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1.
Mycotoxins: their implications for human and animal health   总被引：7，自引：0，他引：7  
Mycotoxins contaminate various feed and food commodities, due to the global occurrence of toxinogenic molds. They exert adverse health effects in human and animals. The nature of these toxic effects varies depending on the chemical structure of the toxin. The degree of these adverse effects is not only determined by the toxin concentration present in foods and feeds, but also by the time of exposure. Whilst in animals, next to acute intoxication, losses in productivity, reduced weight gain and immunosuppression are considered as most important feature of mycotoxicoses, genotoxic effects and the involvement of certain mycotoxins such as aflatoxin, ochratoxins and fumonisins in the etiology of human cancers have obtained particular attention. This implies that recent research activities concentrate on mechanistic aspects of mycotoxin-induced pathologies, rather than compiling analytical measures of mycotoxin concentrations in food and feeds.  相似文献   

2.
真菌毒素是真菌在食品或饲料中生长所产生的代谢产物,这些低分子质量化合物既是天然存在的,同时也是无法避免的。真菌通过两种途径进入食物链,一方面可以直接从受真菌毒素污染的植物性食品成分进入食物链;另一方面也可以通过食物中产毒真菌生长的间接污染进入食物链。真菌毒素广泛存在于成熟的玉米、谷物、大豆、高粱、花生和饲料作物中。食用受真菌毒素污染的食物或饲料会对人和动物造成急性或慢性毒性。真菌毒素除了有直接食用受霉菌毒素污染的食物和饲料造成的不良影响外,还有因为摄入动物源性食品,如肉类、牛奶或鸡蛋,含有真菌毒素的残留物或代谢物而引起的公众健康问题。目前虽然已经鉴定出超过400种真菌毒素,但食物中广泛存在的6种毒素：黄曲霉毒素、赭曲霉毒素、玉米赤霉烯酮、伏马菌素、呕吐毒素及T-2毒素,已在世界范围内引发了持续的食品安全问题。该论文总结了6种真菌毒素的毒性,重点分析了近年来电化学生物传感器在这几种真菌毒素检测中的研究进展,旨在通过一系列的总结分析去展望其在真菌毒素检测方面的发展前景。  相似文献   

3.
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   

4.
T-2毒素是一种毒性作用很强的霉菌毒素,是以镰刀菌属为主要产毒菌株所产生的一种A类单端孢霉烯族毒素,在多种谷物中的污染水平较高,通过食物摄入后在人类和动物机体内产生一系列毒性作用,严重威胁人类和动物的健康。论文从T-2毒素的理化性质、产毒菌株、毒性作用及对细胞凋亡的作用机制进行了简述,重点介绍了T-2毒素在免疫系统、消化系统和肝脏毒性、神经和皮肤毒性、血液毒性、生殖毒性方面的研究进展,以及T-2毒素通过线粒体信号通路介导细胞凋亡机制的研究进展,为T-2毒素的深入研究提供参考。  相似文献   

5.
Ochratoxin A (OA) is a toxin that contains an isocoumarin moiety linked by a peptide bond to phenylalanine. It is produced by certain Penicillium (mainly P. verrucosum) and Aspergillus (mainly A. alutaceus) species of storage fungi. Total amounts of OA and other related toxins produced by these fungi are influenced by many factors. Several forms of OA have been discovered, some of which are highly toxic, whereas others have lower toxicity. Ochratoxin A has been detected in foods, feeds, animal tissues, and human blood in both Europe and North America. It has been implicated in the fatal human disease Balkan endemic nephropathy, has been shown to be a powerful carcinogen in rodents, and produces many other adverse effects in animals. It is absorbed passively throughout the gastrointestinal tract and in an active manner in the kidney. It is subjected to intestinal secretion and reabsorption via enterohepatic recycling. Binding of OA in the blood to the albumin fraction and recycling in the bile and kidney contributes to its long half-life in animals. Ochratoxin A is hydrolyzed to its nontoxic alpha form (O alpha) by microorganisms in the rumen, cecum, and large intestine. The toxin is excreted primarily in the urine as O alpha and to a lesser degree as OA; smaller amounts of OA and O alpha are generally excreted in the feces. Three distinct mechanisms of OA toxicity have been proposed; other toxic effects of OA seem to be secondary in nature. Several different strategies can be employed for controlling or neutralizing the effect of OA, including the use of proper storage conditions, the use of specific adsorbents to reduce absorption of OA, and the feeding OA-contaminated feedstuffs to ruminants. Antioxidants such as ascorbic acid have been shown to reduce the toxic effects of OA in laying hens. In summary, OA contamination of cereal food and feed may occur, given appropriate conditions. Implementation of suitable procedures may eliminate or minimize this potentially serious problem.  相似文献   

