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1.
Rev. bras. zootec ; 52: e20220155, 2023. tab
Artigo em Inglês | VETINDEX | ID: biblio-1436807

Resumo

The objective was to compare deoxynivalenol (DON) concentrations in feed ingredients and commercial swine diets measured by enzyme-linked immunosorbent assay (ELISA) and high-performance liquid chromatography (HPLC). Seventy feed ingredient samples consisted of corn, corn dried distillers grains with solubles, corn gluten feed, corn gluten meal, palm kernel expellers, rice bran, soy hulls, soybean meal, and wheat. Commercial swine diet samples (n = 92) were collected from 23 swine farms of varying regions in Korea and different growth stages of pigs. The DON concentration of all samples was determined in duplicate. Statistical comparisons were performed to compare the analytical methods (ELISA vs. HPLC), diet phases, and regions. The DON concentrations in most ingredients and all diets determined by ELISA method were greater than those determined by HPLC. The DON concentrations determined by the ELISA method were less than 1 mg/kg in all ingredients except corn dried distillers grains with solubles and corn gluten feed, and those determined by the HPLC were less than 0.5 mg/kg in all ingredients. The DON concentrations in complete diets did not vary by region or growth stages of pigs. The DON concentrations in most feed ingredients and commercial swine diets determined by ELISA method are greater than those determined by HPLC, but does not vary by regions in Republic of Korea or pig growth stages.


Assuntos
Animais , Suínos , Ensaio de Imunoadsorção Enzimática , Dieta/veterinária , Ração Animal , Micotoxinas
2.
Rev. Ciênc. Agrovet. (Online) ; 21(2): 176-181, mar. 2022. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1366279

Resumo

Mycotoxins pose a large threat to human and livestock besides reducing the quality of food/feed.It is believed that these toxins are biosynthesized as a mechanism of defense (stress-response) of fungi. The most important mycotoxin for winter-cereal crops is known by deoxynivalenol (DON), a trichothecene biosynthesized mainly by Fusarium graminearum. This manuscript brings data of three years (2018, 2019 and 2020) of field research (24 fieldexperiments) in Western Santa Catarina and North-Western Rio Grande do Sul, Brazil using a sulphated polysaccharide exclusive from red seaweed, carrageenan, associated with fungicides to help suppressing deoxynivalenol (DON) biosynthesis and accumulation in wheat kernels. A reduction of 36.4% in DON contamination was observed. Weather conditions have influenced the accumulation of DON in wheat kernels. Carrageenan has shown to be a biological compound capable of helping on the suppression of DON biosynthesis and accumulation in wheat kernels regardless of weather conditions.(AU)


As micotoxinas representam uma grande ameaça para humanos e animais, além de reduzirem a qualidade de alimentos/rações. Acredita-se que essas toxinas sejam biossintetizadas como mecanismo de defesa (resposta ao estresse) de fungos. A micotoxina de maior interesse para cereais de inverno é conhecida por desoxinivalenol (DON), um tricoteceno biossintetizado principalmente por Fusariumgraminearum. Esse estudo traz dados de três anos (2018, 2019 e 2020) de pesquisa de campo (24 experimentos) conduzidos no Oeste de Santa Catarina e no Nordeste do Rio Grande do Sul, Brasil,utilizando um polissacarídeo sulfatado exclusivo de algas vermelhas, carragena, associado a fungicidas para ajudar na supressão da biossíntese e acúmulo de desoxinivalenol (DON) em grãos de trigo. Foi observada uma redução de 36,4% na contaminação por DON. As condições climáticas influenciaram no acúmulo de DON nos grãos de trigo. A carragena se demostrou como um composto biológico capaz de atenuar a biossíntese e acúmulo de DON em grãos de trigo independente das condições climáticas.(AU)


Assuntos
Triticum/química , Imunossupressores/síntese química , Micotoxinas , Biossíntese de Proteínas , Fusarium
3.
Acta Vet. Brasilica ; 16(1): 31-35, jan. 2022. tab
Artigo em Inglês | VETINDEX | ID: biblio-1437465

Resumo

Circovirus is widespread in pig farming, and mainly affects piglets increasing morbidity and mortality rates, being vaccination the most effective strategy to control one. However, for an effective vaccine response, certain factors must be considered, such as the adoption of good practices during the conservation and handling of vaccines, environmental challenges, nutritional and health status of the animals, and presence of immunosuppressive agents, such as mycotoxins, in the feed. Here, we describe a circovirus outbreak associated with mycotoxin immunosuppression that occurred in the piglets during the nursery phase at a commercial farm, which initiated with a sudden increase in the mortality of vaccinated piglets. Blood samples were collected and analyzed using RT-PCR, while the feed was subjected to mycotoxicological analysis. RT-PCR analysis revealed the presence of porcine circovirus type 2 (PCV-2) in the blood serum samples, thereby confirming the circovirus outbreak. The feed analysis revealed elevated levels of mycotoxins (deoxynivalenol, aflatoxins, and fumonisins), which were above the levels tolerated by the piglets during the nursery phase. Therefore, the contaminated feed was discarded, and a new ration was made available. Concurrently, the vaccination program was amended to normalize the mortality rate. The presence of mycotoxins in the feed could be the predisposed factor for piglet infection caused by PCV-2 and other diseases. This is an important aspect because the immunosuppressive effect of mycotoxins can alter the vaccine response, thereby making the piglets more susceptible to the diseases even after being vaccinated, although they should be immunologically protected.(AU)


O circovírus é muito difundido na suinocultura e atinge principalmente leitões, aumentando as taxas de morbi-mortalidade, sendo a vacinação a estratégia mais eficaz de controle. No entanto, para uma resposta vacinal eficaz, alguns fato-res devem ser considerados, como a adoção de boas práticas durante a conservação e manuseio de vacinas, desafios ambientais, estado nutricional e de saúde dos animais e presença de agentes imunossupressores, como micotoxinas, na ração. Descreveu-se um surto de circovírus associado à imunossupressão por micotoxinas que ocorreu em leitões durante a fase de creche em uma granja comercial, que começou com um aumento repentino na mortalidade de leitões vacinados. Amostras de sangue foram coletadas e analisadas por RT-PCR, enquanto a ração foi submetida à análise micotoxicológica. A análise de RT-PCR revelou a presença de circovírus suíno tipo 2 (PCV-2), confirmando assim o surto de circovírus. A análise da ração revelou níveis de micotoxinas (desoxinivalenol, aflatoxinas e fumonisinas) acima dos tolerados pelos leitões nesta fase. Portanto, o alimento con-taminado foi descartado e uma nova ração foi disponibilizada. Simultaneamente, o programa de vacinação foi alterado para normalizar a taxa de mortalidade. A presença de micotoxinas na ração pode ser o fator predisponente para infecção de leitões causada por PCV-2 e outras doenças. Esse é um aspecto importante, pois o efeito imunossupressor das micotoxinas pode alte-rar a resposta vacinal, tornando os leitões mais suscetíveis às doenças mesmo após vacinação.(AU)


