蒙脱石和凹凸棒石对霉菌毒素吸附性能的研究

试验将蒙脱石和凹凸棒石分别添加到含有黄曲霉毒素B₁(AFB₁)、玉米赤霉烯酮和T-2毒素的人工胃液或人工肠液中,探讨2种矿物对霉菌毒素的吸附作用。结果表明,蒙脱石和凹凸棒石对AFB₁、玉米赤霉烯酮、T-2毒素的吸附均在1 h达到平衡;钠基蒙脱石对AFB₁和T-2毒素的吸附率高于钙基蒙脱石和凹凸棒石,吸附率分别为96.8%、38%;蒙脱石和凹凸棒石对玉米赤霉烯酮的吸附率均小于10%。pH对蒙脱石和凹凸棒石吸附霉菌毒素影响显著(P<0.05),pH 5时钙基蒙脱石对AFB₁的吸附率显著高于pH 3、pH 7时(P<0.05),为90.1%;蒙脱石和凹凸棒石对玉米赤霉烯酮的吸附效果在pH 3时较佳,对T-2毒素的吸附效果在pH 7时显著高于pH 3、pH 5时(P<0.05)。蒙脱石和凹凸棒石对吸附的霉菌毒素均存在解吸现象,其中AFB₁和玉米赤霉烯酮解吸明显。蒙脱石和凹凸棒石对霉菌毒素的吸附作用使其成为重要的吸附剂,然而作为吸附剂的同时不能忽视霉菌毒素的解吸现象,综合考虑吸附与解吸2种现象以便在生产实践中更好的脱除霉菌毒素。     

一起玉米赤霉烯酮及呕吐毒素中毒引起猪繁殖障碍的病例报告

2012年4月,山东某规模猪场暴发疾病,母猪受胎率、产仔数、健仔数等繁殖性能指标显著下降,猪群表现出不同程度的霉菌毒素中毒症状。经初步调查,发现该猪场所饲喂的饲料被霉菌毒素污染,进一步采取原料玉米及饲料样品通过高效液相色谱法鉴定霉菌毒素种类及含量,结果显示,原料玉米中赤霉烯酮、呕吐毒素及烟曲霉毒素含量均超标。经更换饲料和采用脱霉剂后,母猪繁殖性能指标显著恢复。     

玉米赤霉烯酮对青年母猪子宫发育、生长激素分泌及其受体分布与表达的影响

本试验旨在研究玉米赤霉烯酮(ZEA)对青年母猪子宫发育、生长激素(GH)分泌及其受体(GHR)分布与表达的影响.选择胎次和体重[(23.20±0.68)kg]相近的长×大二元青年母猪48头,将其随机分为4组,每组12个重复,每个重复1头.对照组(CON组)饲喂基础饲粮,试验组(T1、T2、T3组)饲喂在基础饲粮中分别添...     

玉米赤霉烯酮诱导山羊子宫内膜基质细胞凋亡的研究

玉米赤霉烯酮(zearalenone,ZEN)是由镰刀菌产生的一种霉菌毒素,具有细胞毒性和雌激素活性,会对生殖系统、泌尿系统和消化系统等产生严重毒性影响.目前,ZEN对山羊子宫内膜基质细胞(endometrial stromal cells,ESCs)凋亡的潜在作用仍不清楚.本研究通过体外培养山羊永生化ESCs,采用C...     

Detection of estrogenically active substances in diets for sows by an in vitro bioassay supported by HPLC analysis

There is considerable evidence that exogenous estrogenic compounds can have adverse effects on fertility. The main reason cited in literature for hyperestrogenism in pigs is contamination of feedstuffs by the mycotoxin zearalenone (Boehm, 2000), but further estrogenically active substances might also be involved in cases of impaired fertility with symptoms like enlarged, red-coloured vulvae in piglets, irregular estrus cycles and anestrus of sows (Bennetts et al., 1946; Drane et al., 1981). It is well known that soy used in diets for pigs as a main protein source contains phytoestrogens. Amongst them, isoflavones like genistein and daidzein are of particular interest. Aim of this study was to optimize and use an established bioassay (Kluczka, 2003) to determine estrogenic activity in feedstuffs for pigs related to isoflavones and further substances with estrogenic potential. This bioassay is a reporter gene assay based on stably transfected human embryonal kidney cells (HEK 293) that contains either alpha or beta estrogen receptor (alpha- or beta-HEK). The estrogenic activity measured in the luciferase assay was expressed in estradiol-equivalents (EEQ) and the results were compared with the isoflavone content (genistein, daidzein) obtained by chemical analysis using high performance liquid chromatography-Ultraviolet (HPLC-UV). Mean estrogenic activity in diets fed to sows in herds with altered fertility was 275.8 microg EEQ/kg feed in alpha-HEK cells and 295.0 microg EEQ/kg feed in beta-HEK cells. Feedstuffs from herds without any altered fertility showed an average estrogenic activity of 204.9 microg EEQ/kg feed in alpha-HEK and 213.3 microg EEQ/kg feed in beta-HEK. The estrogenic activity was strongly related to the concentration of the isoflavones (alpha-HEK, r(2)=0.9488; beta-HEK, r(2)=0.9427). Clinically relevant zearalenone concentrations (>50-150 microg/kg feed) displayed estrogenic effects in the bioassay that did not differ significantly from those caused by high isoflavone concentration because of the use of soy as protein source.     

