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1.
In order to detect the presence of aflatoxin B1 (AFB1), the use of the enzyme-linked immunosorbent assay (ELISA) and recovery test was evaluated. The detection limit of ELISA for AFB1 was 1 pg/assay and the recovery from maize spiked with AFB1 exceeded 80%. AFB1 was detected by ELISA in seven out of twelve samples of imported food products including peanut, almond, red pepper, cocoa bean, black pepper, buckwheat, walnut, adlay, soybean, popcorn, and pistachio nut, and by high performance liquid chromatography (HPLC) in four of the samples. However, the content of AFB1 in these samples was less than 10 ng/g of the minimum value authorized by the Japanese sanitation law. These results demonstrate that ELISA is more sensitive than HPLC and imported food products are broadly contaminated with AFB1.  相似文献   

2.
Aflatoxins, a family of closely related, biologically active mycotoxins, have been known as a prominent cause of animal disease for 30 yr. The toxins occur naturally on several key animal feeds, including corn, cottonseed, and peanuts. Occurrence of aflatoxin on some field crops tends to spike in years when drought and insect damage facilitate invasion by the causative organisms, Aspergillus flavus and A. parasiticus, which abound in the crop's environment. Acute aflatoxicosis causes a distinct overt clinical disease marked by hepatitis, icterus, hemorrhage, and death. More chronic aflatoxin poisoning produces very protean signs that may not be clinically obvious; reduced rate of gain in young animals is a sensitive clinical register of chronic aflatoxicosis. The immune system is also sensitive to aflatoxin, and suppression of cell-mediated immune responsiveness, reduced phagocytosis, and depressed complement and interferon production are produced. Acquired immunity from vaccination programs may be substantially suppressed in some disease models. In such cases the signs of disease observed are those of the infectious process rather than those of the aflatoxin that predisposed the animal to infection. Mixtures of aflatoxin with other mycotoxins can result in greatly augmented biological responses in terms of rate of gain, lethality, and immune reactivity. Because of its great biological activity, its wide-spread potential presence in areas where critical feed crops are grown, and its propensity to spike in problem years, aflatoxin promises to be a continuing problem in animal production.  相似文献   

3.
Effects of aflatoxin on bovine rumen motility were determined by radiotelemetric techniques. Aflatoxin altered amplitude and/or frequency of rumen contractions in steers given dosages of 0.2, 0.4, 0.6, or 0.8 mg of aflatoxin/kg of body weight. Effects of aflatoxin on rumen motility were dose dependent. An increase in elimination time of aflatoxin from rumen contents was observed in steers given the aflatoxin dosages of 0.4 to 0.8 mg/kg. The increase in elimination time of this toxin facilitates diagnostic capabilities for detecting bovine aflatoxicosis by obtaining rumen contents for analysis for aflatoxin. Aflatoxin M1 was detected in rumen contents from steers at 2 hours after aflatoxin was administered. Thus, intraruminal metabolism of aflatoxin B1 to M1 may occur.  相似文献   

4.
During 1983, 1984, and 1985, aflatoxicosis was diagnosed in 8 Iowa swine herds after the herds were fed corn from the 1983 corn crop. As a result of the diagnosis, the associated environmental conditions, clinical signs of aflatoxicosis, macroscopic and microscopic lesions, aflatoxin concentrations detected in feeds, and management of affected swine were reviewed. Concentrations of aflatoxin in shelled corn and complete feed were as high as 2,020 ng and 1,200 ng of aflatoxin (B1 and B2)/g of feed, respectively. Clinical signs of aflatoxicosis included decreased feed consumption and weight loss. Some pigs died acutely, but death often was preceded by a period of clinical disease. Greater morbidity and mortality were observed in swine herds that consumed greater concentrations of aflatoxin.  相似文献   

5.
This research compared the toxic effects of aflatoxin B1 and monocrotaline, the active principle of Crotalaria spectabilis, and the additive effect between aflatoxin B1 and monocrotaline in turkey poults. It was of interest whether selenium fed at dosage levels of 0.1, 5, or 10 micrograms/g of feed would protect against the toxic effect of aflatoxin and/or monocrotaline, and whether the toxicants would result in detectable residues in poult tissues. A total of 180 healthy 1-day-old male turkey poults was assigned at random to 12 treatment groups (15 birds/group). Body and liver weight losses, and low serum concentrations in total protein (TP), albumin (A), alpha-globulin (alpha G), and beta-globulin (beta G), as well as high values in gamma-globulin (gamma G), were produced in the groups fed crotalaria. Pathologic changes were induced by monocrotaline with no protection afforded by the added selenium. Low values in TP, A, alpha G, and beta G and in body and liver weights were observed in groups given the combination of aflatoxin plus crotalaria. Gross lesions were associated with an additive toxic effect and a lack of protective effect of selenium against this combination. However, higher values in TP, A, alpha G, and beta G, and liver weights in groups fed aflatoxin B1 plus selenium indicated that selenium had a protective effect against aflatoxin toxicity. Residues of aflatoxin B1 and aflatoxin M1 were found in the kidneys of poults fed aflatoxin B1; also, dehydroretronecine (the metabolite of monocrotaline) was detected in livers of poults fed Crotalaria spectabilis seeds.  相似文献   