Assuntos
Animais , Suínos/virologia , Micotoxicose/veterinária , Infecções por Circoviridae/diagnóstico , Circoviridae/patogenicidade
4.
Acta Vet. Brasilica ; 16(2): 126-133, maio 2022. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1392537

Resumo

As mycotoxins are consistent contaminants in the dairy cow diet, the use of adsorbents is recommended, although there are no ideal adsorbents. Although there are studies on this subject, few have focused on chronic natural intoxications. Here, we evaluated the effect of bentonite adsorbents associated with liver antioxidants on the health and milk production of dairy cows fed a diet containing naturally-produced fumonisin, zearalenone, and deoxynivalenol. Eighteen dairy cows (bodyweight 550 ±50 kg, 5 ± 2 years old, and 30 ± 1,25 kg/day milk production) in the middle of lactation were divided into groups: treatment (TG, n = 9, 22 g/day of supplement added to diet) and control (CG, n = 9, without supplement). A physical examination was performed, weekly over 56 days and blood was collected for liver and immune assessments. Milk was harvested to evaluate milk production and content (fat protein, somatic cell count, and lactose). The additive promoted beneficial effects on the liver from the 24th day due to a decrease in the enzymatic activities of gamma-glutamyltransferase and lactate dehydrogenase and increased serum protein and albumin levels. There were improvements in health, evidenced as fewer clinical manifestations of the disease, greater leukocyte oxidative metabolism capacity, and a lower neutrophil lymphocytes ratio. The treatment also promoted a 19% increase in milk volume. It was concluded that the additive promoted health benefits and milk production in dairy cows.(AU)


Como as micotoxinas são contaminantes constantes na dieta de vacas leiteiras, o uso de adsorventes é recomendado, embora não existam adsorventes ideiais. Ainda que existam estudos sobre o assunto, poucos são direcionados às intoxicações naturais crônicas. Nosso experimento avaliou o efeito do adsorvente bentonita associado a antioxidantes hepáticos sobre a saúde e produção de leite de vacas leiteiras alimentadas com dieta contendo fumonisina, zearalenona e desoxinivalenol produzidos naturalmente. Dezoito vacas lei-teiras (peso corporal 550 ±50 kg, 5±2 anos de idade, e 30 ± 1,25 kg/dia de produção de leite) no meio da lactação, foram divididas em grupos: Tratamento (GT, n=9, 22g/dia do suplemento adicionado à dieta) e controle (GC, n =9, sem suplemento). Em intervalos semanais, durante 56 dias, foi realizado exame físico, coleta de sangue para avaliação hepática e imunológica. O leite foi colhido para avaliar a produção e análises de leite para (proteína, gordura, contagem de células somáticas e lactose). O aditivo promoveu efeitos bené-ficos no fígado à partir do 24º dia devido à diminuição das atividades enzimáticas da gama-glutamiltransferase e lactato desidrogenase e aumento dos níveis séricos de proteína e albumina. Houve melhora na saúde, evidenciada por menor número de manifestações clínicas de doença, maior capacidade de metabolismo oxidativo dos leucócitos e menor razão neutrófilos/linfócitos. O tratamento também promo-veu aumento de 19% no volume de leite. Concluiu-se que o aditivo promoveu benefícios à saúde e à produção de leite em vacas leiteiras.(AU)


Assuntos
Animais , Feminino , Bentonita/efeitos adversos , Bovinos/fisiologia , Micotoxinas/efeitos adversos , Antioxidantes/efeitos adversos , Ração Animal/análise
5.
Sci. agric ; 77(3): e20180236, 2020. ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1497851

Resumo

The effects of mycotoxins on the productive performance of growing pigs and broilers were evaluated using meta-analytical approach. Two databases were constructed: (1) Broilers, with information collected from 51,497 birds and published in 158 scientific papers from 1980 to 2016; and (2) Pigs, with information collected from 7,743 animals and published in 72 scientific papers from 1980 to 2015. The meta-analyses were performed independently for each specie, following three sequential analyses: graphical, correlation, and variance-covariance. Broilers and pigs challenged by mycotoxins reduced (p < 0.05) feed intake by 9 and 6 %, weight gain by 15 and 11 %, and feed efficiency by 6 and 4 % compared with non-challenged animals, respectively. Aflatoxins were the most studied mycotoxins in both databases. Birds and pigs challenged by aflatoxins reduced (p < 0.05) feed intake by 10 and 8 %, growth by 15 and 11 %, and feed efficiency by 6 and 7 % compared to non-challenged animals, respectively. In both databases, variation on growth performance due to mycotoxins showed a linear relationship (p < 0.05) with the feed intake variation caused by the challenge. The intercepts of the regression-based equations were different from zero and negative, which may indicate that mycotoxins altered the maintenance requirements in challenged animals. In conclusion, both broilers and growing pigs show losses in performance responses and worse nutritional efficiency when challenged by mycotoxins.


Assuntos
Animais , Aflatoxinas , Galinhas/crescimento & desenvolvimento , Galinhas/imunologia , Galinhas/microbiologia , Ração Animal/microbiologia , Sus scrofa/crescimento & desenvolvimento , Sus scrofa/imunologia , Sus scrofa/microbiologia , Dieta/veterinária
6.
Sci. agric. ; 77(3): e20180236, 2020. ilus, tab
Artigo em Inglês | VETINDEX | ID: vti-24969

Resumo

The effects of mycotoxins on the productive performance of growing pigs and broilers were evaluated using meta-analytical approach. Two databases were constructed: (1) Broilers, with information collected from 51,497 birds and published in 158 scientific papers from 1980 to 2016; and (2) Pigs, with information collected from 7,743 animals and published in 72 scientific papers from 1980 to 2015. The meta-analyses were performed independently for each specie, following three sequential analyses: graphical, correlation, and variance-covariance. Broilers and pigs challenged by mycotoxins reduced (p < 0.05) feed intake by 9 and 6 %, weight gain by 15 and 11 %, and feed efficiency by 6 and 4 % compared with non-challenged animals, respectively. Aflatoxins were the most studied mycotoxins in both databases. Birds and pigs challenged by aflatoxins reduced (p < 0.05) feed intake by 10 and 8 %, growth by 15 and 11 %, and feed efficiency by 6 and 7 % compared to non-challenged animals, respectively. In both databases, variation on growth performance due to mycotoxins showed a linear relationship (p < 0.05) with the feed intake variation caused by the challenge. The intercepts of the regression-based equations were different from zero and negative, which may indicate that mycotoxins altered the maintenance requirements in challenged animals. In conclusion, both broilers and growing pigs show losses in performance responses and worse nutritional efficiency when challenged by mycotoxins.(AU)


