RESUMO
Paddy is an important crop in Malaysia. There are various pathogens able to infect paddy causing a loss in yields production. In this study, dual culture method, volatile organic compound (VOC) analysis, and non-volatile compound analysis were used to assess the ability of mushroom to control fungal rice pathogens including Curvularia lunata, Bipolaris panici-miliacei, and Nigrospora sp. Four mushroom isolates were further analysed for their antagonistic activity against rice pathogen. The highest percentage inhibition of radial growth (PIRG) was recorded between 45.55 and 73.68% observed in isolate 42b. The 4 isolates with the highest PIRG based on the dual culture analysis were then tested for their production of VOCs and non-volatile compound. Internal transcribed spacer (ITS) region analysis of the 4 mushroom isolates revealed their identity as Coprinellus disseminates (isolate 12b), Marasmiellus palmivorus (isolate 42b), Trametes maxima (isolate 56e), and Lentinus sajor-caju (isolate 60a). This study showed that mushroom isolates have the potential of antagonistic effect on various fungal rice pathogens tested by the production of secondary metabolites and mycoparasitic interaction.(AU)
Assuntos
Humanos , Oryza , Agaricales , Compostos Orgânicos Voláteis , Micotoxicose , Genes Fúngicos , Microbiologia , MalásiaRESUMO
Feeding farm animals with aflatoxin-contaminated feed can cause various severe toxic effects, leading to increased susceptibility to infectious diseases and increased mortality, weight loss, poor performance and reduced reproductive capability. Following ingestion of contaminated foodstuffs, aflatoxins are metabolized and biotransformed differently in animals. Swine metabolism is not effective in detoxifying and excreting aflatoxins, meaning the risk of aflatoxicosis is increased. Thus, it is of great importance to elucidate the metabolism and all metabolic pathways associated with this mycotoxin. The damage induced by AFB1 in cells and tissues consists of inhibition of cell proliferation, carcinogenicity, immunosuppression, mutagenicity, oxidative stress, lipid peroxidation and DNA damage, leading to pathological lesions in the liver, spleen, lymph node, kidney, uterus, heart, and lungs of swine. At present, it is a challenging task and of serious concern to completely remove aflatoxins and their metabolites from feedstuff; thus, the aim of this study was a literature review on the deleterious effects of aflatoxins on swine metabolism, as well as alternatives that contribute to the detoxification or amelioration of aflatoxin-induced effects in farm animal feed.
Assuntos
Aflatoxinas , Micotoxicose , Feminino , Animais , Suínos , Aflatoxinas/toxicidade , Animais Domésticos , Fígado , Micotoxicose/veterinária , Micotoxicose/patologia , Baço , Ração Animal/análiseRESUMO
Mycotoxins are secondary metabolites produced by fungi. Food/feed contamination by mycotoxins is a great threat to food safety. The contamination can occur along the food chain and can cause many diseases in humans and animals, and it also can cause economic losses. Many detoxification methods, including physical, chemical, and biological techniques, have been established to eliminate mycotoxins in food/feed. The biological method, with mycotoxin detoxification by microorganisms, is reliable, efficient, less costly, and easy to use compared with physical and chemical ones. However, it is important to discover the metabolite's toxicity resulting from mycotoxin biodegradation. These compounds can be less or more toxic than the parent. On the other hand, mechanisms involved in a mycotoxin's biological control remain still unclear. Mostly, there is little information about the method used by microorganisms to control mycotoxins. Therefore, this article presents an overview of the most toxic mycotoxins and the different microorganisms that have a mycotoxin detoxification ability. At the same time, different screening methods for degradation compound elucidation are given. In addition, the review summarizes mechanisms of mycotoxin biodegradation and gives some applications.