6.
[目的]为快速、准确检测出生鲜牛乳中黄曲霉毒素M1,保证牛奶卫生安全。[方法]采用SNAP黄曲霉毒素M1快速检测试剂盒检测生鲜牛乳中黄曲霉毒素M1。在2012年4月、9月和2013年6月分别对新疆巴州辖区内16个奶站的奶缸、奶牛养殖小区、运输车辆分别抽16份生鲜乳样品检测黄曲霉毒素M1。[结果]16份生鲜乳样品中检测黄曲霉毒素M1,结果全部为阴性。[结论]对巴州辖区内16个奶站的奶缸、奶牛养殖小区、运输车辆进行了生鲜牛乳黄曲霉毒素M1抽样检测项目,16份生鲜牛乳样品结果全部为阴性,未检出黄曲霉毒素M1,合格率为100%。  相似文献   

7.
The two possible pathways contaminating milk and milk products with mycotoxins are either the secretory or post-secretory route. The latter is of only little importance due to cooling conditions in production and storage. A secretory contamination can only occur with such mycotoxins, which undergo no complete degradation through their passage into the milk. From the mycotoxins, present in cow's feed; virtually only aflatoxin B1 yields a milkborne metabolite, the aflatoxin M1. The carry over rate is low (2 +/- 1%), but can be enhanced by polyhalogenated biphenyls, also present in the forage. Under normal conditions, however, this enhancement will not be measurable due to low equimolar concentrations of both reactants. The aflatoxin M1 content in herd's bulk milk depends exclusively on the content of the precursor aflatoxin B1 in the ration of the cow and is with less than 10 ng/kg fairly low at present in the Federal Republic of Germany. A careful supervision of the imported feed ingredients for mixed feed, however, will ensure to keep those batches out of dairy cow feeding which exceed a certain level of aflatoxin. The legal threshold is 10 micrograms/kg, being even too high to ensure a milk containing less than 10 ng/kg under high energy feeding conditions. The discussed thresholds for aflatoxin M1 in milk are 50 and 10 ng/kg resp., the latter value is scheduled for milk used in infant nutrition. To keep this low concentration the intake of aflatoxin B1 must be less than 2 micrograms/kg of the daily ration.  相似文献   

8.
本研究旨在应用胶体金免疫层析技术,结合胶体金定量读数仪研制出一种快速定量检测谷物和饲料中黄曲霉毒素B_1含量的胶体金快速定量检测试剂盒。该试剂盒以胶体金标记高特异性单抗,与偶联抗原进行正交试验,确定适宜条件,同时通过与对照线和试验线的颜色对比,应用胶体金定量读数仪,对样本中黄曲霉毒素B_1含量进行定量检测。结果表明,黄曲霉毒素B1胶体金快速定量检测试剂盒检测方法简便、快速、稳定性好,且可得出具体数据,避免了人肉眼观察的差异;与常见霉菌毒素无交叉反应,样品检测结果与高效液相色谱法检测结果的相对误差在20%以内。由此可见,本试验研制的黄曲霉毒素B_1胶体金快速定量检测试剂盒可用于谷物和饲料中黄曲霉毒素B_1含量的快速定量检测。  相似文献   

9.
Two of 3 groups of Holstein-Friesian steers (groups II and III; n = 5 each) were fed a ration containing corn naturally contaminated with 800 ng of aflatoxin/g. The other group of steers (group I; n = 5) was fed a ration containing noncontaminated corn. The respective rations were fed for 17.5 weeks, except the ration given to group III; the latter's first diet (contaminated with aflatoxin) was changed to a noncontaminated diet after 15 weeks, continuing for the remaining 2.5 weeks. All steers were killed and tissues and fluids were obtained for aflatoxin analysis. Although aflatoxin B1 and M1 could be detected in blood and urine at several sampling times during the experimental period in groups II and III steers (given the diets containing aflatoxin), there appeared to be no effects on body weight gains and immune phenomena, such as lymphoblastogenesis and antibody production, but there was a waning of the delayed cutaneous hypersensitivity in steers given aflatoxin-contaminated diets. In group III animals (diet was changed to noncontaminated ration at 15 weeks), aflatoxin B1 and M1 disappeared from urine before they were slaughtered. All tissues and fluids, except the rumen contents from these group III steers, were void of detectable aflatoxins B1 and M1 at necropsy. The concentrations of aflatoxin B1 in the rumen content of the latter steers were low. All tissues collected at necropsy from the group II steers fed the aflatoxin diet throughout the 17.5 weeks had detectable aflatoxins B1 or M1 present.  相似文献   