Assuntos
Animais , Galinhas/imunologia , Sus scrofa/imunologia , Aflatoxinas , Galinhas/crescimento & desenvolvimento , Galinhas/microbiologia , Sus scrofa/crescimento & desenvolvimento , Sus scrofa/microbiologia , Ração Animal/microbiologia , Dieta/veterinária
7.
Ci. Rural ; 49(11): e20190271, 2019. tab
Artigo em Inglês | VETINDEX | ID: vti-24457

Resumo

Purple maize is an important foodstuff for the Peruvian people. Its unique nutritional and antioxidant characteristics makes it widely exported to other countries. However, when contaminated by fungi, it can trigger numerous health problems in the consumers. This study aimed to evaluate the presence of 27 mycotoxins in 63 samples of purple maize collected in Peru. Frequency of occurrence and mean concentration of the following mycotoxins were determined: alternariolmetileter (AME), alternariol (AOH), tentoxin, neosolaniol, nivalenol, wortmannin, deoxynivalenol, 3-acetyl deoxynivalenol, 15-acetyl deoxynivalenol, zearalenone, aflatoxin B1, aflatoxin B2, aflatoxin G1, aflatoxin G2, fumonisin B1, fumonisin B2, fumonisin B3, ochratoxin A, ochratoxin , T-2 toxin, HT-2 toxin, fusarenon x, cyclopiazonic acid, gliotoxin, agroclavin and citreoviridin. The main mycotoxins reported in purple maize were AME and AOH, with a frequency of occurrence of 14.3 and 7.9%, and mean concentration of 23.3% and 1.8%, respectively. AME and AOH do not have guidance levels in the Brazilian legislation. Contrastingly, levels of mycotoxins which are within the standards of the countrys regulations were below the limit of quantification. The present results suggested that purple maize is a raw material with a great potential for the production and industrialization of special products.(AU)


O milho roxo é um alimento importante para o povo peruano. Suas características nutricionais e antioxidantes únicas fazem com que seja amplamente exportado para outros países. No entanto, quando contaminado por fungos, pode desencadear inúmeros problemas de saúde nos consumidores. Este estudo teve como objetivo avaliar a presença de 27 micotoxinas em 63 amostras de milho roxo coletadas no Peru. A frequência de ocorrência e a concentração média das seguintes micotoxinas foram determinadas: alternariolmetileter (AME), alternariol (AOH), tentoxina, neosolaniol, nivalenol, wortmanina, desoxinivalenol, 3-acetil desoxinivalenol, 15-acetil desoxinivalenol, zearalenona, aflatoxina B1, aflatoxina B2 , aflatoxina G1, aflatoxina G2, fumonisina B1, fumonisina B2, fumonisina B3, ocratoxina A, ocratoxina, toxina T-2, toxina HT-2, fusarenona x, ácido ciclopiazonico, gliotoxina, agroclavina e citreoviridina. As principais micotoxinas encontradas no milho roxo foram AME e AOH, com frequência de ocorrência de 14,3% e 7,9% e concentração média de 23,3% e 1,8%, respectivamente. AME e AOH não possuem níveis de orientação na legislação brasileira. Contrastantemente, os níveis de micotoxinas que estão dentro dos padrões das regulamentações do país estavam abaixo do limite de quantificação. Os presentes resultados sugerem que o milho roxo é uma matéria-prima com grande potencial para a produção e industrialização de produtos especiais.(AU)


Assuntos
Zea mays/fisiologia , Zea mays/toxicidade , Micotoxinas
8.
Arq. bras. med. vet. zootec. (Online) ; 71(5): 1659-1668, set.-out. 2019. tab, graf
Artigo em Português | LILACS, VETINDEX | ID: biblio-1038665

Resumo

Objetivou-se avaliar as variáveis micotoxicológicas e nutricionais de híbridos de milho com diferentes características que influenciam no custo da ração para frangos de corte. Foram avaliados 26 híbridos de milho geneticamente modificados nas safrinhas de 2016 e 2017, com diferentes germoplasmas, textura de endosperma e duração do ciclo. Nos híbridos, foram avaliados grãos avariados, fumonisinas (B1+B2) (FUM), aflatoxinas (B1+B2+G1+G2) (AFLA), zearalenona (ZEA), deoxinivalenol (DON), umidade, proteína bruta (PB), energia metabolizável aparente corrigida para balanço de nitrogênio (EMAn), aminoácidos digestíveis para aves (lisina, metionina, cistina e treonina) e o respectivo custo da ração inicial para frangos de corte, que foi calculada pelo custo mínimo. A prevalência de FUM, AFLA, ZEA e DON foi de 90, 17, 33 e 0%, com médias de 3067, 1, 38 e 0µg/kg nos dois anos, respectivamente. A média de EMAn e PB foi de 3264kcal/kg e 8,02%, respectivamente, e diferiu (P<0,05) nos dois anos. O custo da ração foi influenciado significativamente (P<0,05) por FUM, PB, EMAn nos dois anos. Híbridos com tecnologia Viptera apresentam menor concentração por FUM e menor custo da ração. Híbridos de ciclo precoce têm menor concentração de FUM, maiores percentuais de PB e de aminoácidos digestíveis e menor custo da ração.(AU)


The objective of this study was to evaluate the mycotoxicological and nutritional variables of maize hybrids with different characteristics that influence the broiler chicken's feed costs. In 2016 and 2017 winter crops, 26 genetically modified hybrids of maize with different germplasm, endosperm texture and cycle duration were evaluated. The analyzed variables were damaged grains, fumonisins (B 1 +B 2 ) (FUM), aflatoxins (B 1 +B 2 +G 1 +G 2 ) (AFLA), zearalenone (ZEA), deoxynivalenol (DON), moisture, crude protein (CP), apparent metabolizable energy corrected for nitrogen balance (AMEn), digestible amino acids for poultry (lysine, methionine, cystine and threonine) and the respective cost of the initial feed for broiler chickens calculated at the minimum cost. The prevalence of FUM, AFLA, ZEA and DON was 90, 17, 33 and 0%, with means of 3067, 1, 38 and 0µg/kg in the two years, respectively. The mean of AMEn and CP was 3264kcal/kg and 8.02%, respectively, and differed (P< 0.05) in the two years. The feed cost was significantly influenced (P<0.05) by FUM, PB, AMEn in two years. Hybrids with Viptera technology show lower concentration per FUM and lower feed cost. Early cycle hybrids have lower concentrations of FUM, higher percentages of CP and digestible amino acids, and lower feed costs.(AU)