6.
Modern agriculture and production animal medicine require attention to high-quality feeds that are free from mycotoxin contamination that can cause economically important decreases in productivity. Maintaining current information about effects of mycotoxins on feed intake and growth, reproductive efficiency, and possible immunosuppression aid in effective consultation with livestock producers. Investigation and determination of potential production losses related to mycotoxins should use historical, clinical, laboratory, and experimental information to objectively evaluate whether mycotoxin contamination is clinically relevant. The practicing veterinarian or veterinary consultant can provide valuable clinical and interpretive assistance to producers who may have a real or potential mycotoxin contamination. Thorough diagnostic evaluation of animals, appropriate testing of feeds and forages, and rational consideration of differential diagnoses help to put mycotoxins in the proper perspective as a production-related management problem.  相似文献   

7.
In Poland, occurrence of toxigenic fungi in cereals, foods, feeds and their components as well as mycotoxins accumulation in such material has been studied by numerous teams including our research group for over thirty years since 1969. Mostly cereal kernels and feeds have been examined for presence of toxigenic fungi, their toxigenic potential and natural contamination with mycotoxins. Ochratoxin A, deoxynivalenol, nivalenol and moniliformin were found to be significant contaminants of agricultural products in high percentage of cereal grain samples. The profile of toxic metabolites was similar but the concentration levels of the toxins were lower when compared to already published data of the same climate zone. Zearalenone (ZEA), a nonsteroidal mycotoxin with estrogen-like activity, is synthesized by molds (Fusarium) commonly contaminating poorly stored agricultural products and foodstuffs. Since in the course of examinations and during surgical procedures performed in dogs, ovarian cysts were detected and because frequently this is the first stage of the endometrica pyometra complex (EPC) found in approximately 30% of the females we assume that both factors, mycotoxins (ZEA) and pathological aberrations are possibly related in these animals. Similar activity of the toxin (possibly present in pelleted dog feed) and effects including infertility of female dogs is speculated with indication and suggestion on necessity of additional studies on the problem.  相似文献   

8.
BackgroundThe administration of metronidazole in chinchillas remains controversial and some sources raise concerns regarding drug-induced anorexia or hyporexia. Therefore, the objective of this study was to evaluate if the oral administration of oral metronidazole has a significant effect on food intake in clinically healthy chinchillas, and if drug-induced reduction of food intake differs between metronidazole and metronidazole benzoate as well as between different concentrations of metronidazole benzoate suspensions.MethodsIn a series of randomized, blinded, crossover experiments, the effects of oral administration of metronidaole at 20 mg/kg was evaluated following q12h (for 3 days, n = 12) or q24h (for 5 days, n = 9) dosing using two different drug compounding protocols.ResultsFollowing administration of metronidazole, food intake was significantly reduced within 24 hours of drug administration, regardless of drug formulation type, compounding protocol, or drug concentration. Variation in metronidazole-induced food intake reduction differed widely between individual chinchillas, with a reduction of >50% of food intake reported in 50% of the animals following q12h administration, and 33% of animals after q24h administration of metronidazole. The reduction in food intake was self-limiting and return to normal food intake occurred after discontinuation of metronidazole administration. Neurological adverse effects were observed in one animal following q12h administration.Conclusions and clinical relevanceThe oral administration of metronidazole and metronidazole benzoate at published dosages can result in a marked reduction in food intake, and therefore, this drug should be used cautiously in chinchillas and food intake carefully monitored.  相似文献   

9.
Implications of mycotoxins in animal disease   总被引：7，自引：0，他引：7  
Mycotoxins are formed on animal feeds when conditions of moisture and temperature permit the growth of naturally occurring toxigenic fungi. In general, mycotoxins are low molecular weight, nonantigenic substances, many of which are relatively heat stable. Mycotoxins can cause acute disease episodes when animals consume critical quantities of them. Specific toxins affect specific organs or tissues such as the liver, kidney, oral and gastric mucosa, brain, or reproductive tract. In acute mycotoxicoses, the signs of disease often are marked and directly referable to the affected target organs. Most frequently, however, concentrations of mycotoxin in feeds are below those that cause acute disease. At lower concentrations, the effects of mycotoxins are more protean. They reduce the growth rate of young animals, and some interfere with native mechanisms of resistance and impair immunologic responsiveness, making the animals more susceptible to infection. These effects on immunity and resistance are difficult to recognize because the signs of disease are associated with the infection rather than with the mycotoxin that predisposed the animal to infection. Animals vary in their susceptibility to some mycotoxins, according to the species and age of animal; young growing animals are more susceptible to certain mycotoxins than are adults. The major effects, sources, and dose response relationships of mycotoxins important to the health of food-producing animals are presented in accompanying tables.  相似文献   

