单端孢霉烯族毒素的致病机理及防治措施研究进展

霉菌毒素是霉菌在生长繁殖过程中的次级代谢产物,种类繁多并表现出\"多菌产一毒,一菌产多毒\"的特点.动物一旦采食被霉菌毒素污染的饲料,将会由于摄入数量的不同对机体产生不同程度的伤害,统称为霉菌毒素中毒症.畜产品中霉菌毒素的累积和残留进入人体后对人类健康也会造成巨大的损害.单端孢霉烯族毒素是被世界卫生组织认定的危险物,且其造...     

单端孢霉烯族毒素生物脱毒技术研究进展

单端孢霉烯族毒素在粮食和饲料中污染严重,主要是T-2毒素和脱氧雪腐镰刀烯醇(DON)等,其毒性作用强,对人和动物产生严重危害.因此,单端孢霉烯族毒素的脱毒方式逐渐成为研究热点,尤其是生物脱毒.很多微生物被证实能够降解霉菌毒素,包括细菌、真菌和酵母菌,可将毒素降解成低毒或无毒的产物.论文以生物脱毒为出发点,从细菌、真菌和...     

气相色谱-质谱检测饲料中B类单端孢霉烯族毒素

建立了气相色谱-质谱联用同时测定饲料中脱氧雪腐镰刀菌烯醇和雪腐镰刀菌烯醇的方法。饲料样品中毒素提取液经Mycosep227多功能净化柱净化后,利用硅烷化试剂TBT(三甲基硅烷咪唑:双三甲基硅基乙酰胺:三甲基氯硅烷=3:3:2,V/V/V,与B类单端孢霉烯族毒素进行衍生化反应。HP-5MS毛细管柱作为色谱柱分离毒素,质谱进行检测。外标法定量。脱氧雪腐镰刀菌烯醇和雪腐镰刀菌烯醇标准溶液提取离子峰面积与标品浓度分别在10～1300ng/ml、8～1300ng/ml内呈良好的线性关系,饲料样品中两种毒素不同加入量的回收率分别在81.7%～92.6%、78.2%～87.8%之间,最低检出限为9ng/g、7ng/g,批间与批内的相对标准偏差均小于10%。该方法检测灵敏度高且具有良好的重现性。     

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     

脱氧雪腐镰刀菌烯醇的毒性、作用机制以及对动物健康的危害(一)

脱氧雪腐镰刀菌烯醇(DON),通常称作"呕吐毒素",是最常被检测到的一种单端孢霉烯族毒素,通常以mg/kg(饲料,体重等)计。所有动物都对DON很敏感,由于DON在不同动物品种体内的吸收、代谢、分布和排出的方式不同,可导致对毒性敏感性的差异,其毒性大小顺序为:猪>小鼠>大鼠>家禽≈反刍动物。谷物籽实常有少量谷粒被3-乙酰基DON和15-乙酰基DON污染,毒素水平较低(等于或低于小鼠半数致死剂量)时不会对动物造成严重的危害。急性口服高剂量DON(≥27mg/kg体重)摄入引起试验动物死亡或者明显的组织损害。然而,对DON最敏感的猪,相对较低的剂量(≥50g/kg体重)就可以引起呕吐,其表现与人类食物中毒类似,原发性症状为恶心、腹泻和呕吐等。试验动物长时间饲喂DON污染的饲料,表现增重迟缓、食欲减退、养分利用率降低和免疫功能的改变,并且这种影响随种属差异变化较为明显。     

霉菌毒素介导的氧化应激研究进展北大核心CSCD

霉菌毒素是霉菌生长产生的次级代谢物,其高毒性和强致癌性严重威胁动物生产性能和人类健康,给畜牧业和食品工业带来巨大经济损失,因此,研究霉菌毒素的毒性机制具有重要的意义。霉菌毒素引起机体氧化应激,继而引发细胞毒性作用,如细胞凋亡、DNA损伤等。本文综述了主要的几种霉菌毒素吸收与代谢,重点阐述了由氧化应激介导的毒性作用,以期对霉菌毒素毒性机制有更加全面认识,为从缓解氧化应激的角度解决畜禽生产中霉菌毒素问题提供理论依据。     

猪霉菌毒素中毒的防治措施

霉菌毒素中毒症是指与污染了霉菌毒素的食物或饲料接触而引发的疾病。产毒霉菌有数百种,主要的霉菌毒素有黄曲霉毒素、玉米赤霉烯酮、单端孢霉烯族毒素、烟曲霉毒素、赫曲毒素和麦角生物碱六大类。作物上的霉菌可在田间及在加工和贮存期间均能产生霉菌毒素。通常情况下,人或动物是通过食用受霉菌毒素污染的食品或饲料而发生中毒的。霉菌毒素在动物体内可产生多种生理作用：肝毒、肾毒、对中枢神经系统的作用以及类似雌激素效应等。     

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。     

Analysis of Canadian and Irish forage,oats and commercially available equine concentrate feed for pathogenic fungi and mycotoxins

