高效液相色谱同步检测饲料中黄曲霉毒素B1、玉米赤霉烯酮及呕吐毒素的方法

本研究旨在建立同步检测饲料中黄曲霉毒素B_1、玉米赤霉烯酮及呕吐毒素的高效液相色谱(HPLC)法。样品用乙腈-水提取,经涡旋、高速离心,移取2 mL上清液加入28 mL含1%吐温-20的磷酸盐缓冲液(PBS,pH 7.0),过三合一免疫亲和柱净化,用2 mL甲醇洗脱;洗脱液经50℃浓缩氮气吹干后用50%甲醇-水复溶,采用高效液相色谱仪串联光化学衍生器、荧光检测器和紫外检测器进行检测。结果表明:黄曲霉毒素B_1标准品溶液浓度在2.5～50.0 ng/mL、玉米赤霉烯酮标准品溶液浓度在50～2 500 ng/mL、呕吐毒素标准品溶液浓度在250～5 000 ng/mL时线性关系良好,平均加标回收率为81.2%～92.3%,相对标准偏差(RSD)为4.3%～9.5%。采用该方法检测了4种不同饲料样品中的黄曲霉毒素B_1、玉米赤霉烯酮及呕吐毒素含量,所有样品均检测出1种以上霉菌毒素,说明饲料中霉菌毒素混合污染较为普遍。由此可见,本试验所建立的方法准确度和精密度高,稳定性好,可作为饲料中黄曲霉毒素B_1、玉米赤霉烯酮及呕吐毒素的同步检测方法。     

霉菌毒素与畜禽免疫抑制

1常见的霉菌和霉菌毒素 霉菌通常污染饲料或饲料原料,在其中生长并产生二级代谢产物——霉菌毒素。产毒霉菌主要有3个属,曲霉菌、青霉菌和镰刀菌,而霉菌毒素目前已发现超过350种。常见的霉菌毒素有黄曲霉毒素（AF）、玉米赤霉烯酮（ZEA）、T-2毒素、呕吐毒素（DON）、赭曲霉毒素（OT）、烟曲霉毒素（FUM）等。其中对猪危害最大的是黄曲霉毒素、玉米赤霉烯酮和呕吐毒素。家禽饲料中,自然状况下发生率最高且致害作用最严重的是黄曲霉毒素和单端孢霉烯族毒素。     

猪胃肠道食糜中黄曲霉毒素B_1和玉米赤霉烯酮检测方法的改进及其在霉菌毒素吸附剂吸附效果评价中的应用

本试验旨在建立测定猪胃和小肠食糜上清液中黄曲霉毒素B1和玉米赤霉烯酮含量的高效液相色谱(HPLC)法,并利用该方法评价霉菌毒素吸附剂分别在不同介质中对黄曲霉毒素B1和玉米赤霉烯酮的吸附效果。为消除食糜上清液中复杂组分对目标毒素检测的干扰,本试验对毒素提取方法、液相色谱的检测波长设置和流动相组成进行了优化。利用单浓度体外吸附试验评价了4种霉菌毒素吸附剂分别在水、猪胃和小肠食糜上清液介质中对黄曲霉毒素B1和玉米赤霉烯酮的吸附效果。结果表明:1)反应上清液经过1次正己烷和3次二氯甲烷提取,荧光激发波长和发射波长在0~9 min和9~14 min分别设定为360、440 nm和235、418 nm,乙腈/水流动相中乙腈比例控制在40%~60%时,本试验采用的HPLC仪对1.00~10 000.00 ng/m L黄曲霉毒素B1和20.00~5 000.00 ng/m L玉米赤霉烯酮具有良好的分离定量效果,线性相关系数分别为1.000和0.999;检出限分别为0.16和2.00 ng/m L;黄曲霉毒素B1和玉米赤霉烯酮日内精密度相对标准差分别为2.37%、4.50%;日间精密度相对标准差分别为2.74%、8.84%。黄曲霉毒素B1和玉米赤霉烯酮标准添加回收率分别为89.1%~110.3%、98.7%~104.1%。2)自制霉菌毒素吸附剂样品P3、M3和市场采购的霉菌毒素吸附剂产品Y1、Y2在猪胃食糜上清液介质中对黄曲霉毒素B1的吸附率依次为72.10%、84.18%、83.17%和66.01%;在猪小肠食糜上清液介质中的吸附率依次为78.15%、88.08%、88.12%和67.34%。4种吸附剂在胃食糜上清液介质中对玉米赤霉烯酮的吸附率依次为85.35%、18.41%、16.20%和12.98%;在猪小肠食糜上清液介质中的吸附率分别为39.75%、25.15%、21.40%和24.85%。综上,本试验建立的HPLC法可同时测定猪胃和小肠食糜上清液中的黄曲霉毒素B1和玉米赤霉烯酮,检测限和检测范围满足我国《猪饲料卫生标准》的要求。该方法可用于评价霉菌毒素吸附剂猪生理体液条件下对黄曲霉毒素B1和玉米赤霉烯酮的吸附效果。     