Assuntos
Micotoxicose , Micotoxinas , Humanos , Animais , Micotoxinas/análise , Contaminação de Alimentos/prevenção & controle , Contaminação de Alimentos/análise , Fungos/metabolismo , AlimentosRESUMO
Aflatoxins are mycotoxins capable of contaminating food, and can cause toxic effects, teratogenicity, mutagenicity, carcinogenicity, and immune system depression. The presence of fungi which produce this metabolite in ingredients that compose the animal feed increased the risk of the emergence of aflatoxicosis. The objective of this study was to report an aflatoxicosis outbreak in rheas (Rhea americana) from a farm in Teresina, PI, Brazil, fed with commercial feed. After the deaths of four animals, epidemiological data were collected and complementary examinations were performed, including necropsy, histopathology, parasitology, blood culture, in addition to the analysis of the presence of toxins in the birds' feed. The diagnosis was based on the acute clinical signs, necropsy findings, which included carcass jaundice, an oedematous, yellowish, friable liver of increased size, and histopathological findings of moderate to severe congestion in all organs. The parasitological and microbiological tests performed were negative, not indicating systemic infectious causes. The analysis of the presence of mycotoxins revealed the existence of Aflatoxins B1, B2 and G1 in the commercial feed supplied, constituting a total of 66.89 µg/kg. This amount of aflatoxin exceeds the maximum level allowed by the Brazilian legislation. To our knowledge this is the first report of aflatoxicosis in rheas, and emphasizes the importance of the diagnosis, control, and prevention of mycotoxins in the quality of food provided to animals kept ex situ.
Assuntos
Aflatoxinas , Doenças Transmitidas por Alimentos , Micotoxicose , Micotoxinas , Reiformes , Aflatoxinas/análise , Aflatoxinas/toxicidade , Ração Animal/análise , Animais , Brasil/epidemiologia , Surtos de Doenças/veterinária , Doenças Transmitidas por Alimentos/veterinária , Micotoxicose/epidemiologia , Micotoxicose/veterinária , Micotoxinas/análiseRESUMO
Bovine fescue toxicosis (FT) is caused by grazing ergot alkaloid-producing endophyte (Epichloë coenophiala)-infected tall fescue. Endophyte's effects on the animal's microbiota and metabolism were investigated recently, but its effects in planta or on the plant-animal interactions have not been considered. We examined multi-compartment microbiota-metabolome perturbations using multi-'omics (16S and ITS2 sequencing, plus untargeted metabolomics) in Angus steers grazing non-toxic (Max-Q) or toxic (E+) tall fescue for 28 days and in E+ plants. E+ altered the plant/animal microbiota, decreasing most ruminal fungi, with mixed effects on rumen bacteria and fecal microbiota. Metabolic perturbations occurred in all matrices, with some plant-animal overlap (e.g., Vitamin B6 metabolism). Integrative interactomics revealed unique E+ network constituents. Only E+ had ruminal solids OTUs within the network and fecal fungal OTUs in E+ had unique taxa (e.g., Anaeromyces). Three E+-unique urinary metabolites that could be potential biomarkers of FT and targeted therapeutically were identified.
Assuntos
Alcaloides de Claviceps , Festuca , Lolium , Micotoxicose , Ração Animal/análise , Animais , Bovinos , Alcaloides de Claviceps/metabolismo , Alcaloides de Claviceps/toxicidade , Festuca/metabolismo , Lolium/microbiologiaRESUMO
A retrospective cohort study was conducted on two Egyptian horse farms with most of horses were suffered from abdominal pain to describe the associations between the occurrence of mycotoxicosis and equine colic. The farms owner complain was an unexpected increase in number of colic cases and deaths among horses. The association between colic and risk factors (sex, type of food either dry or mixed with roughages and hematobiochemical parameters) was compared using independent sample T-test. The associations between possible prognostic indicators for colic caused by mycotoxicosis was estimated using logistic regression analysis model. The cumulative incidence, incidence rates for colic attacks, survival rate among diseased horses were additionally estimated. Our results showed that a total of 24 out of the 132 horses suffered from colic due to feeding of ration contaminated with high percent of mycotoxin including Aflatoxins, Ochratoxins and or fusarium mycotoxins. The total cumulative incidence of colic due to mycotoxicosis was 19.7%. The horses fed on dry rations had more chance of developing colic than horses fed on mixed rations (P < 0.05). The overall incidence rate of colic due to mycotoxicosis was estimated at 18 colic attack/1000 horse/month. The mortality rate of horses suffered from colic due to mycotoxicosis was estimated at 5.9% (5/85), while the case fatality rate was estimated at 25% (n = 5/20). Inconclusion, our results showed that mycotoxicosis are considered an important risks factor for colic cases development in equine practice.