Respiratory infections, recurrent airway obstruction (RAO) and exercise induced pulmonary haemorrhage (EIPH) are major causes of poor performance in horses. Fungi and mycotoxins are now recognised as a major cause of these conditions. The most notable fungi are Aspergillus and Fusarium. Fungal spores can originate from forage, bedding and feed and, in turn, these fungal spores can produce a series of mycotoxins as secondary metabolites.This study set out to ascertain the degree of fungal and mycotoxin contamination in feed and fodder used in Irish racing yards over a one-year period. Weather conditions in forage producing areas were sampled by Met Eireann and the Canadian Meteorological Service.Fifty per cent of Irish hay, 37% of haylage and 13% of Canadian hay contained pathogenic fungi. Of the mycotoxins, T2 and zearalenone were most prominent. Twenty-one per cent of Irish hay and 16% of pelleted feed contained zearalenone. Forty per cent of oats and 54% of pelleted feed contained T2 toxins.     

青贮饲料中霉菌毒素的产生及对反刍动物健康的影响

青贮饲料营养丰富,适口性好,易消化且能够长期保存,是反刍动物日粮中最重要的组成部分之一。青贮饲料在收获、发酵以及取用过程中都有可能受到霉菌毒素的污染,其中主要包括黄曲霉毒素B1、玉米赤霉烯酮、脱氧雪腐镰刀菌烯醇、赭曲霉毒素A、伏马菌素以及其他真菌次级代谢产物。反刍动物摄取发霉青贮饲料,会对其生产性能及健康产生严重影响。加强青贮饲料收获前、青贮过程及饲喂期的管理,对于减少反刍动物饲料中的霉菌毒素污染至关重要。此外,某些霉菌抑制剂或微生物接种剂也可降低毒素的污染水平。本文主要就青贮饲料生产过程中出现的各种霉菌、霉菌毒素以及其对反刍动物健康的影响进行了综述,旨在为控制青贮饲料制作和饲喂过程中霉菌毒素的污染,降低经济损失提供参考。     

棘豆属植物的危害性及其控制对策初探

棘豆属植物对草地畜牧业的危害性主要表现在：与优良牧草竞争水肥、光照及空间,使草地植物学成分简化,生物多样性减少,抗逆性下降,草地退化加速,使用年限缩短,生产率和利用率降低。同时引起家畜中毒、繁殖性能减弱及育种改良难度增大。认为目前棘豆控制应从草地农业生态系统的整体出发,以生态学理论为指导,生态工程控制为基础,生物控制为中心,物理防治、科学管理及政策引导为辅助和补充手段,兼顾开发利用,化学防治为应急措施的综合控制体系。     

乳酸菌清除霉菌毒素作用及其机制

霉菌毒素广泛存在于食品和饲料当中,严重地危害人类和动物的健康。如何有效清除霉菌毒素一直是重要的研究课题。乳酸菌具有多种生物学功能,近年来研究表明,乳酸菌具有清除霉菌毒素能力。为了更好地理解乳酸菌清除霉菌毒素的作用,文章就近年来乳酸菌对霉菌毒素的清除机制加以综述。     

肉鸡沙门氏菌病的现状和对策

１沙门氏菌病的病性及其重要性沙门氏菌，特别是肠炎沙门氏菌（SE）和鼠伤寒沙门氏菌（ST）是人类的一种食源性中毒性疾病的病原，其公共卫生意义十分重大。近年来，SE和ST从禽肉、禽蛋中的检出率不断上升，欧美各国及南非、南韩政府卫生检疫部门越来越重视这一问题，已成为世界禽类产品贸易中的瓶颈之一。１９９８年５月，由于鸡肉沙门氏菌问题，南非政府吊销了中国六家肉鸡企业的出口许可证，使本来已经举步维艰的禽肉出口雪上加霜。近年来，因沙门氏菌问题被迫退货的事例，仍时有发生。不久，在入世开关的形势下，沙门氏菌问题必将愈…     

Feed preference and feeding behaviours in grower broilers fed diets containing wheat naturally contaminated with fusarium mycotoxins

1. Two trials were conducted to determine the effect of feeding diets contaminated with fusarium mycotoxins (primarily deoxynivalenol (DON)) on broiler chicken feed preference, feeding behaviour and growth performance.

2. A total of 120 male Ross 308 chicks (4 birds/cage, 30 cages) were fed a common corn-based starter diet from 1 to 20 d of age. At 21 d, 15 cages were randomly assigned to the feed preference trial or a feeding behaviour trial. Three wheat-based experimental diets (0.14, 2.27 and 5.84 mg/kg DON) were prepared with a clean wheat and a naturally contaminated wheat. Broilers were ad libitum fed the experimental diets during 21–27 d.

3. In the preference trial, each cage’s feeder was split into two equal-sized compartments so birds were provided a choice of two diets (control vs. low, control vs. high and low vs. high DON). In the feeding behaviour trial, diets were randomly assigned to 15 cages (5 cages/diet). Feeding and drinking behaviour was recorded for 1 h before and after the dark period and 1-h period at 9 h after the light was turned on (middle of day). Growth performance was assessed at 27 d.