姜黄素通过SIRT1/FOXO1通路缓解玉米赤霉烯酮诱导的猪肾上皮细胞氧化损伤

【目的】探究姜黄素(Cur)对玉米赤霉烯酮(ZEA)诱导猪肾上皮细胞(PK-15)氧化损伤的保护作用,并基于SIRT1/FOXO1信号通路阐明其作用机制,为姜黄素的兽医临床应用提供依据。【方法】试验分为5组：对照组、ZEA组(36.55μg·mL^-1 ZEA)、Cur 6.25组(36.55μg·mL^-1 ZEA+6.25μmol·L^-1 Cur)、Cur 12.5组(36.55μg·mL^-1 ZEA+12.5μmol·L^-1 Cur)、Cur 25组(36.55μg·mL^-1 ZEA+25μmol·L^-1 Cur);通过MTT法测定ZEA的半数抑制浓度和Cur对PK-15细胞的最大安全浓度;使用倒置显微镜观察PK-15细胞的形态变化;采用试剂盒检测细胞内活性氧(ROS)、超氧化物歧化酶(SOD)、过氧化氢酶(CAT)以及丙二醛(MDA)的水平;qRT-PCR检测细胞SIRT1、FOXO1、CAT、Mn-SOD的mRNA水平;West...     

白藜芦醇对玉米赤霉烯酮致小鼠肝脏氧化损伤及炎症的保护作用

为探究白藜芦醇（RSV）对玉米赤霉烯酮（ZEA）中毒小鼠肝脏损伤是否具有保护作用,试验将40只清洁级雄性BALB/c小鼠随机分为5组：对照组（生理盐水）、ZEA组（40 mg/kg）、不同浓度的RSV （50、100或200 mg/kg）与ZEA （40 mg/kg）共处理组,每组8只,各组均灌胃给药,试验期12 d。试验结束后采集小鼠肝脏样品,计算肝脏系数,采用苏木素-伊红（HE）染色和免疫组织化学染色法观察各组肝脏病理变化;检测肝脏NF-κB蛋白表达;比色法检测肝脏组织中丙二醛（MDA）含量、超氧化物歧化酶（SOD）和过氧化氢酶（CAT）活性及血清中谷丙转氨酶（ALT）、谷草转氨酶（AST）和乳酸脱氢酶（LDH）活性,ELISA法检测血清中白细胞介素-6（IL-6）、肿瘤坏死因子-α（TNF-α）和IL-1β含量。结果显示,与对照组相比,ZEA组小鼠肝组织发生明显病理学变化;与ZEA组相比,不同浓度RSV与ZEA共处理组小鼠肝脏组织病理学变化都有所减轻。免疫组织化学结果显示,与对照组相比,ZEA组肝脏NF-κB蛋白表达增多;与ZEA组相比,不同浓度的RSV与ZEA共处理组肝脏NF-κB蛋白表达均有下降。与对照组相比,ZEA组肝脏系数和肝脏组织MDA含量极显著升高（P<0.01）,肝脏组织SOD和CAT活性显著或极显著降低（P<0.05;P<0.01）,血清中AST、ALT和LDH活性,IL-6、TNF-α和IL-1β含量均极显著升高（P<0.01）。与ZEA组相比,不同浓度RSV与ZEA共处理组肝脏组织CAT活性显著或极显著升高（P<0.05;P<0.01）,血清中AST、ALT和LDH活性及IL-6和IL-1β含量显著或极显著降低（P<0.05;P<0.01）;50 mg/kg RSV与ZEA共处理组肝脏组织SOD活性和血清中TNF-α含量分别显著升高（P<0.05）和极显著降低（P<0.01）;100和200 mg/kg RSV与ZEA共处理组肝脏系数和肝脏组织MDA含量显著或极显著降低（P<0.05;P<0.01）。结果表明,ZEA对小鼠肝脏有严重的氧化及炎症损伤作用,RSV对ZEA中毒的肝损伤具有一定保护作用,尤其以100 mg/kg RSV保护效果最佳。     