10.
Abstract

The objectives of the present study were to evaluate the effects of different concentrations of the mycotoxin T-2 toxin in feed on muscle performance in the Pacific white shrimp Litopenaeus vannamei, evaluate indexes of physiological variables that indicate T-2 toxin contamination in the shrimp using the grey relational method, and determine the dose–response relationships between T-2 toxin and the indexes. Of the 6 physical, 7 biochemical, and 17 nutritional indexes examined, the values of the grey relational coefficients were highest for the hepatopancreas: body weight ratio (HBR), alanine aminotransferase (ALT) activity, and serine (SER) content (0.83, 0.68, and 0.82, respectively). Therefore, the HBR, ALT activity, and SER content were selected as appropriate indexes for contamination of Pacific white shrimp muscle with T-2 toxin. Based on their dose–response relationship curves, mean effective doses of 1.45, 1.69, and 1.33 mg of T-2 toxin/kg of feed were obtained for the HBR, ALT activity, and SER content, respectively. These results offer technical reference points for the evaluation and control of T-2 toxin in shrimp feed.

Received April 28, 2016 accepted April 9, 2017 Published online July 26, 2017  相似文献   

11.
Mycotoxin-producing fungi may contaminate agricultural products in the field (preharvest spoilage), during storage (postharvest spoilage), or during processing. Mycotoxin contamination of foods and feeds poses serious health hazard to animals and humans. For lowering mycotoxin contamination of feeds and foods, several strategies have been investigated that can be divided into biological, chemical and physical methods. This paper gives an overview of strategies which are promising with regard to lowering the mycotoxin burden of animals and humans.  相似文献   

12.
Several species of fungi, which infect cereals and grains, can produce a class of compounds, known as trichothecene mycotoxins, which is characterized by a substituted epoxy-trichothecene ring structure. Cattle are susceptible to intoxication from feeds contaminated with T-2 toxin, one of the more potent trichothecene mycotoxins, while swine refuse to ingest feed contaminated with T-2 toxin. The bovine platelet has been used as a model cell system to evaluate the effects of T-2 toxin and its natural metabolites, HT-2 toxin and T-2 tetraol, on cell function in vitro. Due to the lipophilic nature of these mycotoxins, a biologically active phospholipid was used to stimulate the platelets in the presence and absence of the toxins. The mycotoxin T-2 toxin and its major metabolite HT-2 toxin inhibited platelet activating factor-stimulated bovine platelets, suspended in homologous plasma, in a concentration but not time dependent manner. Significant inhibition of platelet function (p less than 0.01) occurred with 135 ng T-2 toxin per 10(6) platelets and with 77 ng HT-2 toxin per 10(6) platelets. These mycotoxins exerted an additive inhibitory effect on the platelet aggregation response. In contrast, the minor metabolite T-2 tetraol had no inhibitory effect on platelet function and had no influence on the responses of T-2 toxin or HT-2 toxin when the mycotoxins were present together in the platelet suspensions.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

13.

Background

The current study was carried out to provide a reference for the control of mycotoxin contamination in feed ingredients and complete feeds for swine.

Methods

A total of 55 feed ingredients, including 14 corn, 13 wheat bran, 11 soybean meal and 17 dried distillers grains with solubles (DDGS) as well as 76 complete swine feeds including 7 creep feeds, 14 starter feeds, 14 grower feeds, 18 grower-finisher feeds, 10 gestating sow feeds, and 13 lactating sow feeds were randomly collected from 15 swine farms located in the Beijing region of China from July to August 2011. Immunoaffinity clean-up, using High-Performance Liquid Chromatography (HPLC) in combination with UV or Fluorescence Detection, was used for quantitative analysis of aflatoxin B1 (AFB1), deoxynivalenol (DON), zearalenone (ZEA) and ochratoxin A (OTA) in the ingredients and complete feeds.

Results

DON and ZEA were the most prevalent mycotoxins found. DON was detected at percentages of 93, 92, 54, 100 and 97% with a mean level of 1.01, 0.44, 0.05, 1.36 and 0.65 ppm in the samples of corn, wheat bran, soybean meal, DDGS and complete feeds, respectively. The detected percentages of ZEA were 100, 100, 54, 100 and 100 with mean levels of 109.1, 14.9, 9.2, 882.7 and 58.9 ppb in the same samples. In the wheat bran and soybean meal samples, the content of all four mycotoxins were below the maximum limits set by Chinese regulations while the percentage of samples that exceeded regulatory limits were 7, 57 and 7% for corn, and 7, 14 and 3% for the complete feeds for AFB1, DON and OTA respectively. DDGS showed the most serious mycotoxin contamination and the percentage of samples that exceeded regulatory limits were 6, 88 and 41%, for AFB1, DON and ZEA, respectively.

