DON、ZEA对免疫的影响及互作效应研究进展

玉米赤霉烯酮(ZEA)和呕吐毒素(DON)是镰刀菌的有毒次生代谢产物,过量能抑制动物机体的免疫功能,造成动物生长速度减缓、繁殖性能降低、抗病能力下降,疫苗免疫效果不理想或免疫失败,造成严重的经济损失。同时这两种毒素间可能产生协同作用增加对免疫功能的抑制作用。本文综述了近几年国内外学者对ZEA和DON造成动物免疫系统抑制及其互作效应的研究进展。     

镰刀菌毒素对母猪繁殖性能的影响及其作用途径

镰刀菌毒素玉米赤霉烯酮(zearalenonc,ZEA)和脱氧雪腐镰刀菌烯醇(deoxynivalenol,DON)是普遍存在于饲料中的优势污染霉菌毒素.ZEA具有雌激素样作用,可通过影响颗粒细胞激素的分泌和细胞增殖、干扰卵母细胞减数分裂的正常进行,降低卵母细胞质量,进而影响初情期前母猪的发情和妊娠母猪的繁殖性能.体内、外研究均发现DON具有降低卵母细胞和胚胎发育的能力.尽管没有临床症状,但组织病理学发现,饲喂含高浓度镰刀菌污染的小麦将导致妊娠母猪脾脏和肝脏的损伤,导致胎儿肝糖原升高和线粒体损伤.初情期前的小母猪对浓度DON>ZEA的饲粮较妊娠母猪更为敏感.镰刀菌毒索还会增加泌乳母猪的断奶-发情间隔时间.     

ZEA、DON及其联合作用对李斯特菌感染小鼠血清免疫相关细胞因子的影响

旨在探究玉米赤霉烯酮(ZEA)、脱氧雪腐镰刀菌烯醇(DON)及其联合作用对细菌感染动物防御能力的影响。试验以小鼠为对象，研究了低剂量的ZEA、DON对李斯特菌感染小鼠血清中免疫相关因子的变化。试验分别设空白对照组(Con)、李斯特菌组(Lis)、10 mg/kg ZEA+李斯特菌组(ZEA+Lis)、1 mg/kg DON+李斯特菌组(DON+Lis)、10 mg/kg ZEA+1 mg/kg DON+李斯特菌组(ZEA+DON+Lis),染毒方式为灌胃，细菌感染方式为尾静脉注射，剂量5×10⁴ CFU。在试验结束后，用抗体芯片技术检测小鼠血清中免疫相关细胞因子的水平。结果显示，与Con组相比，Lis组免疫细胞因子如白介素IL-1β、IL-12P40/P70,集落刺激因子MCSF,趋化因子MIG皆显著升高(P<0.05)。与Lis组相比，ZEA+Lis组IL-1β显著下降(P<0.05),基质金属蛋白酶TIMP-1显著上升(P<0.05);DON+Lis组IL-1β、IL-12P40/P70和MCSF显著下降(P<0.05),趋化因子BLC...     

玉米赤霉烯酮和脱氧雪腐镰刀菌烯醇对动物毒性的研究进展

玉米赤霉烯酮(ZEA)和脱氧雪腐镰刀菌烯醇(DON)是镰刀菌产生的毒素,广泛存在于霉变的玉米、小麦、大麦、燕麦和高粱等谷物中。自然条件下ZEA和DON经常混合污染饲粮、饲料原料乃至人类的食物,由于其高发生率和高毒性已严重威胁畜禽生产和人类健康,造成严重的经济损失和生命安全威胁。本文综述了ZEA和DON及其联合作用的生殖毒性、肠道毒性、免疫毒性、遗传毒性及致癌性,以期提高人们对其毒性的认识,避免畜禽养殖过程中ZEA和DON的毒害。     