10.
The efficacy of melatonin co-administration on aflatoxicosis in chicks was investigated. Ross PM3 breed chicks were divided into groups of 10 and given conventional feed. One of the groups was kept as a control (C), and the others were given 150 ppb aflatoxin (AF1), 300 ppb aflatoxin (AF2), 150 ppb aflatoxin plus 10 mg/kg/bwt melatonin (AF1+M), 300 ppb aflatoxin plus 10 mg/kg/bwt melatonin (AF2+M), 10 mg/kg/bwt melatonin (M), and 1% ethanol (E). After 21 day-treatment period, the chicks were sacrificed, liver and kidney tissues were collected, processed for immuno-histochemical staining, in situ TUNEL method, and biochemical analyses. Vacuolar degeneration, necrosis, bile duct hyperplasia in liver, and mild tubular degeneration in kidney were detected in AF groups. Pathological changes were markedly reduced in AF+M groups, and a microscopic view similar to group C was observed. Increased immunoreactivity against inducible nitric oxide synthase (iNOS) and nitrotyrosine was detected in AF groups compared to weak immunoreactivity in group C. Immunoreactivity in AF+M groups was markedly reduced compared to AF groups and was similar to group C in liver and kidney. Many apoptotic cells were detected in the livers of AF groups, whereas there were no apoptotic cells in AF+M groups. While reduced glutathione (GSH) levels in liver and kidney of AF groups were greatly reduced, malondialdehyde (MDA) levels increased. With melatonin co-administration, the levels of GSH and MDA approached to the values of group C. These results indicated that nitrosative tissue degeneration caused by aflatoxin could be greatly reduced by melatonin supplementation in chicks.  相似文献   

11.
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.  相似文献   

12.
随机抽取3家不同规模奶牛场饲料原料及自配料32份,采用进口ELISA试剂盒检测黄曲霉毒素、玉米赤霉烯酮、赭曲霉毒素和呕吐毒素等4种常见霉菌毒素含量。结果表明：所检测的4种霉菌毒素在所有样品中的检出率为100％,并同时含有2～3种霉菌毒素。其中,除豆粕、苜蓿干草、稻草、豆腐渣外,几乎在所有的饲料样本中玉米赤霉稀酮含量都超标,青贮玉米最高,超标4倍,TMR饲料中玉米赤霉酮含量超出了2倍以上;玉米副产品GGDS中赭曲霉毒素、玉米赤霉酮含量超标严重,呕吐霉素存在微量或少量超标;黄曲霉毒素在青贮玉米、稻草、豆腐渣中有超标,占总样品的15．63％。  相似文献   

13.
旨在建立检测饲料中黄曲霉毒素B1、B2、G1、G2含量的高效液相色谱分析方法。样品用甲醇溶液提取,利用免疫亲和柱净化,以C18反相色谱柱分离,光化学衍生器衍生后应用荧光检测器检测。结果表明:4种黄曲霉毒素在0.5~20ng/mL范围内呈现良好的线性关系,回收率为71.6%~89.0%。采用该方法检测5种饲料样品中的黄曲霉毒素总量,检出率范围在74.0%~86.7%,检出值的范围为0.5~4.3μg/kg。建立的方法精密度高、重复性好,为监测饲料中黄曲霉毒素含量水平提供了有效的分析方法。  相似文献   

14.
We examined 110 dogs, imported or born to imported females or living together with imported dogs in kennels, for the presence of Dirofilaria immitis, and assessed the climatic conditions in the Czech Republic that may promote spread of the disease. Relevant techniques were used to detect specific antigen, specific antibodies and microfilariae. The presence of antigen was detected in one imported dog, microfilariae were not found and antibodies were detected in 30.5% of the imported dogs. No heartworm was found in dogs, which did not travel outside of the Czech Republic. The evaluation of temperature charts showed that it was possible for at least one heartworm generation to develop under climatic conditions in the Czech Republic.  相似文献   

15.
The nature, occurrence and effects of nephrotoxic mycotoxins are considered at their different levels of involvement in animal renal disease. The four associated with field outbreaks of nephrotoxicosis, viz. ochratoxin A, citrinin, aflatoxin and oxalic acid are mainly produced by Aspergilli and Penicillia in grain and other crops, e.g. peanuts. Ten nephrotoxins detected by experimentation including cyclopiazonic acid, penicillic acid and viridicatumtoxin, may also eventually be found to play a role in these diseases. Thirteen fungi frequently isolated from foodstuffs have produced renal (mostly tubular) lesions on the feeding of cultures to animals, in the absence of known nephrotoxins. The pathological changes reported have been predominantly in the proximal tubules with profound cytoplasmic and nuclear effects. The relationship of porcine nephropathy (due to ochratoxin A) to Balkan Nephropathy and the associated urinary tract tumours in man is discussed and the close parallel to the carcinogenic hepatoxicity of the aflatoxins indicated.  相似文献   

