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1.
赭曲霉毒素A(Ochratoxin A,OTA)是一类免疫抑制类真菌毒素,主要由曲霉属和青霉属等产毒真菌产生。OTA作为食品和饲料原料的一种常见污染物,在各种粮食作物及其副产品中广泛存在,可对肾脏、肝脏、免疫器官、生殖系统等造成损伤,对动物和人类健康造成严重威胁,给畜牧养殖业带来巨大的经济损失。广泛存在的OTA可诱发机体产生肾毒性、肝毒性、免疫毒性、癌变畸变等,但其具体致毒机制目前尚不完全清楚。本文就国内外OTA研究情况进行归纳总结,为深入研究OTA对动物机能的毒性机制提供依据,为合理有效防控OTA损伤及保障畜禽健康养殖提供参考。  相似文献   

2.
赭曲霉毒素A(OTA)是一类免疫抑制类真菌毒素,主要由曲霉属和青霉属等产毒真菌产生。OTA作为食品和饲料原料的一种常见污染物,在各种粮食作物及其副产品中广泛存在,其自身的免疫毒性效应对动物生产和人类健康造成极大的危害,由此引起人们的高度关注。赭曲霉毒素在饲料中广泛存在,饲料中的OTA对动物危害严重,诱发机体产生严重的免疫毒性,但其具体机制目前尚未完全清楚。论文就OTA对动物器官免疫、非特异性免疫、特异性免疫的研究现状进行综述,为深入研究OTA对动物免疫机能的损害机制提供参考依据。  相似文献   

3.
赭曲霉素A(OTA)是普遍存在各个领域的一种重要食品污染物。具有强烈肾毒性、肝毒性、免疫毒性、并具有致畸、致癌、致突变性,曾一度被认为是巴尔干肾病的主要病原。OTA在饲料中、动物性产品中存在和蓄积很普遍,而且在人乳中也检测到有OTA的存在,这对人类健康具有很大的威胁性。  相似文献   

4.
赭曲霉毒素A是由一分子异香豆素与一分子苯丙氨酸通过肽键连接而成的真菌毒素,常会对谷物和饲料造成污染,是一种较强的致癌因子、致畸因子和代谢毒素,对人和动物具有肾毒性、肝毒性和免疫毒性。  相似文献   

5.
赭曲霉素A(OTA)是曲霉属和青霉属一些产毒菌株次级代谢产物,是一种重要食品污染物.具有强烈肾毒性、神经毒性、免疫毒性、并具有致癌、致畸、致突变性,曾一度被认为是巴尔干肾病的主要病原.OTA在饲料中的含量很高,而且污染极其广泛. 几乎可污染玉米、小麦等所有的谷物,而且能够在动物性产品中蓄积,尤其在猪的肾脏、肝脏、肌肉、血液、以及奶和奶制品等中常被检出,在人乳中也检测到有OTA的存在,这对人类健康具有很大的潜在威胁.有研究表明,OTA对动物的毒性具有阈值机制,低剂量的OTA对机体是无害的,是否正确还需要进一步研究.  相似文献   

6.
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。  相似文献   

7.
赭曲霉毒素A(OTA)是赭曲霉毒素中毒性最强,分布最广且危害最大的真菌毒素.是曲霉属和青霉属等产毒菌株产生的一组结构类似的有毒代谢产物,广泛存在于各种食品、饲料及其他农副产品中,导致大量的饲料原料受到污染,对畜禽养殖构成威胁,甚至引起畜禽死亡.如果用赭曲霉毒素A含量较高的玉米饲喂鸡只一段时间后,往往会引起鸡肾脏肿胀、花斑肾,与肾病变型传染性支气管炎的变化相似而易误诊,造成鸡只的大量死亡,给养殖户带来较大的经济损失.宜宾某养殖户乌骨鸡发生赭曲霉毒素A中毒病例介绍如下.  相似文献   