Assuntos
Zea mays/genética , Zea mays/toxicidade , Ração Animal/toxicidade , Micotoxinas/análise , Micotoxinas/toxicidade , Zearalenona/toxicidade , Aflatoxinas/toxicidade , Fumonisinas/toxicidade
9.
Arq. bras. med. vet. zootec. (Online) ; 71(5): 1659-1668, set.-out. 2019. tab, graf
Artigo em Português | VETINDEX | ID: vti-25284

Resumo

Objetivou-se avaliar as variáveis micotoxicológicas e nutricionais de híbridos de milho com diferentes características que influenciam no custo da ração para frangos de corte. Foram avaliados 26 híbridos de milho geneticamente modificados nas safrinhas de 2016 e 2017, com diferentes germoplasmas, textura de endosperma e duração do ciclo. Nos híbridos, foram avaliados grãos avariados, fumonisinas (B1+B2) (FUM), aflatoxinas (B1+B2+G1+G2) (AFLA), zearalenona (ZEA), deoxinivalenol (DON), umidade, proteína bruta (PB), energia metabolizável aparente corrigida para balanço de nitrogênio (EMAn), aminoácidos digestíveis para aves (lisina, metionina, cistina e treonina) e o respectivo custo da ração inicial para frangos de corte, que foi calculada pelo custo mínimo. A prevalência de FUM, AFLA, ZEA e DON foi de 90, 17, 33 e 0%, com médias de 3067, 1, 38 e 0µg/kg nos dois anos, respectivamente. A média de EMAn e PB foi de 3264kcal/kg e 8,02%, respectivamente, e diferiu (P<0,05) nos dois anos. O custo da ração foi influenciado significativamente (P<0,05) por FUM, PB, EMAn nos dois anos. Híbridos com tecnologia Viptera apresentam menor concentração por FUM e menor custo da ração. Híbridos de ciclo precoce têm menor concentração de FUM, maiores percentuais de PB e de aminoácidos digestíveis e menor custo da ração.(AU)


The objective of this study was to evaluate the mycotoxicological and nutritional variables of maize hybrids with different characteristics that influence the broiler chicken's feed costs. In 2016 and 2017 winter crops, 26 genetically modified hybrids of maize with different germplasm, endosperm texture and cycle duration were evaluated. The analyzed variables were damaged grains, fumonisins (B 1 +B 2 ) (FUM), aflatoxins (B 1 +B 2 +G 1 +G 2 ) (AFLA), zearalenone (ZEA), deoxynivalenol (DON), moisture, crude protein (CP), apparent metabolizable energy corrected for nitrogen balance (AMEn), digestible amino acids for poultry (lysine, methionine, cystine and threonine) and the respective cost of the initial feed for broiler chickens calculated at the minimum cost. The prevalence of FUM, AFLA, ZEA and DON was 90, 17, 33 and 0%, with means of 3067, 1, 38 and 0µg/kg in the two years, respectively. The mean of AMEn and CP was 3264kcal/kg and 8.02%, respectively, and differed (P< 0.05) in the two years. The feed cost was significantly influenced (P<0.05) by FUM, PB, AMEn in two years. Hybrids with Viptera technology show lower concentration per FUM and lower feed cost. Early cycle hybrids have lower concentrations of FUM, higher percentages of CP and digestible amino acids, and lower feed costs.(AU)


Assuntos
Zea mays/genética , Zea mays/toxicidade , Ração Animal/toxicidade , Micotoxinas/análise , Micotoxinas/toxicidade , Zearalenona/toxicidade , Aflatoxinas/toxicidade , Fumonisinas/toxicidade
10.
Sci. agric ; 75(5): 426-431, Sept.-Oct.2018. tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1497736

Resumo

Mycotoxin levels in Fusarium head blight (FHB) infections can be difficult to quantify. The relationship between mycotoxin and disease is not consistent and it is not clear if wheat-pathogen interaction is of significance in regions where more than one Fusarium species with dis-tinct trichothecene production ability co-exists. This study aimed to investigate whether a set of eight Brazilian wheat genotypes, varying in resistance according to classification by the breeder, exhibit a common or differential resistance to Fusarium graminearum (Fgra) (deoxynivalenol-producing) and Fusarium meridionale (nivalenol-producing) (Fmer) using full-spike and central spikelet inoculation (type II resistance). Fgra was generally more aggressive than Fmer based on the percentage of diseased spikes (99 and 84 %, respectively) and number of diseased spikelets (mean 2.8 and 2.0, respectively) below the central spikelet. The genotype-pathogen species interaction was not significant, but there were differences between the genotypes, with BRS 194 and BRS 327 being the least and most resistant, respectively, based on severity ratings. The incidence of Fusarium-damaged kernel (FDK, %) was not affected by species, but two genotypes (BRS Parrudo and BRS 327) showed a lower incidence of FDK. There were substantial variations in the accumulation of deoxynivalenol and nivalenol among the genotypes, reaching maxima of 691.2 μg g–1 and 355.2 μg g–1, respectively, suggesting that Fgra is a more potent producer of trichothecene. Our data confirm prior resistance classifications by the breeders and suggest that the use of a single highly aggressive Fgra isolate may be sufficient for effective screening for FHB resistance. However, further studies are needed to elucidate the accumulation of resistance to trichothecene.


