)和伏马毒素(FB)的含量。结果表明,肉禽配合饲料中AFB_1、DON、ZON和FB的检出率分别为89%、96%、85%和94.74%,AFB_1和ZON的超标率分别为18%和5%,而DON和FB无超标样品;不同地区的肉禽配合饲料中AFB_1、DON和ZON的平均含量之间存在差异,其中,肉禽配合饲料中AFB_1含量最高的是重庆(11.76μg/kg),DON含量最高的是四川(1.23 mg/kg),ZON含量最高的是云南(0.26 mg/kg);不同品种的肉禽配合饲料中AFB_1含量由高到底依次是肉小鸭前期、肉仔鸡后期和肉仔鸡前期配合饲料,DON和FB含量最高的是肉仔鸡前期配合饲料,而ZON含量最高的是肉仔鸡后期配合饲料,不同品种肉禽配合饲料中4种霉菌毒素含量均差异不显著(P0.05);从不同规模饲料厂来看,大规模饲料厂(年产量10万t)的饲料产品的污染水平比小规模饲料厂(年产量2万~5万t)低,但是不同规模饲料厂肉禽配合饲料中4种霉菌毒素的含量均差异不显著(P0.05)。由此可见,我国西南地区肉禽配合饲料普遍受到AFB_1、DON、ZON和FB的污染,其中AFB_1的超标率较高,4种霉菌毒素在不同地区、不同品种和不同饲料厂规模的饲料产品中的含量之间存在差异。     

脱氧雪腐镰刀菌烯醇的代谢特征

脱氧雪腐镰刀菌烯醇(DON)对以谷物为基础的食物和饲料的污染是一个全球性问题,严重危害了人和动物的健康。DON在人和动物体内的代谢特征是开展DON暴露评估、毒性作用机制和干预技术等研究的基础。近年来有关DON的吸收、分布、代谢和排泄等毒物动力学的研究引起了国内外广泛关注。本文将DON代谢特征的最新进展进行了全面的综述。     

Deoxynivalenol-contaminated wheat in swine diets

Two studies were conducted using Fusarium graminearum-infected (scabby) wheat containing 6.8 ppm deoxynivalenol (DON), commonly called vomitoxin, substituted for normal wheat in starter pig diets to give varying levels of DON. After 3 wk on experimental treatments, one-half of the pigs in trial one were sacrificed to evaluate the effects of DON on heart, kidney, spleen and liver. Analyses for DON residues in these tissues were also performed. The remaining 16 pigs were placed on a conventional diet for 4 wk to evaluate effects of DON on subsequent animal performance. A different sample of scabby wheat containing 4.9 ppm of DON was substituted for sorghum grain in growing-finishing pig diets to give varying concentrations of DON. At the end of the 42-d feeding period, eight pigs were slaughtered to evaluate the effects of DON on selected tissues. Results of the three trials suggest that feed intake was reduced when DON concentrations in the swine diets neared or exceeded 1 ppm. No apparent signs of disease, including vomiting, were observed in experimental animals. Histological evaluation revealed no significant lesions or abnormalities related to DON ingestion in tissues examined. Traces of DON (8 to 28 ppb, wet weight) were found in kidney, liver, spleen and heart of starter pigs consuming the diets containing DON up to time of slaughter. No DON was found in tissues of growing-finishing pigs that were withdrawn from feed about 12 h before slaughter.     

Development of a monoclonal antibody against deoxynivalenol for magnetic nanoparticle-based extraction and an enzyme-linked immunosorbent assay

Monoclonal antibody (mAb, NVRQS-DON) against deoxynivalenol (DON) was prepared. DON-Ag coated enzyme linked immunosorbent assay (ELISA) and DON-Ab coated ELISA were prepared by coating the DON-BSA and DON mAb. Quantitative DON calculation ranged from 50 to 4,000 ng/mL for DON-Ab coated ELISA and from 25 to 500 ng/mL for DON-Ag coated ELISA. 50% of inhibitory concentration values of DON, HT-2, 15-acetyl-DON, and nivalenol were 23.44, 22,545, 5,518 and 5,976 ng/mL based on the DON-Ab coated ELISA. Cross-reactivity levels of the mAb to HT-2, 15-acetyl-DON, and nivalenol were 0.1, 0.42, and 0.40%. The intra- and interassay precision coefficient variation (CV) were both <10%. In the mAb-coated ELISA, mean DON recovery rates in animal feed (0 to 1,000 µg/kg) ranged from 68.34 to 95.49% (CV; 4.10 to 13.38%). DON in a buffer solution (250, 500 and 1,000 ng/mL) was isolated using 300 µg of NVRQS-DON and 3 mg of magnetic nanoparticles (MNPs). The mean recovery rates of DON using this mAb-MNP system were 75.2, 96.9, and 88.1% in a buffer solution spiked with DON (250, 500, and 1,000 ng/mL). Conclusively we developed competitive ELISAs for detecting DON in animal feed and created a new tool for DON extraction using mAb-coupled MNPs.     

Short‐term ingestion of deoxynivalenol in naturally contaminated feed alters piglet performance and gut hormone secretion

The mycotoxin deoxynivalenol (DON) generally exists in cereals and affects human and animal health. The aim of this study is to analyze the impacts of DON in naturally contaminated feed on piglet growth performance and intestinal hormone secretion in the short term. We randomly divided 5‐week‐old piglets into four groups: Control, DON 1,000, DON 2,000 and DON 3,000 groups. Piglets received a feed naturally contaminated with DON (approximately 400, 1,000, 2,000 or 3,000 μg/kg) for 21 days. Body weight showed no significant difference following exposure to DON. The balance of anti‐oxidation and oxidation was disrupted by DON after 21 days. The concentration of tumor necrosis factor‐alpha (TNF‐α) and cyclooxgenase‐2 (COX‐2) significantly increased (p < .001) in all DON‐treated groups. Gut anorexigenic hormone secretion of peptide YY (PYY) and cholecystokinin (CCK) had a time‐ and dose‐dependent relationship with DON exposure; however, there was no effect on orexigenic hormone ghrelin secretion. Changes of histomorphology in the jejunum were observed in DON‐treated groups, including villi flattening and fusion, and apical necrosis of villi. These results indicated that DON could suppress piglet growth performance and alter gut hormone secretion in the short term.     

Feeding trials with vomitoxin (deoxynivalenol)-contaminated wheat: effects on swine, poultry, and dairy cattle

Nutritional and toxicologic feeding trials with 3 species of farm animals demonstrated that decreased feed consumption and reduced weight gains in pigs are the main effects of ingestion of a diet with low vomitoxin (deoxynivalenol; DON) content, eg, 2 mg of DON/kg of feed, ie, 2 ppm. The feeding trials indicated that swine can ingest up to 2 mg of DON/kg of feed without serious adverse effects. Poultry can tolerate at least 5 mg of DON/kg feed. In fact, at concentrations up to 5 mg of DON/kg feed, some beneficial effects on poultry were observed. In dairy cattle, feed consumption decreased slightly when a wheat-oats diet containing 6 mg of DON/kg was fed at the rate of 1% of body weight/day, with hay offered ad libitum. In surveys of Canadian grains carried out during the past 3 years, the DON content (maximum of 8.5 mg/kg) in eastern Canadian wheats probably was not high enough to account for reports of feed refusal, vomiting, and reproductive problems in livestock operations. This conclusion is based partly on the fact that even at the highest concentrations of DON found in wheat, formulated diets comprise, at maximum, about 70% to 80% wheat. Consequently, the actual DON content of diets fed to farm animals would be much lower.