母猪玉米赤霉烯酮中毒的诊治

玉米赤霉烯酮,又称F-2毒素。系禾谷镰刀菌的一种代谢产物,属雌激素物质。研究证明玉米赤霉烯酮经饲料进入动物体内,主要侵害的是生殖器官,表现为雌激素效应。猪玉米赤霉烯酮中毒是由于猪采食了大量被产生F-2毒素的镰刀菌所污染的饲料而引起的。     

霉麦中黄曲霉的分离及其产毒的研究

从黑龙江省嫩江地区某农场1983年收获的小麦(发霉)中分离出黄曲霉,经产毒培养黄曲霉毒素B_1量为35.44 PPb。从产毒培养基中抽提的黄曲霉毒素B_1,进行鸭雏中毒试验,经剖检后肉眼观察及病理切片所见为黄曲霉中毒。验证该农场用此小麦饲喂猪大批死亡主要原因是由于黄曲霉素急性中毒所致。     

生物脱霉剂对黄曲霉毒素 B1 的作用研究

为了研究生物脱霉剂的脱霉效果,本试验测定了生物脱霉剂对黄曲霉毒素B1的吸附强度,同时采用全收粪试验检测了霉变饲料添加生物脱霉剂后,家畜粪便中黄曲霉毒素B1的排出率.结果表明,将黄曲霉毒素B1的浓度调整为2μg/g时,添加1.2‰的生物脱霉剂,可吸附98.34%的黄曲霉毒素B1,全收粪试验表明,在霉变饲料中添加1‰的生物脱霉剂,被吸附的黄曲霉毒素B1 随粪便的排出率为50.44%,添加2‰的生物脱霉剂,黄曲霉毒素B1的排出率为72.30%.     

玉米赤霉烯酮对公猪精液的影响

<正> 霉菌毒素对种猪群有影响,最常与母猪群有关,但也会危害公猪的生殖性能。最近,立陶宛动物科学研究所的研究人员研究了霉菌毒素解毒剂及其对公猪精液的影响。该饲料添加剂具有广谱活性,可降低霉菌毒素如黄曲霉毒素、赭曲霉毒素、单端孢菌素(T-2毒素、TH-2毒素)、雪腐镰刀菌烯醇、双乙酸基晗草烯醇等的吸收和生物转化,从而降低它们的生物利用率。在试验中,将体重150～155千克的10月龄立陶宛白公猪分为3组。对照组喂给无霉菌毒素的饲料,试验组给以含玉米赤霉烯酮0.57毫克/千克的饲料,第三种试验料则在饲料中按1千克/吨的比率添加解毒剂。在试验前10天,对公猪饲喂优质的饲料并训练其接受人工采精,评估精液的质量和数量参数。试验期间,各组公猪分别饲喂各自的饲料32天,每周采精一次。最后21天为恢复期,所有公猪均只是饲喂优质饲料,再次采集精液。     

黄曲霉毒素对养鸡生产的危害及预防

一、黄曲霉毒素对养鸡生产的危害黄曲霉毒素,是一种在紫外光照射下能发生强烈的特殊荧光的物质。目前已鉴定出其化学结构有 B_1、B_2、G_1、G_2等10多种。其中黄曲霉毒素 B_1在200℃高温、强酸、紫外线照射下都不能使之破坏。黄曲霉毒素以B_1为代表是毒性最大、致癌性很强的一种毒物,可诱发肝癌。黄曲霉毒素是黄曲霉和寄生曲霉的代谢产物。许多农产品,特别是玉米、花生、各种油饼类等因保管处理不当而发生霉变,都可被黄曲霉毒素所污染。乳牛摄食受黄曲霉毒污染的饲料,牛奶中就含黄曲霉毒素,危害人类健康。黄曲霉毒素对     