4. In the preference trial, broilers preferred the control diet over low (93.0 vs. 66.1 g/d, P < 0.01) and high (104.4 vs. 50.4 g/d, P < 0.01) DON diets. At all three timepoints, where behaviour was recorded, birds offered the DON diets spent more time at the feeder compared to birds provided control diets (P < 0.05). Control birds had lower feed to gain ratio (1.65) than birds fed low (1.82) and high (1.94) DON diets (P < 0.01).

5. It is clear that broilers are sensitive to the presence of fusarium mycotoxins and that moderate levels of DON negatively affect feed preference and growth performance when fed during the grower period.     

The occurrence of Fusarium varieties and their mycotoxins in silo corn. 2. The formation of zearalenone in the field by artificial infection of silo corn with Fusarium culmorum (W. G. Smith) Sacc

The formation of zearalenone in a maize plot artificially infected with Fusarium culmorum was studied. The zearalenone concentration steeply increased only in the 8th week after inoculation and reached a maximum value of ca. 7 ppm, whereas zearalenone could not be detected in the control variants. The crude nutrient and dry matter content was not significantly influenced by the fungal infection. The infected crop showed average ear dry weights distinctly lower than that of the control variants (P less than or equal to 0.001). Apart from zearalenone, the mycotoxin deoxynivalenol was qualitatively detected in the infected maize. The toxicological relevance of the ascertained zearalenone content with regard to the health of dairy cattle and pigs was discussed.     

Studies on the application of enzyme immunoassays for the Fusarium mycotoxins deoxynivalenol, 3-acetyldeoxynivalenol, and zearalenone.

Polyclonal antisera against zearalenone (ZEA) were produced in rabbits after immunization with ZEA-oxime coupled to human serum albumin. Using these antibodies and a ZEA-oxime-horseradish peroxidase conjugate in a competitive direct enzyme immunoassay (EIA), the detection limit for ZEA was 70 pg/ml. The relative cross-reactivities of the assay with ZEA, alpha-zearalenol, beta-zearalenol, zearalanone, alpha-zearalanol, and beta-zearalanol, respectively, were 100%, 37.3%, 7.2%, 59.2%, 5.3%, and 3.9%, respectively. This EIA and two EIAs for deoxynivalenol (DON) and 3-acetyldeoxynivalenol(3-AcDON) (Usleber et al., 1991) were used to analyze wheat samples. The limits of determination for DON, 3-AcDON, and ZEA in wheat were 200 ppb, 50 ppb, and 20 ppb, respectively. The analysis of reference materials (wheat flour) containing DON by EIA showed good agreement with the nominal values. The EIA for ZEA was in addition used to analyze biological fluids, obtained during a feeding trial. Two lactating cows were administered 25 mg and 100 mg ZEA per day, respectively, over a period of 6 days. Serum, milk, urine, and feces were assayed in the ZEA-EIA with and without sample treatment with beta-glucuronidase prior to the analysis. Maximum toxin levels (ZEA-equivalents) found in milk were 0.4 and 1.2 ppb (glucuronides). The toxin concentration in milk decreased rapidly after the last toxin administration. In the urine, maximum levels of toxin-glucuronide conjugates were 23 ppb and 24 ppb, respectively. The serum toxin levels corresponded to those found in milk. In the feces, mean values were 150 ppb and 500 ppb, respectively, no conjugated toxins were found in feces.     

非洲猪瘟的研究进展及防控措施

非洲猪瘟是一种致死率极高的猪烈性传染病,文中阐述该病病毒特性、临床症状、病理变化等特点,结合欧洲对该病的防控手段,提出对非洲猪瘟的防控策略,一方面严防严控该病进入国内,另一方面对疫病暴发要提前准备,迅速控制。     

霉菌毒素分解酶枯草杆菌制剂对日粮含AFB1的艾维茵肉鸡的解毒效果研究

为研究在含有微量黄曲霉毒素B1 (AFB1)日粮中添加霉菌毒素分解酶枯草杆菌制剂对肉鸡生长性能、免疫器官指数和抗氧化能力的影响,本研究将120羽7日龄艾维茵肉鸡随机分成4组,每组3个重复。A组饲喂基础日粮,B、C、D组在基础日粮中分别添加50μg/kg AFB1、50μg/kg AFB1+0.1%枯草芽孢杆菌Pab02制剂和50μg/kg AFB1+0.1%霉菌毒素分解酶枯草杆菌制剂,饲喂28 d后测定肉鸡的生长性能、免疫器官指数、抗氧化能力及AFB1在肝脏和肌肉的残留量。结果显示:试验期间,除B组鸡出现精神沉郁和6.67%死亡率外,其余3组鸡均未出现病理症状和死亡现象;净增重D>A>C>B组(p>0.05),料重比B>C>D>A组(p>0.05);脾脏指数A>D>C>B组,并且A、D、C组极显著高于B组(p<0.01);B组血清和肝脏中的超氧化物歧化酶(SOD)活性和总抗氧化能力(T-AOC)显著或极显著低于A、D组(p<0.05或p<0.01),丙二醛(MDA)含量极显著高于A、C、D组(p<0.01);各组肉鸡肝脏和肌肉中黄曲霉毒素的残留量A相似文献