8.
赭曲霉毒素A(OTA)是一种对人和动物具有广泛毒性的霉菌毒素,为建立OTA在食品和饲料中的快速检测方法,采用活性酯法(NHS)将OTA与牛血清白蛋白(BSA)、鸡卵清白蛋白(OVA)偶联,分别制备了免疫原OTA-BSA和包被原OTA-OVA。紫外扫描和SDS-PAGE鉴定表明,OTA与BSA和OTA与OVA偶联成功,偶联物OTA-BSA和OTA-OVA的偶联比分别为7∶1和4.5∶1。用免疫原OTABSA免疫Balb/c小鼠,制备多克隆抗体,用OTA-OVA包被ELISA板进行检测,小鼠血清中抗OTA的抗体效价最高可达1∶51 200。表明制备的免疫原OTA-BSA具有良好的免疫原性,为OTA单克隆抗体的制备奠定了基础。  相似文献   

9.
赭曲霉(Ochraceus)为重要的贮藏菌,寄生在食品、粮食和饲料中,能产赭曲霉毒素A、B、C等有毒代谢产物,这种毒素主要侵害肝、肾,是一种强烈的肝脏毒和肾脏毒。当人和畜禽持续摄入被该毒素污染的食物及饲料时,不仅会出现急性症状和死亡,也可形成严重的慢性病变,可导致受试动物肾萎缩,胎儿畸形,流产,肝、肾癌变。  相似文献   

10.
正近日,中国农业科学院农产品加工研究所刘阳团队发现一个负责赭曲霉毒素合成的基因簇,阐明了赭曲霉毒素合成步骤及两个关键调控基因。该研究对预防和控制赭曲霉毒素污染具有非常重要的意义。相关研究成果作为亮点文章在线发表在《应用与环境微生物(Applied and Environmental Microbiology)》上。赭曲霉毒素A(OTA)广泛存在谷物、咖啡、葡萄、酒类、奶酪、肉制品中,具有肾毒性、致癌性、致畸性及免  相似文献   

11.
黄曲霉毒素主要是由黄曲真菌和寄生曲真菌产生的一类高毒性次级真菌代谢物质,世界范围内大部分的粮食和动物饲料受到黄曲霉毒素的污染,对动物健康与畜禽养殖业可持续发展构成严重威胁。黄曲霉毒素B1(aflatoxin B1,AFB1)是众多霉菌毒素中常见且毒性较强的一种,过量摄入AFB1具有致癌、致畸、免疫抑制等毒性效应。大量研究证实AFB1可对肉鸡的生长、免疫功能、器官发育等方面造成严重影响,威胁家禽业的健康发展。结合国内外研究报道,对黄曲霉毒素的性质、毒性进行概述,从肠道功能障碍、免疫抑制、器官损伤和遗传毒性四个方面阐述AFB1对肉鸡毒性作用的研究进展,以期为进一步阐明黄曲霉毒素对肉鸡毒性作用的分子机制,同时为减轻黄曲霉毒素对肉鸡养殖造成的危害提供参考。  相似文献   

12.
1. The effect of dietary formic acid on performance, digestibility, intestinal histomorphology and plasma metabolite levels of broiler chickens was studied. 2. An experiment with 120 Ross male broiler chickens was conducted from 1 to 42 d of age at the laboratory. There were 4 treatment groups: control (C), 10 mg/kg feed avilamycin (AV) and formic acid at two concentrations, 5 and 10 g/kg feed (FA5 and FA10, respectively). 3. No differences in weight gain, feed intake or feed conversion ratio were observed in male broiler chickens fed on the different diets. 4. An effect of the additives on ileal dry matter (DM) digestibility at 42 d of age was detected with the finisher diets; AV and 10 g/kg of feed formic acid slightly improved ileal DM digestibility compared to the other treatment groups. 5. Jejunum pH was not affected when 5 or 10 g/kg formic acid was added, and the results do not clearly show a positive effect of formic acid on the intestinal histomorphology. 6. No differences were noticed for blood metabolites in the different diets, and the levels of calcium and phosphorus in the plasma were not altered by formic acid addition. 7. In conclusion, when using broiler chickens under conditions of good hygiene, dietary formic acid did not have a clear positive effect on performance, intestinal histomorphology or plasma metabolite levels; however, there was a slight positive effect on the ileal digestibility of nutrients.  相似文献   