Conclusions

This paper is the first to present data on the natural occurrence of AFB1, DON, ZEA and OTA in ingredients and complete feeds obtained from swine farms in China’s Beijing region. The data shows that feed ingredients and complete swine feeds obtained from these farms are most often contaminated with DON followed by contamination with AFB1 and ZEA.  相似文献   

14.
From the point of view of human exposure, fumonisins (FB1, FB2, FB3, FB4), a relatively recently (1988) discovered and identified group of mycotoxins, represent one of the five most important mycotoxin groups causing human disease. In an earlier experiment studying the effects of relatively low doses (10, 20 and 40 p.p.m.) of FB1 in weaned piglets, it was established that the 4‐week feeding of 10 p.p.m. (mg/kg feed) FB1 produced mild pulmonary oedema. This suggested the importance of studies with even lower doses of the toxin to determine the tolerable limits. The objective of this experiment was therefore to study the effects of prolonged (8‐week) exposure to still lower concentrations (0, 1, 5 and 10 mg/kg feed) of FB1. The 8‐week feeding of FB1 in low concentrations (1–10 p.p.m.) did not cause clinical signs and significant performance impairment in pigs, but rendered irreversible the chronic changes that had already developed in the animals in a dose‐dependent manner. Dissection revealed pathological alterations of the lungs in one of the animals given 1 p.p.m. (n=4), in two animals exposed to 5 p.p.m. (n=5), and in three animals given 10 p.p.m. (n=4). In all three treatment groups, proliferation of the connective tissue fibres, primarily of those around the lymphatic vessels, in the subpleural and interlobular connective tissue of the lungs, extending to the peribronchial and peribronchiolar areas, was seen. The results of this experiment call attention to the risk of prolonged low‐dose toxin exposure, which has very important public health implications.  相似文献   

15.
Fumonisin B1 (FB1) is a mycotoxin produced by Fusarium moniliforme and F. proliferatum. Little is known of its metabolic fate after oral ingestion in ruminants, but these animals are reported to be tolerant towards FB1. The metabolism of this mycotoxin was evaluated following incubation (1 g/ml) in ruminal fluid for up to 72 h, in the presence or absence of alfalfa as a substrate for microbial growth, using a model rumen (sealed flask, anaerobic conditions, exclusion of light, gentle agitation, 39°C). The decrease in FB1 concentration and the production of short-chain fatty acids were determined. FB1 had no effect on SCFA production. After 72 h incubation, FB1 depletion was 12% and 18% in samples with and without alfalfa, respectively. No hydrolysed metabolites (aminopolyols or aminopentol) were detected. These results indicate that FB1 is poorly metabolized in the rumen and suggest that such metabolism is not the cause of the tolerance to this toxin displayed by ruminants.  相似文献   

16.
2006~2007年中国饲料及饲料原料霉菌毒素污染调查报告   总被引：15，自引：1，他引：14  
作者评估了2006年和2007年上半年我国饲料原料和全价饲料中6种主要霉菌毒素的检出水平和分布特点,得出如下结论：①我国饲料原料和全价饲料中超标率和检出水平最高的霉菌毒素是玉米赤霉烯酮、烟曲霉毒素和呕吐毒素（田间型毒素）。人们一直重视的黄曲霉毒素（仓储型毒素）超标率和检出水平均比较低;②饲料原料和全价饲料中多种霉菌毒素往往同时存在,由于不同毒素间具有协同作用,将加剧毒素的毒性作用和中毒症状的严重程度;③副产品原料,特别是玉米副产品如干燥酒糟（DDGS）和玉米蛋白粉中霉菌毒素的污染非常严重;④与单一能量和蛋白质饲料原料相比,全价饲料中的多种霉菌毒素的检出水平才是相对比较准确和客观的控制指标;⑤控制霉菌毒素危害的最经济有效的措施是控制原料质量和使用有效的霉菌毒素吸附剂。  相似文献   