Assuntos
Cólica , Doenças dos Cavalos , Micotoxicose , Animais , Cólica/epidemiologia , Cólica/veterinária , Doenças dos Cavalos/epidemiologia , Cavalos , Micotoxicose/veterinária , Estudos Retrospectivos , Fatores de RiscoRESUMO
AIMS: To assess whether adding glutamate dehydrogenase (GDH) activity measurements to measurements of gamma-glutamyl transferase (GGT) activity appreciably increases the accuracy of diagnosis of subclinical facial eczema (FE) in cattle. METHODS: As part of a larger study on the impact of FE on productivity, GGT and GDH activities were measured in serum samples collected from 426 cattle from one dairy farm in the Taranaki region in April 2018. Bayesian latent class analysis was then used to estimate herd prevalence of subclinical FE as well as the specificity and sensitivity of the activity in serum of GGT or GDH alone, and of GGT and GDH activities combined, as diagnostic tests for subclinical FE. RESULTS: The latent class analysis estimated the true prevalence of subclinical FE in the study population as 47.5 (95% probability interval (PI) = 38.3-55.3)%. There was no evidence of any clinically relevant difference between GGT and GDH activities as predictors of subclinical FE; the difference between the areas under the receiver operating characteristic curves for the two measures was 0.005 (95% PI = -0.02 to -0.03). Using the two tests in parallel, with a threshold of 50 IU/L for GGT and 225 IU/L for GDH resulted in specificity and sensitivity of >95%, markedly increasing the accuracy of diagnosis of subclinical FE compared to using GGT or GDH alone at any threshold. CONCLUSIONS AND CLINICAL RELEVANCE: In this herd, combining the two tests resulted in a clinically relevant improvement in the accuracy of diagnosis of subclinical FE compared to using either test alone, which if used at the individual level will result in fewer cattle being assigned the wrong FE status. This will also apply at the herd level, with combined testing producing fewer false-positive herd test results than using one enzyme alone. This is particularly important for monitoring the efficacy of FE control measures when the expectation should be that the proportion of cattle with FE is very low.
Assuntos
Doenças dos Bovinos , Eczema , Micotoxicose , Animais , Teorema de Bayes , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/epidemiologia , Eczema/diagnóstico , Eczema/veterinária , Fígado , Micotoxicose/veterináriaRESUMO
1. Aflatoxins (AFs) are metabolites which especially have toxic effects on proteins, and are detoxified by the aflatoxin-B1 aldehyde reductase (AFAR) pathway. In this pathway, the aldo-keto reductase family 7, member A2 (AKR7A2) enzyme, which is controlled by nucleic-related erythroid factor 2 (Nrf2), plays an active role. However, data on the efficacy of this critical pathway in broilers is limited.2. The aim of the following study was to investigate the changes in the expression levels of AKR7A2, Nrf2, and caspase-3, and the effects of Nigella sativa seeds (NS), thymoquinone (TMQ), and bentonite (BNT) in broilers exposed to AFs.3. One-hundred broilers were divided into ten groups (control (CNT); AF; NS; TMQ; BNT; AF+TMQ; AF+NS; AF+BNT; AF+BNT+NS; AF+BNT+TMQ) and fed for 28 d. AF, TMQ, NS and BNT were added to diets at levels of 2 mg/kg, 300 mg/kg, 50 g/kg and 10 g/kg respectively.4. The addition of AF to the diet decreased AKR7A2 and Nrf2 levels dramatically, but increased caspase-3 (P < 0.01). TMQ, NS and BNT additions to the diet eliminated all negative effects caused by AF (P < 0.01); and AKR7A2 and Nrf2 were further raised in TMQ and NS groups when compared to the control group. TMQ and NS showed a positive effect on detoxification parameters when given together with BNT.5. Supplementation with NS and TMQ enhanced AF detoxification via the AFAR pathway, by increasing AKR7A2 and Nrf2 levels, in addition to reducing hepatocyte apoptosis.