脱氧雪腐镰刀菌烯醇、玉米赤霉烯酮及其联合染毒对小鼠肝脏功能及肝细胞凋亡的影响

为探讨脱氧雪腐镰刀菌烯醇(DON)、玉米赤霉烯酮(ZEA)及其联合染毒对小鼠肝脏功能和肝脏细胞凋亡的影响,成年雌性昆明小鼠360只,体质量(20±1)g,随机分为9组,腹腔单独或联合注射(每隔24 h注射1次,连续4次)不同浓度的镰刀菌素(DON 1.5,2.5 mg/kg;ZEA 20,30 mg/kg)。于感染后0,3,5,8,12 d测定小鼠肝脏AST、ALT的活性和TP、ALB的含量;3,5,8 d测定肝细胞凋亡率的变化。结果表明,DON、ZEA单独或联合染毒均显著提高小鼠肝脏AST、ALT活性及肝细胞凋亡率(P0.01或P0.05),显著降低TP、ALB含量(P0.05);联合染毒组与相应单一染毒组相比差异显著(P0.01或P0.05),呈现明显的剂量-效应关系。联合染毒具有亚加性效应,以2.5mg/kg DON与30 mg/kg ZEA联合染毒所呈现的亚加性效应更明显。     

ZEA、DON及其联合染毒对CTLL-2细胞因子分泌的影响

为研究镰刀菌毒素玉米赤霉烯酮（ZEA）、脱氧雪腐镰刀菌烯醇（DON）及其联合作用对动物免疫功能的影响,试验以CTLL-2细胞（细胞毒性T淋巴细胞株）为材料,用不同浓度的ZEA （0、5、10、20 μg/mL）、DON （0、0.5、1、2 μg/mL）及联合（空白组、5 μg/mL ZEA、0.5 μg/mL DON、5 μg/mL ZEA＋0.5 μg/mL DON）处理CTLL-2细胞48 h,采用ELISA法检测了细胞内及培养上清液中颗粒酶B （GZMB）、穿孔素（PFP）、干扰素γ（IFN-γ）和肿瘤坏死因子α（TNF-α）等细胞因子的含量。结果显示,ZEA、DON能够降低CTLL-2细胞胞内及培养上清液中PFP、GZMB、IFN-γ的浓度,增加TNF-α浓度,染毒组与对照组相比均有显著或极显著差异（P＜0.05;P＜0.01）,且均呈剂量效应关系;ZEA、DON联合染毒表现为加性效应。结果表明,ZEA、DON及其联合作用可通过影响免疫细胞因子的分泌,降低免疫细胞杀伤活力,间接影响机体体液免疫和细胞免疫的负调节,从而导致动物机体免疫机能下降。     

玉米赤霉烯酮对动物繁殖性能的毒性作用及其机制

玉米赤霉烯酮（ZEA）一种由镰刀菌属产生的次级代谢物，化学结构与内源性雌激素相似，因此，ZEA可通过与雌激素竞争性结合雌激素受体，导致动物机体生殖激素代谢紊乱，诱发生殖器官形变及功能障碍，严重危害动物繁殖系统，解决ZEA污染问题己经成为当务之急。本文对ZEA的理化特性、毒性作用等进行综述，以期为有效缓解ZEA毒性及提高动物繁殖性能、促进畜牧业健康发展提供理论依据。     

饲料中DON的污染及其对畜禽的危害

脱氧雪腐镰刀菌烯醇(DON)是谷物受镰刀菌污染而产生的一种常见的霉菌毒素。脱氧雪腐镰刀菌烯醇经动物吸收后能快速地排泄而在动物组织中很少残留。但该毒素对动物的采食量以及生长性能有一定影响。     

基于体外细胞模型的霉菌毒素毒性评价

霉菌毒素是由多种真菌产生的次级代谢产物,广泛存在于食品和饲料中。霉菌毒素污染的粮食和饲料会给畜牧业生产和畜产品质量安全带来极大隐患。研究霉菌毒素致毒机理,为今后研究其对动物及人的影响开展更深入更全面的研究提供理论依据。细胞模型作为一种常用的体外试验方法广泛用于毒理学研究中。本文简述了黄曲霉毒素B_1(AFB_1)、赭曲霉毒素A(OTA)、脱氧雪腐镰刀菌烯醇(DON)、玉米赤霉烯酮(ZEA)和展青霉素(PAT)的一般特性,并综述了利用细胞模型进行AFB_1、OTA、DON、ZEA和PAT毒性、联合毒性及致毒机理研究的进展。     