鸡单端孢霉毒素中毒病的诊断

单端孢霉毒素 (单端孢霉烯族化合物包括T 2毒素 ) ,是由多种霉菌如镰刀菌、木霉、头孢霉、单端孢霉等多种霉菌产生的霉菌毒素。本病多发于猪 ,家禽次之 ,牛、羊等反刍动物较少发生。家禽中毒后 ,发生以口腔粘膜、神经和羽毛损伤为特征的疾病。本文通过流行病学调查、临床症状、病理变化观察及病原分离 ,确诊 70日龄鸡群暴发的以口腔粘膜损伤为特征的流行性疾病是单端孢霉毒素中毒病     

鹿霉玉米中毒的诊治报告

霉变玉米的主要成份是黄曲霉菌和赤霉菌,其毒性代谢产物是黄曲霉毒素和赤霉菌毒素。并且霉变玉米引起了许多家畜和家禽的中毒。现将一起鹿霉玉米中毒情况报告如下:     

A tremorgenic mycotoxicosis of cattle caused by maize sprouts infested with Aspergillus clavatus

An outbreak of disease affecting a herd of 16 dairy cattle which were fed mouldy, sprouted maize is described. Eight of the cattle were affected, 5 of which died. The clinical signs included muscular tremors, hypersensitivity, ataxia, anorexia and salivation. Aspergillus clavatus was the only fungus isolated from the sprouts. Clinical signs that were indistinguishable from those in the field outbreak were reproduced by dosing the mouldy maize sprouts to a steer and a sheep, and by dosing another sheep with maize inoculated with a pure culture of A. clavatus isolated from the mouldy maize on the farm. Light microscopical examination revealed neuronal degeneration and necrosis in the midbrain, medulla oblongata and spinal cord of all 3 of these animals. The disease is clinically and pathologically indistinguishable from the disease caused by the ingestion of sorghum beer residue, and in certain respects it is similar to toxicoses caused by the ingestion of wheat sprouts and malt sprouts infested with A. clavatus.     

霉玉米对小鼠体重和外周血淋巴细胞数量的影响

50只小鼠随机分为5组,每组10只,用于研究霉玉米对小鼠体重及外周血液淋巴细胞的影响。试验前将1组小鼠处死,采样作为对照,其余4组饲喂霉玉米饼,每周处死1组采样。结果表明,试验组小鼠的体重下降,但攻毒前后比较差异不显著(P>0.05);试验组小鼠的外周血中T淋巴细胞数量减少极显著(P<0.01)。表明霉玉米中毒影响小鼠的免疫功能,造成T、B淋巴细胞计数的改变。     

The occurrence of a toxigenic strain of Fusarium tricinctum in connection with disease in a dairy cow]

The fungus Fusarium tricinctum, producing T-2 toxin, was isolated from mouldy maize silage. T-2 toxin was identified by TLC and by a bioassay. Consumption of mouldy silage resulted in a disease in a dairy cow, which had to be killed. The patho-anatomical findings obtained in the slaughtered cow generally suggested trichothecene poisoning. It was derived from these findings that the disease was due to the presence of trichothecenes in the feed.     

AFLATOXIN CONTAMINATION OF AUSTRALIAN ANIMAL FEEDS AND SUSPECTED CASES OF MYCOTOXICOSIS

Aflatoxin B₁ was detected in 23 of 55 Australian feedstuffs known to be either water damaged or visibly mouldy. The highest contamination was 0.7 mg/kg of feed and the mean concentration 0.14 mg/kg. Of 36 feedstuffs purchased from local manufacturers, only a peanut meal contained aflatoxin B₁ (0.5 mg/kg).
Eleven feedstuffs were associated with field outbreaks of animal disease and 7 of these contained aflatoxin. However, the level of aflatoxin contamination was insufficient to account for the described disease symptoms.     

An Outbreak of Gangrenous Syndrome among Buffaloes and Cattle in West Bengal: Clinicopathological Studies

Gangrenous syndrome/Degnala disease was recorded in a large number of buffaloes and cattle in Murshidabad district of West Bengal, India. Fusarium spp. had been isolated from the mouldy paddy straw which were fed to the animals. There was a reduction in the incidence of the disease following withdrawal of the mouldy paddy straw. Histopathological examination showed necrosis and loss of architectural details in the skin.     