Assuntos
Aflatoxinas , Doenças Transmitidas por Alimentos , Micotoxicose , Nigella sativa , Aldeído Redutase/genética , Aldeído Redutase/metabolismo , Animais , Bentonita/metabolismo , Benzoquinonas , Caspase 3/genética , Caspase 3/metabolismo , Galinhas/metabolismo , Regulação para Baixo , Doenças Transmitidas por Alimentos/veterinária , Micotoxicose/veterinária , Fator 2 Relacionado a NF-E2/metabolismo , Nigella sativa/metabolismoRESUMO
Mycotoxins in feedstuffs are considered as a principal worry by food safety authorities worldwide because most of them can be transferred from the feed to food commodities of animal origin, and further consumed by humans. Therefore, effective alternatives for the reduction of the impact of mycotoxins need to be applied in the feed production industry. Applications of beneficial microorganisms (probiotics) can be alternative and applied as feed additives in order to reduce or eliminate the toxic effects of mycotoxins on animals. The aim of this article is to provide information on the role of beneficial microorganisms (probiotics) and point out their role in the reduction of the effect of mycotoxin toxicity in farming animals (mammals and poultry). The objective was to provide a summary of the existing knowledge based on the application of different strains belonging to the group of lactic acid bacteria (LAB) or yeasts that are already or can be future employed in the feed industry, in order to reduce mycotoxicosis presence in mammals and poultry exposed to mycotoxin-contaminated feed. Moreover, an overview of mycotoxins toxicity in mammals and poultry will be presented, and furthermore, the role of the beneficial microorganisms (including probiotics) in the reduction of mycotoxins toxicity (aflatoxicosis, deoxynivalenol, zearalenone, ochratoxin A, and fumonisin toxicities) will be described in detail.
Assuntos
Micotoxicose , Micotoxinas , Probióticos , Animais , Humanos , Aves Domésticas , Contaminação de Alimentos , Micotoxinas/toxicidade , MamíferosRESUMO
The aim of the experiment was to investigate the efficacy of a smectite-based clay binder (Toxo-MX) in reducing the toxicological effects of aflatoxin B1 (AFB1) in commercial broiler chickens. A total of 450 one-day old male broiler chickens were randomly allocated into three treatment groups with ten replicates of 15 birds each in a 42-day feeding experiment. The dietary treatments included a negative control (NC, a basal diet with no AFB1 and binder), a positive control (PC, a basal diet contaminated with 500 ppb of AFB1) and a smectite-based mycotoxin binder(Toxo-MX, PC with smectite clay binder). AFB1 challenge resulted in 14 to 24% depression in growth performance, elevated levels of aspartate aminotransferase (AST), and gamma-glutamyl transferase (GGT), organ enlargement and immuno-suppression.As compared to PC, feeding of Toxo-MX improved the final weight (15%; p < 0.0001), average daily gain (ADG) (15%; p < 0.001) and feed efficiency of broilers (13%; p < 0.0003) but did not have any effects on liver enzyme activities. Supplementation of smectite claysignificantly increased serum globulin levels and reduced the weight of the liver (p < 0.05) as compared to AFB1-fed broiler chickens. The severity of lesions (inflammatory and degenerative changes) observed in the liver, kidney, heart, pancreas, and lymphoid organs in PC birds was reduced by feeding smectite clay. The immuno-suppression caused by AFB1 was moderately ameliorated in Toxo-MX groupby stimulating the production of antibodies against IBD at day 42 (p < 0.05). In conclusion, dietary supplementation of a smectite-based mycotoxin binder to the diet containing AFB1 improved growth performance, reduced toxicological effects in liver and improved humoral immune response in broilers, suggesting its protective effect against aflatoxicosis.
Assuntos
Aflatoxina B1/efeitos adversos , Galinhas/crescimento & desenvolvimento , Silicatos/administração & dosagem , Ração Animal/análise , Animais , Aspartato Aminotransferases , Contaminação de Alimentos/prevenção & controle , Fígado/efeitos dos fármacos , Masculino , Micotoxicose/prevenção & controle , Micotoxicose/veterinária , Tamanho do Órgão , Doenças das Aves Domésticas/prevenção & controle , Silicatos/química , gama-GlutamiltransferaseRESUMO
Abstract Mycotoxins contaminate agricultural commodities, which contaminates animals. These toxins can damage vital organs, such as the liver, as well as the epithelial tissue. Among these mycotoxins are aflatoxin B1 (AFB1) and cyclopiazonic acid (CPA), which can occur simultaneously in food. In broilers, mycotoxicosis has an economic impact due to several factors, such as low feed conversion rate, incidence of other diseases, and interference with reproductive capacity, all of which may lead to a public health problem. The aim of the present study was to histologically assess, through the I See Inside (ISI) method, harmful effects on broiler liver, duodenum, jejunum, and ileum in the presence of AFB1 and CPA isolatedly and simultaneously. Groups challenged with mycotoxins showed significant damage to both gut and liver fragments. All challenged-groups in all fragments impaired the parameters analyzed for intestinal epithelium. In the liver, AFB1 was predominantly harmful when the parameters were analyzed separately, but when analyzing the total ISI score, CPA was also found to be harmful to this organ. The other point analyzed was the great variation between the weights of the birds contaminated by mycotoxin while the negative control group presents a lesser variation.