自然越冬过程中冬小麦体内玉米赤霉烯酮含量的变化

用放射免疫分析法首次测定了冬小麦自然越冬期间不同部位中玉米赤霉烯酮含量。发现越冬冬小麦的分蘖节中玉米赤霉烯酮含量呈双峰曲线,10月底和1月初分别出现最高值。根尖中的含量与分蘖节中的含量变化基本同步,但前期无明显峰值。在1月初根尖和分蘖节同时出现峰值时,根尖中的含量约为分蘖节中含量的10倍。02-10以后,各部位含量的均降至较低水平。说明冬小麦体内玉米赤霉烯酮含量变化与春化过程密切相关。鉴于根尖和分蘖节含量远高出其他部位,推测分生组织是玉米赤霉烯酮生物合成的活跃部位。     

Toxigenic Fusarium Species and Mycotoxins Associated with Maize Ear Rot in Europe

Several Fusarium species occurring worldwide on maize as causal agents of ear rot, are capable of producing mycotoxins in infected kernels, some of which have a notable impact on human and animal health. The main groups of Fusarium toxins commonly found are: trichothecenes, zearalenones, fumonisins, and moniliformin. In addition, beauvericin and fusaproliferin have been found in Fusarium-infected maize ears. Zearalenone and deoxynivalenol are commonly found in maize red ear rot, which is essentially caused by species of the Discolour section, particularly F. graminearum. Moreover, nivalenol and fusarenone-X were often found associated with the occasional occurrence of F. cerealis, and diacetoxyscirpenol and T-2 toxin with the occurrence of F. poae and F. sporotrichioides, respectively. In addition, the occurrence of F. avenaceum and F. subglutinans usually led to the accumulation of moniliformin. In maize pink ear rot, which is mainly caused by F. verticillioides, there is increasing evidence of the wide occurrence of fumonisin B₁. This carcinogenic toxin is usually found in association with moniliformin, beauvericin, and fusaproliferin, both in central Europe due to the co-occurrence of F. subglutinans, and in southern Europe where the spread of F. verticillioides is reinforced by the widespread presence of F. proliferatum capable of producing fumonisin B₁, moniliformin, beauvericin, and fusaproliferin.     

不同水平玉米赤霉烯酮对断奶仔猪血清代谢产物和肝肾组织病理学影响

目的】玉米赤霉烯酮（zearalenone, ZEA）是由谷物及其产品滋生禾谷镰刀菌产生的一种具有雌激素活性的真菌毒素。试验研究不同水平玉米赤霉烯酮污染日粮对断奶仔猪血清代谢产物、肝肾组织病理学和肝脏超微结构的影响。【方法】将20头健康三元（斯格×长×大）杂交断奶母猪（10.36±1.21）kg按照体重随机分为4个处理,仔猪采用试验笼单独饲养。对照组饲喂基础日粮,试验1、2和3组分别在基础日粮的基础上添加ZEA 1.1、2.0和3.2 mg·kg^-1。预饲期7 d,正式期18 d。试验结束后,对仔猪禁食12 h后进行前腔静脉空腹采血,分离血清,待测血清代谢产物含量。采血后,仔猪电击致死放血屠宰,切取肝脏和肾脏组织块迅速固定于10%的福尔马林溶液,待做组织切片检测。切取0.5 mm³大小的肝脏组织块,迅速用2.5%戊二醛磷酸盐缓冲液固定,待做电镜切片进行超微结构观察。【结果】与对照组相比,3.2 mg·kg^-1 ZEA处理组仔猪血清胆红素显著高于对照仔猪（P＜0.05）,而血清球蛋白和甘油三酯则显著低于对照组（P＜0.05）。随日粮ZEA水平的增加,血清球蛋白和甘油三酯呈一次线性降低（P＜0.05）。与对照组相比,1.1、2.0和3.2 mg·kg^-1 ZEA处理组肝细胞肿胀,颗粒变性。与对照组相比,2.0 和3.2 mg·kg^-1 ZEA处理组肾小管上皮细胞颗粒变性,管腔变窄,有些管腔内充满大量透明底状物或蛋白尿。2.0和3.2 mg·kg^-1 ZEA处理组肝细胞膜上可见自噬体和嗜中性白细胞。【结论】2.0 mg·kg^-1的ZEA足以诱导仔猪的肝肾毒性,此结果对人类健康和指导动物生产具有重要的借鉴意义。