Effect of feeding sheep on naturally spoiled rice straw, clover hay and concentrate feed mixtures

The effects of feeding naturally contaminated feedstuffs to sheep were investigated through feeding of contaminated and uncontaminated clover hay, rice straw, and concentrate feed mixture were compared. The highest level of contamination with fungi was observed in the concentrate feed mixture followed by clover hay and rice straw. The most dominant mycotoxin in the contaminated feedstuffs was zearalenone. Contamination resulted in increases of crude protein, ash and silica in feedstuffs while both ether extract and crude fibre decreased. In vivo digestibility of different diet constituents in both contaminated and uncontaminated feedstuffs were determined using four mature Rahmani rams. Contamination resulted in significant increase in the digestibility of dry matter, crude fibre and energy. Contamination affected feed intake of the different feedstuffs particularly the concentrate feed mixture. A metabolism trial was also conducted to study the nitrogen and mineral balance. Retention of nitrogen and calcium was reduced when mouldy feeds were given. On the other hand, magnesium was relatively increased. Blood analysis for sheep at the end of the trials resulted in elevated values of inorganic phosphorus and phospholipid phosphorus and declined total nitrogen, calcium, cholesterol, calcium/phosphorus ratio and cholesterol/calcium ratio due to feeding on mouldy ration. Results of the urine analysis during the metabolism trials proved that mouldy ration increased the estimated values of the concentration of calcium, magnesium and vitamin C; whereas pH values, total nitrogen, ammonia nitrogen and inorganic phosphorus were declined during the feeding on the mouldy ration. Mouldy feeds tested, seemed to have toxic, nephritic and hepatic effect.     

家蚕血液超氧化物歧化酶活力及其影响因素

家蚕血液超氧化物歧化酶（SOD）随着蚕的发育而呈现有规律的动态变化：幼虫4龄期SOD活性高于5龄，同一龄中以龄初和龄末较高，而中期较低；化蛹后．SOD活性迅速增加，蛹中期活性达到最大值，随后迅速下降直至羽化；雌蚕的SOD活性均高于雄蚕，但蛹期SOD活性却以雄性较高；不同蚕品种间SOD活力有较大差异；SOD活力与饲料也有很大关系，人工饲料有蚕的活力显著高于桑叶育蚕；氟化物处理在初期引起SOD活性上升，但随后即下降并低于对照。研究认为，家蚕体内SOD活性与蚕的发育、变态及健康状况具有密切的关系。     

干肉制品中霉菌PCR鉴定方法的建立

为了早期预防传统牛肉干发生霉变,建立了牛肉干中真菌PCR的鉴定方法,在特异性和敏感性方面对所建立的PCR方法进行了验证。其中特异性试验以霉变的鲜牛肉、酵母菌、乳酸球菌、乳酸杆菌、大肠杆菌为材料进行验证;敏感性试验以霉变的鲜牛肉为材料,提取其DNA并将其稀释成不同的浓度进行PCR验证。结果显示：特异性试验中仅霉菌样品在约300 bp处出现特异性条带,而其他样品在该处无特异性条带出现,表明具有良好的特异性;敏感性试验中,霉菌DNA原液、10倍稀释、100倍稀释、1 000倍稀释时均出现了约300 bp的特异性条带,即霉菌DNA模板稀释度为1 000倍（2 ng/μL）时仍对引物有敏感性。该试验为市场传统牛肉干真菌PCR检测工作提供了依据。     

牙克石地区雏鸭霉高粱中毒的病因研究

1985年5月,内蒙古牙克石市某个体养鸭户饲养的5010只雏鸭在1个月内相继发病死亡.病鸭主要表现食欲减退,增重缓慢,拱背,腹泻,抽搐,卧地不起等.剖检,肝脏呈土黄色,心肌变性,胆囊胀满.通过流行病学调查、真菌分离与鉴定以及动物接种试验等,确认为霉高粱中毒,其致病真菌是扩展青霉(Penicillium expansum Tink)和鲜绿青霉(Peniciliumviridicatum Westling).     

国产赛福丁对绵羊的毒性及治疗绵羊痒螨病的效果

应用国产赛福丁对3组绵羊(每组3只)分别以10、20、40 mg/kg剂量进行了毒性试验。结果,10、20 mg/kg剂量的绵羊,药后临床未出现任何毒性反应;40 mg/kg剂量的绵羊,均于药后40～60 min出现了典型的有机磷中毒症状。全血胆碱酯酶对赛福丁非常敏感,但其抑制程度与中毒靠状的出现并无直接关系。中毒后血清GOT和GPT无变化。以50、100、200、250 ppm浓度的赛福丁溶液分别药浴患痒螨绵羊,均可迅速地治愈患羊,浴后24 h即可杀灭全部螨虫,24～72 h痒觉消失,2周后脱痂,长毛。近期疗效同于倍特和林丹.而远期疗效优于倍特和林丹。证明国产赛福丁是一种高效、低毒的杀螨剂。