Resumen Las micotoxinas contaminan los productos agrícolas, que a su vez contaminan a los animales. Estas toxinas pueden dañar órganos vitales, como el hígado y el tejido epitelial. Entre estas micotoxinas se encuentran la aflatoxina B1 (AFB1) y el ácido ciclopiazónico (CPA), que pueden hallarse simultáneamente en los alimentos. En los pollos de engorde, la micotoxicosis tiene un impacto económico debido a varios factores, como la baja tasa de conversión alimenticia, la incidencia de otras enfermedades y la interferencia de la capacidad reproductiva, que pueden llevar a un problema de salud pública. El objetivo de la presente investigación es la de evaluar histológicamente, a través del método "I See Inside" (ISI), los efectos nocivos sobre el hígado, duodeno, yeyuno e íleon de pollos de engorde en presencia de AFB1 y CPA de forma aislada y simultánea. Los grupos desafiados con micotoxinas presentaron un daño significativo tanto en el intestino como en los fragmentos del hígado. Todos los grupos tratados tuvieron alteraciones en los parámetros analizados para el epitelio intestinal. En el hígado, AFB1 fue predominantemente dañino cuando los parámetros se analizaron por separado, pero al examinar la puntuación ISI total, también se encontró que el CPA era perjudicial para este órgano. Otra cuestión que fue investigada fue la gran variación entre los pesos de las aves contaminadas por micotoxinas mientras el grupo de control negativo presentó una variación menor.
Assuntos
Animais , Doenças das Aves Domésticas/diagnóstico , Micotoxicose/patologia , Galinhas/anatomia & histologia , Micotoxinas/toxicidadeRESUMO
Mycotoxins can be found in many foods consumed by humans and animals. These substances are secondary metabolites of some fungi species and are resistant to technological processes (cooking, frying, baking, distillation, fermentation). They most often contaminate products of animal (beef, pork, poultry, lamb, fish, game meat, milk) and plant origin (cereals, processed cereals, vegetables, nuts). It is estimated that about 25% of the world's harvest may be contaminated with mycotoxins. These substances damage crops and may cause mycotoxicosis. Many mycotoxins can be present in food, together with mold fungi, increasing the exposure of humans and animals to them. In this review we characterized the health risks caused by mycotoxins found in food, pet food and feed. The most important groups of mycotoxins are presented in terms of their toxicity and occurrence.
Assuntos
Contaminação de Alimentos/análise , Micotoxicose/etiologia , Micotoxinas/toxicidade , Ração Animal/análise , Ração Animal/microbiologia , Animais , Fungos/metabolismo , Humanos , Carne/análise , Carne/microbiologia , Micotoxinas/análise , Metabolismo SecundárioRESUMO
Zearalenone (ZEN) and its metabolites, alpha-zearalenol (α-ZEL) and beta-zearalenol (ß-ZEL), are ubiquitous in plant materials used as feed components in dairy cattle diets. The aim of this study was to confirm the occurrence of ZEN and its selected metabolites in blood samples collected from different sites in the hepatic portal system (posthepatic-external jugular vein EJV; prehepatic-abdominal subcutaneous vein ASV and median caudal vein MCV) of dairy cows diagnosed with mastitis, ovarian cysts and pyometra. The presence of mycotoxins in the blood plasma was determined with the use of combined separation methods involving immunoaffinity columns, a liquid chromatography system and a mass spectrometry system. The parent compound was detected in all samples collected from diseased cows, whereas α-ZEL and ß-ZEL were not identified in any samples, or their concentrations were below the limit of detection (LOD). Zearalenone levels were highest in cows with pyometra, where the percentage share of average ZEN concentrations reached 44%. Blood sampling sites were arranged in the following ascending order based on ZEN concentrations: EJV (10.53 pg/mL, 44.07% of the samples collected from this site), ASV (14.20 pg/mL, 49.59% of the samples) and MCV (26.67 pg/mL, 67.35% of the samples). The results of the study indicate that blood samples for toxicological analyses should be collected from the MCV (prehepatic vessel) of clinically healthy cows and/or cows with subclinical ZEN mycotoxicosis. This sampling site increases the probability of correct diagnosis of subclinical ZEN mycotoxicosis.