Assuntos
Fusarium , Micotoxinas , Triticum , Farmacorresistência Fúngica
11.
Sci. agric. ; 75(5): 426-431, Sept.-Oct.2018. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-731208

Resumo

Mycotoxin levels in Fusarium head blight (FHB) infections can be difficult to quantify. The relationship between mycotoxin and disease is not consistent and it is not clear if wheat-pathogen interaction is of significance in regions where more than one Fusarium species with dis-tinct trichothecene production ability co-exists. This study aimed to investigate whether a set of eight Brazilian wheat genotypes, varying in resistance according to classification by the breeder, exhibit a common or differential resistance to Fusarium graminearum (Fgra) (deoxynivalenol-producing) and Fusarium meridionale (nivalenol-producing) (Fmer) using full-spike and central spikelet inoculation (type II resistance). Fgra was generally more aggressive than Fmer based on the percentage of diseased spikes (99 and 84 %, respectively) and number of diseased spikelets (mean 2.8 and 2.0, respectively) below the central spikelet. The genotype-pathogen species interaction was not significant, but there were differences between the genotypes, with BRS 194 and BRS 327 being the least and most resistant, respectively, based on severity ratings. The incidence of Fusarium-damaged kernel (FDK, %) was not affected by species, but two genotypes (BRS Parrudo and BRS 327) showed a lower incidence of FDK. There were substantial variations in the accumulation of deoxynivalenol and nivalenol among the genotypes, reaching maxima of 691.2 μg g–1 and 355.2 μg g–1, respectively, suggesting that Fgra is a more potent producer of trichothecene. Our data confirm prior resistance classifications by the breeders and suggest that the use of a single highly aggressive Fgra isolate may be sufficient for effective screening for FHB resistance. However, further studies are needed to elucidate the accumulation of resistance to trichothecene.(AU)


Assuntos
Fusarium , Micotoxinas , Triticum , Farmacorresistência Fúngica
12.
Rev. Ciênc. Agrovet. (Online) ; 17(2): 292-299, 2018.
Artigo em Inglês | VETINDEX | ID: biblio-1488235

Resumo

The occurrence of mycotoxins has become a problem to be discussed, due to its harmfulness to humans and animals health, and may be an obstacle to the poultry economy. Mycotoxins are toxic metabolites produced by certain species of fungi and may contaminate food. Aflatoxins are mainly produced by Aspergillus flavus and Aspergillus parasiticus, and B1, B2, G1 and G2 are its best known types. Fumonisin, with its B1, B2 or B3 types, are produced by Fusarium, while ochratoxin A is produced by Penicillium and Aspergillus. The main trichothecenes mycotoxins are T-2 toxin, deoxynivalenol and diacetoxyscirpenol. Zearalenone, produced by different species of Fusarium fungi affects chickens only when they are exposed to extremely high levels of contamination. Generally, immunosuppression, hepatotoxicity and nephrotoxicity as a decrease in performance and production gains are the most observed effects. There are several laboratory methods that can be used for the determination of mycotoxins. In order to control the contamination, it is necessary to adopt proper farming practices which prevent fungi growth. Once grains and feed are contaminated, biological, physical and/or chemical decontamination methods may be employed, although the physical process with adsorbents mixed to the feed is more widely used. Due to the importance of mycotoxins to poultry production, it is necessary to adopt measures to prevent contamination, and also develop a control and an anti-fungal growth and toxin production program by reviewing the critical points favorable to the emergence of toxin-producing fungi.


A ocorrência de micotoxinas tornou-se um problema a ser discutido, pois representa riscos à saúde dos animais e humanos, podendo constituir um obstáculo à economia avícola. Micotoxinas são metabólitos tóxicos produzidos por algumas espécies de fungos e podem contaminar os alimentos. Aflatoxinas são majoritariamente produzidas por Aspergillus flavus e Aspergillus parasiticus, sendo B1, B2, G1 e G2 os tipos mais conhecidos. Fumonisinas são do tipo B1, B2 e B3, e produzidas pelo gênero Fusarium, enquanto a ocratoxina A é produzida por fungos da espécie Penicillium e Aspergillus. As principais micotoxinas dos tricotecenos são toxina T-2, deoxynivalenol e diacetoxyscirpenol. A zearalenona, produzida por diferentes espécies de fungos do gênero Fusarium, afeta os frangos apenas quando estes são expostos a níveis extremamente altos de contaminação. De modo geral, são observados efeitos imunossupressores, hepatotóxicos e nefrotóxicos, com queda no desempenho e nos ganhos de produção. Vários são os métodos laboratoriais que podem ser utilizados para a determinação de micotoxinas. Para o controle da contaminação, é necessário adoção de práticas agrícolas correta, com vistas à prevenção do crescimento de fungos. Após a contaminação de grãos e rações, métodos de descontaminação, biológicos, físicos e/ou químicos podem ser empregados, embora o processo físico com adsorventes misturados às rações seja o mais utilizado. Pela importância que as micotoxinas representam à produção de frangos, é necessário adotar medidas que previnam a contaminação e desenvolver programas de controle e combate ao desenvolvimento fúngico e produção de toxinas, revendo os pontos críticos propícios ao aparecimento dos fungos geradores das toxinas.


Assuntos
Animais , Aflatoxinas/análise , Fumonisinas/análise , Galinhas/microbiologia , Ocratoxinas/análise , Tricotecenos/análise , Zearalenona/análise , Aves Domésticas/microbiologia , Micotoxinas/análise , Ração Animal/toxicidade
13.
R. Ci. agrovet. ; 17(2): 292-299, 2018.
Artigo em Inglês | VETINDEX | ID: vti-734632

Resumo

The occurrence of mycotoxins has become a problem to be discussed, due to its harmfulness to humans and animals health, and may be an obstacle to the poultry economy. Mycotoxins are toxic metabolites produced by certain species of fungi and may contaminate food. Aflatoxins are mainly produced by Aspergillus flavus and Aspergillus parasiticus, and B1, B2, G1 and G2 are its best known types. Fumonisin, with its B1, B2 or B3 types, are produced by Fusarium, while ochratoxin A is produced by Penicillium and Aspergillus. The main trichothecenes mycotoxins are T-2 toxin, deoxynivalenol and diacetoxyscirpenol. Zearalenone, produced by different species of Fusarium fungi affects chickens only when they are exposed to extremely high levels of contamination. Generally, immunosuppression, hepatotoxicity and nephrotoxicity as a decrease in performance and production gains are the most observed effects. There are several laboratory methods that can be used for the determination of mycotoxins. In order to control the contamination, it is necessary to adopt proper farming practices which prevent fungi growth. Once grains and feed are contaminated, biological, physical and/or chemical decontamination methods may be employed, although the physical process with adsorbents mixed to the feed is more widely used. Due to the importance of mycotoxins to poultry production, it is necessary to adopt measures to prevent contamination, and also develop a control and an anti-fungal growth and toxin production program by reviewing the critical points favorable to the emergence of toxin-producing fungi.(AU)