16.
Aflatoxicosis was diagnosed as the cause of deaths in a group of crossbred feeder steers. Corn used in the ration being fed the steers was found to be contaminated with 1,500 ng of aflatoxin/g. Residues of the mycotoxin were detected in kidney tissue, and microscopic examination of liver sections revealed lesions typical of aflatoxicosis.  相似文献   

17.
It is well known that cattle ingesting aflatoxin B1 contaminated feed commodities excrete aflatoxin M1 into their milk. As aflatoxin M1 originates from hepatic metabolism, measures to prevent aflatoxin M1 formation need to be directed to either the immobilization of aflatoxin B1 in the gastrointestinal tract or the modification of hepatic metabolism of aflatoxin B1. Here we studied the influence of oltipraz and a second dithiolthione, (1,2) dithiolo (4,3-c)-1,2-dithiole-3,6 dithione (DDD) on bovine hepatic aflatoxin B1 biotransformation. Oltipraz inhibited aflatoxin B1 metabolism as no aflatoxin M1 and no aflatoxin B1-dihydrodiol, the second metabolite found in bovine hepatocytes, was formed. DDD did not significantly inhibit aflatoxin B1 metabolism. It could be demonstrated that the inhibition of aflatoxin B1 metabolism was due to the inhibition of several cytochrome P450 enzyme activities by oltipraz. In contrast, DDD inhibited only ethoxyresorufin O-deethylation activity. These findings suggest a high efficacy of oltipraz in inhibiting aflatoxin M1 contamination of milk from dairy cows exposed to aflatoxin B1 contaminated feeds.  相似文献   

18.
Mycotoxin interactions in poultry and swine   总被引：2，自引：0，他引：2  
Mycotoxins are toxic compounds produced by fungi. When one mycotoxin is detected, one should suspect that others also are present in a contaminated feed ingredient or finished feeds. The toxicity and clinical signs of observed in animals when more than one mycotoxin is present in feed are complex and diverse. Some mycotoxins, such as the combination of aflatoxin with either ochratoxin A or T-2 toxin, interact to produce synergistic toxicity in broiler chicks. The effects observed during multiple mycotoxin exposure can differ greatly from the effects observed in animals exposed to a single mycotoxin. For example, fatty livers in poultry are used for presumptive diagnostic identification of aflatoxicosis. However, simultaneous presence of ochratoxin A prevents fatty livers. Of the mycotoxin combinations that have been investigated in poultry and swine, the aflatoxin + ochratoxin A and aflatoxin + T-2 toxin interactions appear to be the most toxic.  相似文献   

19.
通过7日龄樱桃谷鸭饲喂黄曲霉毒素(AFB1)含量为150 bbp的全价饲料,复制雏鸭感染黄曲霉毒素急性中毒病例,观察中毒鸭的临床症状;于6、12、24、48、72、96、120、144、168和192 h分别剖杀2只,观察大体病理变化,并用ELISA试剂盒测定血液、肝脏中的AFB1含量.黄曲霉毒素急性中毒病例的临床症状主要为:生长停滞,跛行,运动失调,死前呈角弓反张等神经症状.剖检病理变化主要为:气囊混浊有黄色纤维素样渗出物,肝脏肿大呈土黄色,质地变脆并有出血点.饲喂黄曲霉毒素饲料6 h后即可从血液、肝脏中检出AFB1,随着饲喂黄曲霉毒素饲料时间的延长,血液、肝脏中AFB1的含量逐渐增高,7d时肝脏和血清中的AFB1分别高达53.4 ng/g和35.68 ng/g.  相似文献   

20.
The metabolic activity of a mammary epithelial cell line (BME-UV1) was evaluated on monolayers exposed, in serum free medium, to different concentrations (2-4-8 muM) of aflatoxin B1 (AFB1), a mycotoxin eliminated into milk especially as hydroxylated metabolite aflatoxin M1 (AFM1). After 4, 8, 12, 24 h of treatment, a dose and time dependent production of AFM1 has been detected. As the enzymes involved in the hydroxylation of AFB1 in bovine hepatocytes are mainly CYP1A and CYP3A, the results suggest that BME-UV1 express CYP450 isoenzymes which metabolize AFB1 thus representing a potential model for the investigation of the metabolic activity of bovine mammary epithelial tissue.  相似文献   

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