Assuntos
Bovinos/sangue , Mastite Bovina/sangue , Micotoxicose/sangue , Cistos Ovarianos/sangue , Piometra/sangue , Zearalenona/sangue , Ração Animal , Animais , Monitoramento Biológico , Dieta/veterinária , Feminino , Contaminação de Alimentos , Micotoxicose/veterinária , Cistos Ovarianos/veterinária , Piometra/veterináriaRESUMO
The present study was designed to determine the efficacy of a novel multicomponent mycotoxin detoxifying agent (MMDA) containing modified zeolite (Clinoptilolite), Bacillus subtilis, B. licheniformis, Saccharomyces cerevisiae cell walls and silymarin against the deleterious effects of Aflatoxin B1 (AFB1) and Ochratoxin A (OTA) in broiler chicks. A total of 160 one-day-old Ross 308® broiler chicks were randomly allocated in four treatment groups, with four replicates, according to the following experimental design for 42 days. Group A received a basal diet; Group B received a basal diet contaminated with AFB1 and OTA at 0.1 mg/kg and 1 mg/kg, respectively; Group C received a basal diet contaminated with AFB1 and OTA and MMDA at 1 g/kg feed, and Group D received a basal diet contaminated with AFB1 and OTA and MMDA at 3 g/kg feed. Results showed that ingested mycotoxins led to significant (p ≤ 0.05) reduction in body weight and feed conversion from 25 days of age, induced histopathological changes, increased the pH of the intestinal content, and altered the biochemical profile of birds with significantly (p ≤ 0.05) increased aspartate aminotransferase (AST) values (p ≤ 0.05). On the other hand, the supplementation of MMDA significantly (p ≤ 0.05) improved the feed conversion ratio (FCR) during the second part of the study, diminished biochemical alterations, reduced pH in jejunal and ileal content, and E. coli counts in the caeca of birds (p ≤ 0.05). It may be concluded that the dietary supplementation of the MMDA partially ameliorated the adverse effects of AFB1 and OTA in broilers and could be an efficient tool in a mycotoxin control program.
Assuntos
Aflatoxina B1/envenenamento , Micotoxicose/tratamento farmacológico , Ocratoxinas/envenenamento , Silimarina/administração & dosagem , Zeolitas/administração & dosagem , Ração Animal , Animais , Bacillus licheniformis , Bacillus subtilis , Galinhas , Micotoxicose/metabolismo , Micotoxicose/patologia , Distribuição Aleatória , Saccharomyces cerevisiaeRESUMO
This experiment was conducted to investigate the effects of phytobiotic and antifungal feed additives on the growth performance, blood parameters, intestinal morphology, and cecal microbiota activity of broiler chickens under aflatoxicosis challenge. A total of 250 one-day-old Ross 308 broiler chicks (mixed sex) were reared on the littered floor with a completely randomized design by five treatments and five replicates for 35 days. Treatments included positive control (without AFB1), negative control-AFB1 (1 ppm), negative control-phytobiotic (Entex, 0.5 kg/t), negative control-Mycofix Plus (0.5 kg/t), and negative control-phytobiotic + Mycofix Plus. Dietary phytogenic and toxin binder improved body weight gain and feed conversion ratio of broiler chickens (p<0.05). Serum concentration of AST increased in broilers which received AFB1 without additives, while the blood concentration of total protein decreased (p<0.05). In jejuna morphometric indices, it was observed that the broiler chickens fed phytobiotic additive in combination with toxin binder had a greater villus length and crypt depth (p<0.05). Dietary treatments had no significant effect on the cecal microbial population in broiler chickens. In conclusion, the present results indicated that phytobiotic and toxin binder supplement improved growth performance and intestinal morphology of broiler chickens exposed to AFB1 challenge.