A ocorrência de micotoxinas tornou-se um problema a ser discutido, pois representa riscos à saúde dos animais e humanos, podendo constituir um obstáculo à economia avícola. Micotoxinas são metabólitos tóxicos produzidos por algumas espécies de fungos e podem contaminar os alimentos. Aflatoxinas são majoritariamente produzidas por Aspergillus flavus e Aspergillus parasiticus, sendo B1, B2, G1 e G2 os tipos mais conhecidos. Fumonisinas são do tipo B1, B2 e B3, e produzidas pelo gênero Fusarium, enquanto a ocratoxina A é produzida por fungos da espécie Penicillium e Aspergillus. As principais micotoxinas dos tricotecenos são toxina T-2, deoxynivalenol e diacetoxyscirpenol. A zearalenona, produzida por diferentes espécies de fungos do gênero Fusarium, afeta os frangos apenas quando estes são expostos a níveis extremamente altos de contaminação. De modo geral, são observados efeitos imunossupressores, hepatotóxicos e nefrotóxicos, com queda no desempenho e nos ganhos de produção. Vários são os métodos laboratoriais que podem ser utilizados para a determinação de micotoxinas. Para o controle da contaminação, é necessário adoção de práticas agrícolas correta, com vistas à prevenção do crescimento de fungos. Após a contaminação de grãos e rações, métodos de descontaminação, biológicos, físicos e/ou químicos podem ser empregados, embora o processo físico com adsorventes misturados às rações seja o mais utilizado. Pela importância que as micotoxinas representam à produção de frangos, é necessário adotar medidas que previnam a contaminação e desenvolver programas de controle e combate ao desenvolvimento fúngico e produção de toxinas, revendo os pontos críticos propícios ao aparecimento dos fungos geradores das toxinas.(AU)


Assuntos
Animais , Galinhas/microbiologia , Aflatoxinas/análise , Fumonisinas/análise , Ocratoxinas/análise , Tricotecenos/análise , Zearalenona/análise , Micotoxinas/análise , Ração Animal/toxicidade , Aves Domésticas/microbiologia
14.
Sci. agric ; 74(4): 343-348, Aug. 2017. ilus
Artigo em Inglês | VETINDEX | ID: biblio-1497646

Resumo

One hundred commercial wheat grain samples were collected during the 2015 sea-son across 78 municipalities in the states of Paraná (PR), Rio Grande do Sul (RS), and São Paulo (SP), Brazil. Separate subsamples were analyzed for the concentration of deoxynivalenol (DON), zearalenona (ZEA) and ochratoxin A (OTA) mycotoxins using two methods: UHPLC-MS/MS (reference method) and a commercial enzyme-linked immunosorbent assay (ELISA) (AgraQuant®). The OTA mycotoxin was not found in the samples by both methods. DON and ZEA were detected in 55 % and 39 % of the samples by the reference method, with overall mean levels of 795.2 g kg1 and 79.78 g kg1, respectively. There was a significant and positive correlation (Spearman rank) between DON and ZEA estimates by the reference method (r = 0.77, p 0.001). The DON levels estimated by the immunoassay agreed poorly with the reference, being largely overestimated. Based on a cut-off level of 1000 g kg1, the immunoassay correctly classified 57 samples as true negatives and 15 as true positives. Only 28 were classified as false positives. For ZEA, the levels estimated by the two methods were in better agreement than for DON. Using the cut-off level of 200 g kg1, 96 % of the samples were classified correctly as true positives and only one sample was classified as false positive. The levels for both mycotoxins were mostly acceptable for human consumption. Further studies should focus on multi-toxin methods compared with immunoassays to understand the reasons of overestimation and the role of immunoassays as a cost-effective solution for fast screening of mycotoxins in the food chain.


Assuntos
Cromatografia Líquida , Ensaio de Imunoadsorção Enzimática , Ocratoxinas/análise , Tricotecenos/análise , Triticum , Imunoensaio/métodos , Micotoxinas/análise , Produtos Agrícolas
15.
Sci. agric. ; 74(4): 343-348, Aug. 2017. ilus
Artigo em Inglês | VETINDEX | ID: vti-716818

Resumo

One hundred commercial wheat grain samples were collected during the 2015 sea-son across 78 municipalities in the states of Paraná (PR), Rio Grande do Sul (RS), and São Paulo (SP), Brazil. Separate subsamples were analyzed for the concentration of deoxynivalenol (DON), zearalenona (ZEA) and ochratoxin A (OTA) mycotoxins using two methods: UHPLC-MS/MS (reference method) and a commercial enzyme-linked immunosorbent assay (ELISA) (AgraQuant®). The OTA mycotoxin was not found in the samples by both methods. DON and ZEA were detected in 55 % and 39 % of the samples by the reference method, with overall mean levels of 795.2 g kg1 and 79.78 g kg1, respectively. There was a significant and positive correlation (Spearman rank) between DON and ZEA estimates by the reference method (r = 0.77, p 0.001). The DON levels estimated by the immunoassay agreed poorly with the reference, being largely overestimated. Based on a cut-off level of 1000 g kg1, the immunoassay correctly classified 57 samples as true negatives and 15 as true positives. Only 28 were classified as false positives. For ZEA, the levels estimated by the two methods were in better agreement than for DON. Using the cut-off level of 200 g kg1, 96 % of the samples were classified correctly as true positives and only one sample was classified as false positive. The levels for both mycotoxins were mostly acceptable for human consumption. Further studies should focus on multi-toxin methods compared with immunoassays to understand the reasons of overestimation and the role of immunoassays as a cost-effective solution for fast screening of mycotoxins in the food chain.(AU)


Assuntos
Ensaio de Imunoadsorção Enzimática , Cromatografia Líquida , Tricotecenos/análise , Ocratoxinas/análise , Triticum , Micotoxinas/análise , Imunoensaio/métodos , Produtos Agrícolas
16.
Arq. bras. med. vet. zootec ; 69(2): 269-277, mar.-abr. 2017. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-833807

Resumo

The aim of the current study was to investigate biogenic amines and mycotoxins concentrations in baled silage (mainly Poaceae family grasses) prepared in organic and conventional farms and to relate these parameters to fermentative parameters. The mean dry matter (DM) content was 364.10±93.31 and 424.70±95.93g/kg in the silage from organic and conventional farms respectively. The silage samples from organic farms had 17.00% higher (P≤ 0.05) tyramine (TY) than the silage from conventional farms. Conventional farm samples were characterized by 46.00% higher histamine (HIS) (P≤ 0.05), 9.80% higher putrescine (PUT) (P≤ 0.05), 17.30% higher cadaverine (CAD) (P≤ 0.05). Aflatoxins (AFL) (total) and zearalenone (ZEN), T-2/HT-2 concentrations were higher respectively 16.00% (P≤ 0.05) and 13.40% (P≤ 0.05), 1.80% (P≤ 0.05) in the silage prepared in organic farms. Deoxynivalenol (DON) concentration was higher 42.40% (P≤ 0.05) in silage from conventional farms. Volatile fatty acids (VFA), lactic acid, ethanol, pH and ammonia nitrogen showed that the silage samples from organic and conventional farms were of good quality. Our study suggests differences in biogenic amine formation or mycotoxins content in silage from organic and conventional farming, but, overall, the measured values are too low to be relevant for animal health. Furthermore, these differences might as well be due to the difference in dry matter content and plant maturity between the organic and conventional silage samples.(AU)