13.
本试验旨在研究霉变饲料和/或添加复方霉菌毒素吸附剂对肉鸡人工感染发生的影响。选取140羽1日龄健康的AA肉鸡随机分成7个组.每组4个重复。第1组为空白对照组,饲喂基础日粮;第2组饲喂霉变饲料;第3~7组以混合感染病鸡病变组织匀浆饮水制作人工感染疾病模型;第3~7组分别饲喂基础日粮、霉变饲料、霉变饲料+复方霉菌毒素吸附剂、霉变饲料+复方霉菌毒素吸附剂+抗氧化剂、霉变饲料+复方霉菌毒素吸附剂+抗氧化剂+中药增免剂。试验期35d。结果发现,肉鸡摄入霉变饲料与摄入正常饲料相比,提高肉鸡料重比和死淘率,显著降低肉鸡增重、胸腺指数、法氏囊指数,显著降低血清IBDV、H9N1v和NDV抗体水平(P〈0.05)。给人工感染肉鸡饲喂霉变饲料与饲喂正常饲料相比.显著提高料重比和死淘率,显著降低肉鸡增重、胸腺指数和脾脏指数,显著降低血清IFN-1、IL-2、IL-4和IL-12含量以及LTR,显著降低血清IBDV、H9N1V和NDV抗体水平(P〈0.05)。霉变饲料中添加复方霉菌毒素吸附剂能显著提高混合感染肉鸡增重,并降低料重比和死淘率(P〈0.05),显著提高胸腺指数、法氏囊指数(P〈0.05),显著提高血清IBDV、H9N1V和NDV抗体水平(P〈0.05)。可见,霉变饲料可导致肉鸡免疫功能抑制,加重肉鸡混合感染病情;复方霉菌毒素吸附剂能有效缓解霉变饲料对人工感染肉鸡生产性能、免疫功能和病情的不利影响,抗氧化剂和免疫功能增强剂可减轻霉变饲料的毒性作用。  相似文献   

14.
为更好地了解国内外黄羽肉鸡饲料营养的最新研究进展,经查阅并总结了2017-2018年关于黄羽肉鸡饲料营养的国内外文献,旨在为黄羽肉鸡安全、高效养殖提供技术参考。作者主要从黄羽肉鸡营养需要量、饲料添加剂应用技术研究、非常规饲料原料安全高效利用技术研究、饲料原料营养价值评定等几方面进行综述,并指出在黄羽肉鸡饲料营养的应用及研究中应关注以下内容:明确饲料原料中矿物元素、维生素的含量,减少维生素和矿物元素的资源浪费;中草药具有多糖、生物碱、皂甙和有机酸等多种活性成分,建议使用时应合理配伍制成多功能中药添加剂,使其对黄羽肉鸡生产性能、免疫功能等方面都有提高改善作用;益生菌添加剂是一种对黄羽肉鸡养殖有效、绿色环保的添加剂,其中芽孢杆菌和酵母效果较好,两种益生菌组合使用其效果更佳;改进植物性饲料原料的生产工艺以提高其利用率;开发新型的动物性蛋白原料,如蝇蛆和黑水虻等昆虫类动物性蛋白具有安全、绿色环保等优势,是新型动物性蛋白原料的优选。总之,中国的黄羽肉鸡高效养殖技术仍有待进一步的提高,建议完善黄羽肉鸡、种鸡饲养标准,开展更广泛的黄羽肉鸡饲料资源安全高效利用技术研究以及黄羽肉种鸡母体营养对后代肉鸡的影响及其机制。  相似文献   