Assuntos
Galinhas , Micotoxicose , Aflatoxina B1/toxicidade , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais , Micotoxicose/veterináriaRESUMO
Since its first patent (1897), commercial dry feed (CDF) for dogs has diversified its formulation to meet the nutritional needs of different breeds, age, or special conditions and establish a foundation for integration of these pets into urban lifestyles. The risk of aflatoxicosis in dogs has increased because the ingredients used to formulate CDF have also proliferated, making it difficult to ensure the quality required of each to achieve the safety of the entire CDF. This review contains a description of the fungi and aflatoxins detected in CDF and the ingredients commonly used for their formulation. The mechanisms of action and pathogenic effects of aflatoxins are outlined; as well as the clinical findings, and macroscopic and microscopic lesions found in aflatoxicosis in dogs. In addition, alternatives for diagnosis, treatment, and control of aflatoxins (AF) in CDF are analyzed, such as biomarkers of effect, improvement of blood coagulation, rate of elimination of AF, control of secondary infection, protection of gastric mucosa, reduction of oxidative stress, use of chemo-protectors, sequestrants, grain-free CDF, biocontrol, and maximum permitted limits, are also included.
Assuntos
Aflatoxinas/toxicidade , Ração Animal/toxicidade , Contaminação de Alimentos , Doenças Transmitidas por Alimentos/veterinária , Micotoxicose/veterinária , Ração Animal/microbiologia , Animais , Doenças do Cão , Cães , Doenças Transmitidas por Alimentos/microbiologia , Fungos , Metabolismo SecundárioRESUMO
It is well known that T-2 toxin has cytotoxic radiomimetic like effects on the immune system. Because of scant research data demonstrating the chronic effects of low doses of the T-2 toxin on humoral and cellular responses in rats, the present experiment was undertaken. The animals were divided into four groups, namely, group I (0.5 ppm), group II (0.75 ppm) and group III (1.0 ppm) and group IV (control) were given toxin-free diet for 12 weeks and eight animals each were sacrificed at 2, 4, 6, 8, 10, and 12-week of the experimental period. The humoral immune response was evaluated based on hemagglutination test (HA), and levels of serum immunoglobulins (IgA, IgG, IgM) while the cell-mediated immune response was evaluated by delayed-type hypersensitivity (DTH) response to ovalbumin, lymphocyte stimulation index, analyses of CD4+ and CD8+ T lymphocytes and mRNA expression levels of selected cytokines like IL-2, IFN-γ, IL-4 and IL-10 by quantitative Real-time PCR in experimental groups. T-2 treatment caused suppression in both humoral and cell-mediated immune responses as evidenced by a decrease in all these parameters in toxin fed animals compared to the control in the dose and duration-dependent manner. This dose-dependent effect on the immune system has been further reflected largely by the depletion of lymphocytes from lymphoid organs as observed histopathologically in the spleen, thymus, and Peyer's patches in the present study.
Assuntos
Fusarium/química , Imunidade Humoral/efeitos dos fármacos , Imunoglobulina A/sangue , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Micotoxicose/fisiopatologia , Baço/efeitos dos fármacos , Toxina T-2/toxicidade , Animais , Relação Dose-Resposta a Droga , Humanos , Masculino , Ratos , Ratos WistarRESUMO
Aflatoxins (AFB1) are mycotoxins known to be associated with human and animal diseases. The lung is a at risk from AFB1exposure either via inhalation or circulation. Green tea consumption is increasing over time due to widespread popularity as antioxidants, anti-inflammatory, and cytoprotective agents. Therefore, we attempted to study the lung toxicity caused by AFB1 and the possible ameliorating effect of green tea extract. Forty adult male albino rats were divided into five groups; Group I: Untreated control group, Group II (vehicle): Each rat received 1 ml of olive oil, Group III (GTE): Each rat received Camellia sinensis, green tea extract (30 mg/kg/day), Group IV(AFB1): Each rat received (50 µg/kg/day of AFB1). Group V (AFB1+ GTE): Each rat received the same previously mentioned doses of AFB1 in addition to GTE concomitantly. All treatments were orally gavaged for 8 weeks then rats were sacrificed. Serum levels of pro-inflammatory (IL-1ß, TNF-α, IL-6) and anti-inflammatory (IL-10) cytokines were measured, lung tissues' oxidative stress indices were also measured in addition to the histopathological study which was performed by using hematoxylin & eosin and Masson trichrome stains. Morphometric and statistical analyses were also performed. Oral gavage of AFB1 resulted in significant histopathological changes in the lung tissues, in the form of variable degrees of congestion, hemorrhage, interstitial inflammation with infiltration by chronic inflammatory cells, interstitial fibrosis, bronchitis, vasculitis and fibrous thickening of arterial walls. Inflammation was evident by elevated levels of pro-inflammatory cytokines and a declined level of anti-inflammatory cytokines. Also, oxidative stress was evident by increased levels of Malondialdehyde (MDA), Myeloperoxidase (MPO), and decreased levels of total glutathione (tGSH) and Catalase (CAT). The histopathological changes, inflammatory cytokines, and oxidative stress markers were significantly decreased during concomitant administration of green tea extract in (AFB1+ GTE) group. Aflatoxin B1 has deleterious effects on the lung tissue that could be minimized by concomitant administration of Green tea extract owing to its anti-inflammatory, antioxidant, and protective properties.