O objetivo do presente estudo foi investigar concentrações de aminas biogênicas micotoxinas em silagem embalada (principalmente gramíneas da família Poaceae) preparada em fazendas orgânicas e convencionais e relacionar esses parâmetros a parâmetros fermentativos. A massa seca média (MS) foi 364,10±93,31 e 424,70±95,93g/kg na silagem de fazendas orgânicas e convencionais, respectivamente. As amostras de silagem de fazendas orgânicas tinham 17% a mais de tyramina (TY) (p≤ 0,05) que as de fazendas convencionais. As amostras de fazendas convencionais foram caracterizadas por histamina (HIS) 46,00% mais alta (P≤ 0,05), 9,80% putrecina (PUT) mais alta (P≤ 0,05), 17,30% de cadaverina (CAD) mais alta (P≤ 0,05). Aflatoxnas (AFL) (total) e zearalenone (ZEN), T-2/HT-2 tinham concentrações mais altas em respectivamente 16,00% (P≤ 0,05) e 13,40% (P≤ 0,05), 1,80% (P≤ 0,05) na silagem preparada em fazendas orgânicas. Deoxinivalenol (DON) tinha concentração mais alta 42,40% (P≤ 0,05) na silagem de fazendas convencionais. Ácidos graxos voláteis (AGV), ácido lático, etanol, pH e nitrogênio de amônia mostraram que as amostras de silagem de fazendas orgânicas e convencionais tinham boa qualidade. Nosso estudo sugere diferenças na formação biogênica de amônia ou micotoxinas em silagem de fazendas orgânicas ou convencionais mas, em geral, os valores medidos foram muito baixos para serem relevantes à saúde animal. Ademais, essas diferenças podem ser devido à diferença na matéria sólida e maturidade da planta entre as amostras de silagem orgânica e convencional.(AU)


Assuntos
Aminas Biogênicas/análise , Ácidos Graxos Voláteis , Micotoxinas/análise , Agricultura Orgânica , Poaceae , Amônia/análise , Etanol/análise , Ácido Láctico/análise , Padrões de Referência
17.
Arq. bras. med. vet. zootec. (Online) ; 69(2): 269-277, mar.-abr. 2017. tab
Artigo em Inglês | VETINDEX | ID: vti-16632

Resumo

The aim of the current study was to investigate biogenic amines and mycotoxins concentrations in baled silage (mainly Poaceae family grasses) prepared in organic and conventional farms and to relate these parameters to fermentative parameters. The mean dry matter (DM) content was 364.10±93.31 and 424.70±95.93g/kg in the silage from organic and conventional farms respectively. The silage samples from organic farms had 17.00% higher (P≤ 0.05) tyramine (TY) than the silage from conventional farms. Conventional farm samples were characterized by 46.00% higher histamine (HIS) (P≤ 0.05), 9.80% higher putrescine (PUT) (P≤ 0.05), 17.30% higher cadaverine (CAD) (P≤ 0.05). Aflatoxins (AFL) (total) and zearalenone (ZEN), T-2/HT-2 concentrations were higher respectively 16.00% (P≤ 0.05) and 13.40% (P≤ 0.05), 1.80% (P≤ 0.05) in the silage prepared in organic farms. Deoxynivalenol (DON) concentration was higher 42.40% (P≤ 0.05) in silage from conventional farms. Volatile fatty acids (VFA), lactic acid, ethanol, pH and ammonia nitrogen showed that the silage samples from organic and conventional farms were of good quality. Our study suggests differences in biogenic amine formation or mycotoxins content in silage from organic and conventional farming, but, overall, the measured values are too low to be relevant for animal health. Furthermore, these differences might as well be due to the difference in dry matter content and plant maturity between the organic and conventional silage samples.(AU)


O objetivo do presente estudo foi investigar concentrações de aminas biogênicas micotoxinas em silagem embalada (principalmente gramíneas da família Poaceae) preparada em fazendas orgânicas e convencionais e relacionar esses parâmetros a parâmetros fermentativos. A massa seca média (MS) foi 364,10±93,31 e 424,70±95,93g/kg na silagem de fazendas orgânicas e convencionais, respectivamente. As amostras de silagem de fazendas orgânicas tinham 17% a mais de tyramina (TY) (p≤ 0,05) que as de fazendas convencionais. As amostras de fazendas convencionais foram caracterizadas por histamina (HIS) 46,00% mais alta (P≤ 0,05), 9,80% putrecina (PUT) mais alta (P≤ 0,05), 17,30% de cadaverina (CAD) mais alta (P≤ 0,05). Aflatoxnas (AFL) (total) e zearalenone (ZEN), T-2/HT-2 tinham concentrações mais altas em respectivamente 16,00% (P≤ 0,05) e 13,40% (P≤ 0,05), 1,80% (P≤ 0,05) na silagem preparada em fazendas orgânicas. Deoxinivalenol (DON) tinha concentração mais alta 42,40% (P≤ 0,05) na silagem de fazendas convencionais. Ácidos graxos voláteis (AGV), ácido lático, etanol, pH e nitrogênio de amônia mostraram que as amostras de silagem de fazendas orgânicas e convencionais tinham boa qualidade. Nosso estudo sugere diferenças na formação biogênica de amônia ou micotoxinas em silagem de fazendas orgânicas ou convencionais mas, em geral, os valores medidos foram muito baixos para serem relevantes à saúde animal. Ademais, essas diferenças podem ser devido à diferença na matéria sólida e maturidade da planta entre as amostras de silagem orgânica e convencional.(AU)


Assuntos
Aminas Biogênicas/análise , Micotoxinas/análise , Agricultura Orgânica , Poaceae , Ácidos Graxos Voláteis , Padrões de Referência , Ácido Láctico/análise , Etanol/análise , Amônia/análise
18.
Tese em Português | VETTESES | ID: vtt-221665