15.
(1) The objective of this study was to determine whether the dietary inclusion of Trichosporon mycotoxinivorans (TRM) could suppress the detrimental effects of ochratoxin A (OTA) on the immune system of broiler chicks. (2) Six experimental treatments were tested in 300 1-d-old broiler chicks. Treatments included addition to a standard broiler ration of neither OTA nor TRM (Diet 1), OTA alone (500 microg/kg), OTA plus TRM at three inclusion rates (10(4) CFU/g of feed, 10(5) CFU/g, 10(6) CFU/g) and TRM alone at 10(5) CFU/g of feed. The ration was fed to chicks for 42 d. (3) Blood samples were collected at d 10, 20, 30 and 40 and macrophages and heterophils were isolated. The following variables were determined in macrophages and heterophils activated by phorbol myristate acetate (65 microM): cell viability, total cell-associated urokinase-plasminogen activator (u-PA), membrane-bound u-PA, free u-PA binding sites and superoxide production. (4) There was a decrease in the viability of macrophages and heterophils from chicks receiving OTA-contaminated feed compared to the viability of cells from control birds at d 40. Dietary TRM completely blocked the effect of OTA on cell viability; all three inclusion rates were equally effective. There was a decrease in total cell-associated and membrane-bound u-PA in macrophages and heterophils of chicks receiving OTA-contaminated feed compared to the corresponding values in control birds for heterophils at d 30 and 40 and for the macrophages at d 40. (5) Similarly, dietary TRM abolished the effect of OTA on total cell-associated and membrane-bound u-PA activity. All three inclusion rates of yeast were equally effective. Heterophils, but not macrophages, isolated from chicks receiving OTA-contaminated diet produced less superoxide anion compared to all other diet groups at d 30 and 40. (6) The immune system is a primary target of OTA toxicity in broilers: several functional properties of macrophages and heterophils were depressed in chicks fed OTA-contaminated feed. There was a delay of 30d before the immunosuppressive effect became apparent. The dietary inclusion of TRM completely blocked the detrimental effects of OTA on several immune properties in broilers.  相似文献   

16.
Mycotoxins are secondary fungal metabolites, whose presence in feed- and foodstuffs is unavoidable. Ochratoxin A (OTA) is one of the known mycotoxins with greatest public health and agro-economic significance. Several toxic effects have been ascribed following exposure, namely nephrotoxicity, as well negative impacts in the performance of farm animals, resulting in major economic implications. Of no less importance for the route of human exposure that can also embody the carry-over of OTA from feed into animal-derived products is also a concern. For all these reasons the present article updates the worldwide occurrence of OTA in different raw ingredients and finished feed destined to food-producing animals. After that a brief characterization of specie susceptibility and the major rationales is made. An historical overview of field outbreaks linked to OTA exposure in farm animals, concerning the implicated feeds, contamination levels and major clinical and productivity effects is presented. Finally a review of the major animal health and performance potential impacts of animals being reared on contaminated feed is made allied to a perspective regarding its co-occurrence with other mycotoxins, and simultaneous parasitic and bacterial infections. Ultimately, this article aims to be instructive and draw attention to a mycotoxin so often neglected and elapsed from the list of differential diagnosis in farm practice. For the unpredictability and unavoidability of occurrence, OTA will definitely be an enduring problem in animal production.  相似文献   

17.
Background: Intestinal microbiota plays a key role in nutrient digestion and utilization with a profound impact on feed efficiency of livestock animals. However, the intestinal microbes that are critically involved in feed efficiency remain elusive.Methods: To identify intestinal bacteria associated with residual feed intake(RFI) in chickens, male Cobb broiler chicks were individually housed from day 14 to day 35. Individual RFI values were calculated for 56 chickens.Luminal contents were collected from the ileum, cecum, and cloaca of each animal on day 35. Bacterial DNA was isolated and subjected to 16 S rRNA gene sequencing. Intestinal microbiota was classified to the feature level using Deblur and QIIME 2. High and low RFI groups were formed by selecting 15 and 17 chickens with the most extreme RFI values for subsequent LEfSe comparison of the difference in the microbiota. Spearman correlation analysis was further performed to identify correlations between the intestinal microbiota composition and RFI.Results: No significant difference in evenness, richness, and overall diversity of the microbiota in the ileum, cecum,or cloaca was observed between high and low RFI chickens. However, LEfSe analysis revealed a number of bacterial features being differentially enriched in either high or low RFI chickens. Spearman correlation analysis further identified many differentially enriched bacterial features to be significantly correlated with RFI(P 0.05). Importantly,not all short-chain fatty acid(SCFA) producers showed a positive association with RFI. While two novel members of Oscillibacter and Butyricicoccus were more abundant in low-RFI, high-efficiency chickens, several other SCFA producers such as Subdoligranulum variabile and two related Peptostreptococcaceae members were negatively associated with feed efficiency. Moreover, a few closely-related Lachnospiraceae family members showed a positive correlation with feed efficiency, while others of the same family displayed an opposite relationship.Conclusions: Our results highlight the complexity of the intestinal microbiota and a need to differentiate the bacteria to the species, subspecies, and even strain levels in order to reveal their true association with feed efficiency. Identification of RFI-associated bacteria provides important leads to manipulate the intestinal microbiota for improving production efficiency, profitability, and sustainability of poultry production.  相似文献   