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。     

黄曲霉毒素B1、玉米赤霉烯酮和呕吐毒素的累加细胞毒性研究

由于饲料中多种霉菌毒素并存的几率比较高，本研究以仔猪肠上皮细胞（IPEC-J2）为模型，研究黄曲霉毒素B1（AFB1）、玉米赤霉烯酮（ZEA）和呕吐毒素（DON）的叠加细胞毒性。细胞毒性试验选用AFB1、ZEA和DON三种毒素作为响应面Box-Behnke设计的三个因素，以AFB1：10、20、30 μg/L，ZEA：150、300、450 μg/L，DON：500、1000、1500 μg/L作为Box-Behnke设计的三个编码水平。利用响应面设计构建得到17组复合霉菌毒素组合，以其对IPEC-J2细胞活力的影响作为参考指标，得到对细胞损伤程度最高和最低的霉菌毒素添加比例。结果表明：经方程预测后，得到细胞活力最低（霉菌毒素毒性最高）的AFB1、ZEA和DON组合为30、150 μg/L和1500 μg/L，经测定细胞活力为32.32%|得到细胞活力最高（霉菌毒素毒性最低）的AFB1、ZEA和DON组合为10、150 μg/L和600 μg/L，经测定细胞活力为53.01%。该结果为多种霉菌毒素叠加毒性的研究提供了依据。 [关键词] IPEC-J2细胞|黄曲霉毒素B1|玉米赤霉烯酮|呕吐毒素|细胞毒性     

Zearalenone and deoxynivalenol mycotoxicosis in dairy cattle herds

Mycotoxin contaminations pose a growing problem in animal production from the economic and toxicological point of view. Clinical symptoms of mycotoxicosis are relatively unspecific, making the disease difficult to diagnose. This study presents a clinical case of dairy cattle infected with natural mycotoxins produced by fungi of the genus Fusarium (zearalenone [ZEA] and deoxynivalenol [DON]) in eastern Poland. In dead and infected cows, the presence of ZEA and DON was determined in the blood serum, significant changes were observed in blood morphological and biochemical profiles, extravasations and bowel inflammations were also observed. The results reported testify to an acute autoimmune process in the intestines as well as immunosuppression.     

Effects of ZEA,DON and Their Combined Effects on the Secretion of Cytokines in CTLL-2 Cells

To analyze the effects of ZEA or/and DON on the immunologic function,CTLL-2 cell was used as experimental materials. After exposing the CTLL-2 cell to different concentrations of ZEA (0,5,10,20 μg/mL),DON (0,0.5,1,2 μg/mL) and ZEA+DON (blank group,5 μg/mL ZEA,0.5 μg/mL DON,5 μg/mL ZEA+0.5 μg/mL DON) for 48 h,the concentration of GZMB,PFP,IFN-γ and TNF-α in CTLL-2 cell and supernatant fluid were detected by ELISA method. The result showed that DON and ZEA could reduce the concentration of PFP,GZMB and IFN-γ in the CTLL-2 cells and the culture supernatant fluids,and increase the concentration of TNF-α. The intoxicated group had significant or extremely significant difference compared to control group (P <0.05;P <0.01),which showed the dose effect. The group exposed to the combined of ZEA and DON showed an additive effect. The result indicated that ZEA,DON and the two combined could reduce the killing activity of immunological cell by affecting the secretion of immunological cytokines, and indirectly affect the negative feedback regulation of humoral immunity and cellular immunity,which led to the decline of immune function in animals.     

Occurrence of mycotoxins in feed ingredients and complete feeds obtained from the Beijing region of China

Background

The current study was carried out to provide a reference for the control of mycotoxin contamination in feed ingredients and complete feeds for swine.