Assuntos
Aflatoxina B1/toxicidade , Antioxidantes/farmacologia , Camellia sinensis , Extratos Vegetais/farmacologia , Chá , Animais , Anti-Inflamatórios , Biomarcadores , Citocinas , Glutationa , Inflamação , Fígado , Pulmão/fisiologia , Masculino , Malondialdeído , Micotoxicose , Estresse Oxidativo , RatosRESUMO
BACKGROUND: Heat stress and fescue toxicosis caused by ingesting tall fescue infected with the endophytic fungus Epichloë coenophiala represent two of the most prevalent stressors to beef cattle in the United States and cost the beef industry millions of dollars each year. The rate at which a beef cow sheds her winter coat early in the summer is an indicator of adaptation to heat and an economically relevant trait in temperate or subtropical parts of the world. Furthermore, research suggests that early-summer hair shedding may reflect tolerance to fescue toxicosis, since vasoconstriction induced by fescue toxicosis limits the ability of an animal to shed its winter coat. Both heat stress and fescue toxicosis reduce profitability partly via indirect maternal effects on calf weaning weight. Here, we developed parameters for routine genetic evaluation of hair shedding score in American Angus cattle, and identified genomic loci associated with variation in hair shedding score via genome-wide association analysis (GWAA). RESULTS: Hair shedding score was moderately heritable (h2 = 0.34 to 0.40), with different repeatability estimates between cattle grazing versus not grazing endophyte-infected tall fescue. Our results suggest modestly negative genetic and phenotypic correlations between a dam's hair shedding score (lower score is earlier shedding) and the weaning weight of her calf, which is one metric of performance. Together, these results indicate that economic gains can be made by using hair shedding score breeding values to select for heat-tolerant cattle. GWAA identified 176 variants significant at FDR < 0.05. Functional enrichment analyses using genes that were located within 50 kb of these variants identified pathways involved in keratin formation, prolactin signalling, host-virus interaction, and other biological processes. CONCLUSIONS: This work contributes to a continuing trend in the development of genetic evaluations for environmental adaptation. Our results will aid beef cattle producers in selecting more sustainable and climate-adapted cattle, as well as enable the development of similar routine genetic evaluations in other breeds.
Assuntos
Pelo Animal/fisiologia , Cruzamento/métodos , Bovinos/genética , Característica Quantitativa Herdável , Termotolerância/genética , Animais , Peso Corporal/genética , Bovinos/crescimento & desenvolvimento , Bovinos/fisiologia , Doenças dos Bovinos/genética , Doenças dos Bovinos/fisiopatologia , Suscetibilidade a Doenças , Epichloe , Queratinas/genética , Queratinas/metabolismo , Micotoxicose/genética , Micotoxicose/fisiopatologia , Micotoxicose/veterinária , Polimorfismo de Nucleotídeo Único , Prolactina/genética , Prolactina/metabolismo , DesmameRESUMO
This review focuses on factors associated with mold production in feedstuffs and major mycotoxins affecting ruminants in North America. Ruminants are often considered less sensitive to mycotoxins owing to rumen microflora metabolism to less toxic compounds. However, ruminants occupy wide agricultural niches that expose animals to diverse toxins under widely different environmental and nutritional conditions. Often the moldy and potentially highly contaminated feeds end up at feedlots. Less than optimal feedstuffs creating suboptimal rumen microbial flora could result in decreased ruminal capacity to detoxify certain mycotoxins and adverse effects. Numerous mycotoxins and clinical effects in ruminants are discussed.