18.
本试验旨在探讨注射地塞米松(DEX)模拟应激状态下,应激和饲粮能量水平对肉仔鸡能量采食的影响。选取体重相近的180只23日龄的雄性爱拔益加(AA)肉鸡随机分成6组,每组3个重复,每个重复10只鸡。试验采用2×3析因设计,因素为DEX[处理(注射DEX2 mg/kg)、未处理(注射等剂量生理盐水)]和饲粮能量水平[高能(HE)、低能(LE)以及高能、低能自由采食(H-LE)]。预试期5 d,正试期7 d。结果表明:1)DEX处理极显著降低了肉仔鸡的采食量和体增重(P<0.01),极显著提高了耗料增重比、耗能增重比、腹脂率以及血浆葡萄糖、甘油三酯和尿酸的浓度(P<0.01),显著提高了肠道指数(P<0.05)。2)采用LE饲粮体增重(P<0.05)、腹脂率(P<0.01)显著低于其他2种饲粮,耗料增重比显著低于HE饲粮(P<0.05);采用HE饲粮耗能增重比极显著高于其他2种饲粮(P<0.01);采用H-LE饲粮神经肽Y(NPY)基因表达量显著高于LE饲粮(P<0.05)。3)DEX、饲粮能量水平对耗料增重比(P<0.05)和耗能增重比(P<0.01)的影响存在显著的互作效应。结果提示,DEX应激可使肉仔鸡血浆中葡萄糖、尿酸和甘油三酯的浓度升高;DEX应激和HE饲粮均能增加脂肪在腹部沉积,提高耗料增重比和耗能增重比;H-LE饲粮能上调肉仔鸡下丘脑NPY基因表达。  相似文献   

19.
Clostridium botulinum type C toxicosis was diagnosed by the mouse inoculation test in two outbreaks of botulism in commercial broiler and roaster chickens. One case involved 7-wk-old commercial roaster chickens, and the other involved 15-day-old commercial broiler chickens. A definitive point source for preformed C. botulinum exotoxin was not identified in either case investigation. Elevated iron concentrations in the drinking water and/or feed may have presented a significant risk factor that may have resulted in intestinal proliferation of C. botulinum and subsequent botulism.  相似文献   

20.
A large S. infantis infection epidemic in broiler chickens was studied during a period of one year. The outbreak affected three broiler producing companies in Finland. The infection spread to breeding farms according to available data during the summer of 1975. The epidemic still prevailed at the end of the studies on the farms of certain companies.The origin of the infection and the means of its spreading could not be ascertained. Some epidemiological evidence suggesting that a hatchery might have spread the infection was found. Contaminated feed may also have been involved, although the findings do not support feed as the principal vehicle in the epidemic. A complex pattern of transmission is most probable.A microbiological preventive method based on the feeding of a culture of intestinal flora of adult chickens to newly hatched broiler chickens was used on many farms in the study. The feeding of the culture lowered the proportion of infected flocks on the farms and significantly lowered the number of infected birds in those flocks, where the prevention was not complete. kw|Keywords|k]Salmonella infantis; k]infection; k]epidemic; k]broiler chicken  相似文献   

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