Methods

A total of 55 feed ingredients, including 14 corn, 13 wheat bran, 11 soybean meal and 17 dried distillers grains with solubles (DDGS) as well as 76 complete swine feeds including 7 creep feeds, 14 starter feeds, 14 grower feeds, 18 grower-finisher feeds, 10 gestating sow feeds, and 13 lactating sow feeds were randomly collected from 15 swine farms located in the Beijing region of China from July to August 2011. Immunoaffinity clean-up, using High-Performance Liquid Chromatography (HPLC) in combination with UV or Fluorescence Detection, was used for quantitative analysis of aflatoxin B₁ (AFB₁), deoxynivalenol (DON), zearalenone (ZEA) and ochratoxin A (OTA) in the ingredients and complete feeds.

Results

DON and ZEA were the most prevalent mycotoxins found. DON was detected at percentages of 93, 92, 54, 100 and 97% with a mean level of 1.01, 0.44, 0.05, 1.36 and 0.65 ppm in the samples of corn, wheat bran, soybean meal, DDGS and complete feeds, respectively. The detected percentages of ZEA were 100, 100, 54, 100 and 100 with mean levels of 109.1, 14.9, 9.2, 882.7 and 58.9 ppb in the same samples. In the wheat bran and soybean meal samples, the content of all four mycotoxins were below the maximum limits set by Chinese regulations while the percentage of samples that exceeded regulatory limits were 7, 57 and 7% for corn, and 7, 14 and 3% for the complete feeds for AFB₁, DON and OTA respectively. DDGS showed the most serious mycotoxin contamination and the percentage of samples that exceeded regulatory limits were 6, 88 and 41%, for AFB₁, DON and ZEA, respectively.

Conclusions

This paper is the first to present data on the natural occurrence of AFB₁, DON, ZEA and OTA in ingredients and complete feeds obtained from swine farms in China’s Beijing region. The data shows that feed ingredients and complete swine feeds obtained from these farms are most often contaminated with DON followed by contamination with AFB₁ and ZEA.     

Simultaneous detection of multiple mycotoxins in broiler feeds using a liquid chromatography tandem-mass spectrometry

Mycotoxins are secondary fungal metabolites that are typically present in grain and feed ingredients used for animal feeds. An analytical method using LC-ESI-MS/MS was developed to quantify nine mycotoxins, consisting of aflatoxin B₁ (AFB₁), AFB₂, AFG₁, AFG₂, T-2 toxin, deoxynivalenol (DON), nivalenol (NIV), zearalenone (ZEA) and ochratoxin A (OTA) in broiler feeds. In total, 100 samples of broiler feeds were collected from poultry farms in Central Thailand. The survey found that AFB₁ and ZEA were the most prevalent mycotoxins in the feed samples at percentages of 93% and 63%, respectively. The limit of detections (LODs) of investigated mycotoxins was 0.20–0.78 ng/g. AFB₂, DON, AFG₁, NIV and T-2 toxin were also detectable at low contamination levels with percentages of 20%, 9%, 7%, 5% and 1%, respectively, whereas OTA and AFG₂ were not detected in any of the feed samples. These results suggest that there is a very low level of risk of the exposure to mycotoxins in feeds obtained from broiler farms in Central Thailand.     

Dietary origin of mycotoxins with estrogenic potential and possible health implications to female dogs

In Poland, occurrence of toxigenic fungi in cereals, foods, feeds and their components as well as mycotoxins accumulation in such material has been studied by numerous teams including our research group for over thirty years since 1969. Mostly cereal kernels and feeds have been examined for presence of toxigenic fungi, their toxigenic potential and natural contamination with mycotoxins. Ochratoxin A, deoxynivalenol, nivalenol and moniliformin were found to be significant contaminants of agricultural products in high percentage of cereal grain samples. The profile of toxic metabolites was similar but the concentration levels of the toxins were lower when compared to already published data of the same climate zone. Zearalenone (ZEA), a nonsteroidal mycotoxin with estrogen-like activity, is synthesized by molds (Fusarium) commonly contaminating poorly stored agricultural products and foodstuffs. Since in the course of examinations and during surgical procedures performed in dogs, ovarian cysts were detected and because frequently this is the first stage of the endometrica pyometra complex (EPC) found in approximately 30% of the females we assume that both factors, mycotoxins (ZEA) and pathological aberrations are possibly related in these animals. Similar activity of the toxin (possibly present in pelleted dog feed) and effects including infertility of female dogs is speculated with indication and suggestion on necessity of additional studies on the problem.     