17.
探讨橙皮苷对3种霉菌毒素处理的HepG2细胞增殖和迁移作用的影响。采用MTT、Griess、细胞划痕愈合试验分别检测细胞活力、细胞分泌NO、细胞迁移率。结果3种毒素对HepG2细胞增殖的影响随毒素浓度的增加呈现先促进后抑制的作用,低浓度DON、OTA(0.04μmol/L和0.08μmol/L),ZEN(<2μmol/L)显著提高HepG2细胞活力及促进增殖,高浓度霉菌毒素明显降低HepG2细胞活力及抑制细胞增殖。与霉菌毒素组比较,橙皮苷组HepG2细胞活力降低及增殖减弱,表示橙皮苷能缓解霉菌毒素对细胞的毒性。与空白对照组比较,霉菌毒素组HepG2分泌NO量显著降低,不同浓度及不同霉菌毒素对NO分泌没有明显影响;与霉菌毒素组比较,橙皮苷组不同浓度DON处理的细胞分泌NO差异不显著。低浓度DON毒素(0.08μmol/L^2μmol/L)处理HepG2细胞24、36、48 h后,DON毒素能极显著促进HepG2细胞迁移,随着霉菌毒素对细胞处理时间延长细胞迁移快,而高浓度DON毒素(10μmol/L、50μmol/L)对促细胞迁移影响显著低于低浓度DON。结果低浓度DON霉菌毒素促进HepG2细胞增殖及迁移,表明DON毒素对HepG2具有潜在的致癌性,橙皮苷能抑制HepG2细胞增殖及缓解霉菌毒素毒性的作用。  相似文献   

18.
ABSTRACT

1. Peripheral blood immune evaluation of broilers by flow cytometry is commonly used in avian research. However, indicative immune parameters in healthy animals have not yet been determined. In this trial, confidence intervals were determined for several circulating immune cell subsets.

2. The intervals were determined from over 1,000 healthy broilers from commercial lines. To verify the usefulness of the data, they were compared to animals under salmonellosis or mycotoxin challenges.

3. Confidence intervals were determined for several immune cells in the peripheral blood of broilers. The importance of some immune cells in discriminating diseased from healthy controls was demonstrated.

4. This work initiated the construction of reference values for cellular parameters in broilers as a tool for the avian immunology community. Accordingly, the entire dataset of healthy animals was made available for use with other analyses and for improvement by others.  相似文献   

19.
Summary

Antimicrobials given in subtherapeutic levels in feed are credited with having contributed to lower cost of meat, milk and eggs. The practice often is associated with the acquisition of resistant enteric flora by the involved animals, and this may in turn contribute to the human reservoir of antimicrobial resistant coliforms and salmonellae. Associated farm workers may transiently acquire resistant flora and on rare occasions develop salmonellosis. Although irrefutable evidence of growth promotant properties of antibiotics in animal feed was provided 30 to 40 years ago, additional studies on mechanisms of the effect are presently needed. It may be possible to identify factors effective in promoting growth without deleterious effects on flora. A national surveillance programme of antimicrobial utilisation (both subtherapeutic and therapeutic) among food producing animals should be established. Molecular epidemiologic research efforts will need to be undertaken to establish whether genetic information of animal origin importantly contributes to the human environmental pool of antimicrobial resistance. In the meantime, it does not appear that the use of drugs as feed additives, while allowing their unrestricted use for therapy in both animals and persons, wouldfavorably influence the problems of antimicrobial resistance of salmonellosis in human populations.  相似文献   

20.
BackgroundMidazolam has been shown to increase food intake in budgerigars. However, its effect on appetite beyond one hour after administration is unknown. Lorazepam is a longer-acting benzodiazepine and may provide more sustained appetite-stimulating effects in birds, but currently, no information on its appetite or sedative effects in budgerigars is available.MethodsIn a randomized, placebo-controlled, blinded, complete crossover study, the effects of midazolam (1 mg/kg IM) or lorazepam (1 mg/kg IM) were compared to a control treatment (1 ml/kg sterile water IM) in healthy adult budgerigars (n = 22). Food intake was measured for one hour before and twelve hours after drug administration. Behavioral changes and adverse effects were monitored by video recording.ResultsCompared to the control treatment, food intake increased significantly following midazolam and lorazepam administration in the first hour after drug administration. The total amount of food ingested over time was significantly higher for the first five hours after midazolam or lorazepam administration compared to the control treatment. Sedation occurred for the first three hours after drug administration with both drugs. There was no clinical or statistical significance difference between lorazepam and midazolam regarding appetite stimulation or sedative effects in this study.Conclusions and clinical relevanceBoth midazolam and lorazepam are potent, short-acting appetite stimulants in budgerigars. To induce a sustained increase in food intake, the repeated administration of these drugs would be required. The use of lorazepam does not appear to provide any advantages compared to the more widely available and frequently used midazolam in budgerigars.  相似文献   

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