脱氧雪腐镰刀菌烯醇与玉米赤霉烯酮联合暴露对体外培养鸡脾脏淋巴细胞内环境稳态的影响

本试验旨在研究脱氧雪腐镰刀菌烯醇(DON)与玉米赤霉烯酮与(ZEA)联合暴露对体外培养鸡脾脏淋巴细胞内环境稳态的影响。分别以0.012 50μg/mL DON+0.006 25μg/mL ZEA、0.050μg/mL DON+0.025μg/mL ZEA、0.2μg/mL DON+0.1μg/mL ZEA、0.8μg/mL DON+0.4μg/mL ZEA对体外培养鸡脾脏淋巴细胞进行联合暴露培养,48 h后测定细胞膜ATP酶(Ca~(2+)-ATP酶、Na~+/K~+-ATP酶)活性以及细胞内pH、Ca~(2+)水平和钙调蛋白(CaM)的mRNA表达水平。同时设不添加毒素的空白对照组。结果表明:添加毒素的各试验组间,细胞内Ca~(2+)水平、CaM mRNA表达水平随毒素浓度的升高而增加,且添加毒素的各试验组均显著或极显著高于空白对照组(P0.05或P0.01)。细胞内pH以及细胞膜Ca~(2+)-ATP酶与Na~+/K~+-ATP酶活性均随毒素浓度的升高而降低,且添加毒素的各试验组均显著或极显著低于空白对照组(P0.05或P0.01)。由此得出,DON、ZEA联合暴露导致体外培养鸡脾脏淋巴细胞内酸化、离子平衡失调等一系列细胞内环境稳态失衡,且呈剂量依赖性。     

The Fusarium toxins deoxynivalenol (DON) and zearalenone (ZON) in animal feeding

The contamination of cereal grains with toxic secondary metabolites of fungi, mycotoxins, is a permanent challenge in animal nutrition as health and performance of the animals may be compromised as well as the quality of animal derived food. Therefore the present article reviews the issue of mycotoxins in animal nutrition. As the Fusarium toxins deoxynivalenol (DON) and zearalenone (ZON) are of particular importance under the production conditions in central Europe and Germany, with respect to their frequent occurrence in toxicologically relevant concentrations, special emphasis is layed on those mycotoxins. The effects of DON and ZON on susceptible animals as well as management strategies to cope with the contamination of grain with those toxins are reviewed.     

Effects of Fusarium toxins on growth, humoral immune response and internal organs in weaner pigs, and the efficacy of apple pomace as an antidote

A feeding trial using 220 weaner pigs which comprised two experimental series was conducted to investigate the effects of diets contaminated with the Fusarium toxins deoxynivalenol (DON) and zearalenone (ZON) and to test the hypothesis that apple pomace acts as an antidote to these mycotoxins. Two diets without contaminated wheat, containing either no pomace or 8% pomace, and two diets with naturally contaminated wheat (3.2 mg DON and 0.06 mg ZON, and 2.1 mg DON and 0.25 mg ZON per kg diet in series 1 and 2 respectively), containing either no pomace or 8% pomace were fed ad libitum for 5 weeks. Mycotoxin exposure lowered feed intake (p < 0.01) and growth (p = 0.05), and tended to decrease the energy conversion ratio (p = 0.06). Although the intake of apple pomace did not increase feed intake, it increased the growth rate (p = 0.04), mainly by restoring growth in the presence of mycotoxins (p = 0.08 for the interaction mycotoxin x pomace). In the first experimental series, the animals were immunized with a parvovirus vaccine. The percentage of seroconverting animals did not differ between the treatments (p = 0.56), which indicates that DON did not affect the humoral immune response. In the second experimental series, female piglets fed the contaminated diets had heavier uteri than piglets fed the uncontaminated diets (p < 0.01), regardless of pomace supplementation. The results show that pomace may alleviate the negative effect of DON on growth but does not counteract the hormonal effects of ZON.