Resumo

Essa pesquisa buscou avaliar os efeitos tóxicos das principais micotoxinas de interesse na avicultura brasileira, trazendo em um único estudo a mensuração os efeitos tóxicos causados por aflatoxinas, fumonisinas, deoxinivalenol e toxina T-2 em frangos de corte, avaliando marcadores de danos oxidativos, bioquímica sérica, análise da microbiota cecal e morfometría jejunal. Foram utilizados 60 pintos, machos, mantidos de 1-28 dias de idade. Os animais foram dispostos aleatoriamente em 5 grupos, sendo: T1 (dieta basal, controle negativo), T2 (dieta basal + 2,8 mg.kg-1 de aflatoxinas), T3 (dieta basal + 120 mg.kg-1 de fumonisinas), T4 (dieta basal + 50 mg.kg-1 de deoxinivalenol) e T5 (dieta basal + 3 mg.kg-1 de toxina T-2). Foram realizadas as seguintes análises na bioquímica sérica: proteínas totais, albumina, ácido úrico, colesterol, triglicerídeos, cálcio, fósforo, alanino aminotransferase (ALT) e aspartato aminotransferase (AST). No plasma dos frangos utilizados no estudo foram mensurados as substâncias reativas ao ácido tiobarbitúrico (TBARS), proteína carbonilada (CARB) e a capacidade antioxidante total (TAC). Um fragmento de jejuno foi coletado para avaliação da altura das vilosidades e profundidade de criptas. Já do conteúdo cecal desses animais, foram feitos cultivos e contagem Lactobacillus spp. e coliformes totais. A presença de aflatoxinas na dieta das aves promoveu decréscimo nos níveis séricos de proteínas totais, albumina e colesterol. Fumonisinas promoveram aumento da atividade de AST. A adição de toxina T-2 na dieta dos frangos levou ao aumento da atividade de ALT e decréscimo nos níveis de proteínas totais. Deoxinivalenol não alterou os parâmetros bioquímicos no presente estudo e os níveis de ácido úrico e triglicerídeos não foram alterados com a presença das micotoxinas testadas nas dietas. A altura das vilosidades foi modificada com a presença de aflatoxinas e fumonisinas na ração e deoxinivalenol foi capaz de diminuir a profundidade de criptas e com isso alterar a relação vilosidade/cripta. Já, a contagem de coliformes totais no ceco das aves foi aumentada em todos os tratamentos contaminados com micotoxinas, entretanto a contagem de Lactobacillus spp. não foi alterada no presente estudo. O nível de TBARS e CARB no plasma dos animais não sofreu alteração com a presença de micotoxinas nas dietas, porém a TAC foi aumentada nos tratamentos com aflatoxinas e deoxinivalenol. Os dados obtidos no presente estudo mostram os efeitos micotoxinas sobre os parâmetros bioquímicos séricos, estresse oxidativo, bem como a capacidade desses metabólitos tóxicos de afetarem o intestino e interagir com a microbiota desse órgão.


This research aims to evaluate the toxic effects of the main mycotoxins of interest in the Brazilian poultry industry, drawing in a single study to measure the toxic effects caused by aflatoxins, fumonisins, deoxynivalenol and T-2 toxin in cutting strips, evaluating markers of biochemical damage serums, analysis of the cecal microbiota and jejuna morphometri. Sixty male chicks kept from 1-28 days of age were used. The animals were randomly divided into 5 groups: T1 (basal diet, negative control), T2 (basal diet + 2.8 mg.kg-1 of aflatoxins), T3 (basal diet + 120 mg.kg-1 of fumonisins), T4 (basal diet + 50 mg.kg-1 deoxynivalenol) and T5 (basal diet + 3 mg.kg-1 toxin T-2). The following analyzes were performed in serum biochemistry: total proteins, albumin, uric acid, cholesterol, triglycerides, calcium, phosphorus, alanine aminotransferase (ALT) and aspartate aminotransferase (AST). In the plasma of the poultrys used in the study, thiobarbituric acid reactive substances (TBARS), carbonyl protein (CARB) and total antioxidant capacity (TAC) were measured. A jejunum fragment was collected to assess the height of villi and crypt depth. From the cecal content of these animals, cultures and counting Lactobacillus spp. and total coliforms. The presence of aflatoxins in the diet of poultrys promoted a decrease in serum levels of total protein, albumin and cholesterol. Fumonisins promoted an increase in AST activity. The addition of T-2 toxin in the poultry diet led to an increase in ALT activity and a decrease in total protein levels. Deoxynivalenol did not change the biochemical parameters in the present study and uric acid and triglyceride levels were not altered with the presence of mycotoxins tested in the diets. The height of the villi was modified with the presence of aflatoxins and fumonisins in the feed and deoxynivalenol was able to decrease the depth of crypts and thus alter the villous/crypt ratio. The total coliform count in the cecum of birds was increased in all treatments contaminated with mycotoxins, however the count of Lactobacillus spp. was not changed in the present study. The level of TBARS and CARB in the animals' plasma did not change with the presence of mycotoxins in the diets, but the TAC was increased in treatments with aflatoxins and deoxynivalenol. The results show the effects of mycotoxins on serum biochemical parameters, oxidative stress, as well as the ability of these toxic metabolites to affect the intestine and interact with the microbiota of this organ.

19.
Tese em Português | VETTESES | ID: vtt-220320

Resumo

A inclusão de aditivos antimicotoxinas (AAMs) em rações para aves é uma das principais estratégias para reduzir os efeitos prejudiciais das micotoxinas. AAMs são substâncias capazes de adsorver, inativar, neutralizar ou biotransformar micotoxinas. O objetivo deste trabalho foi desenvolver uma metodologia ex vivo para avaliação de AAMs utilizados na produção avícola. Explantes jejunais de frangos de corte destinados ao consumo humano foram utilizados em dois estudos para testar a eficácia de AAMs frente à aflatoxina B1 (AFB1) e ao deoxinivalenol (DON); o efeito direto de DON sobre as vilosidades intestinais também foi investigado. Quatro pares de câmaras de Ussing com área de contato intestinal de 1,0 cm² foram mantidas a 37 ºC e borbulhadas com carbogênio durante 120 min. No estudo 1, seis AAMs disponíveis comercialmente (aditivo antimicotoxinas - AAM 1 a 6) tiveram sua capacidade de reduzir a absorção intestinal de AFB1 avaliada a fim de verificar eficácia. Explantes jejunais (n=4/ave) foram obtidos de 60 frangos no abate, totalizando 240 amostras (40 amostras/AAM). Os explantes foram submetidos a dois tratamentos por AAM: T1 (controle) - 2,8 mg/L de AFB1 e T2 - 2,8 mg/L de AFB1 + 0,5% AAM. Os AAMs também foram testados in vitro para avaliar a adsorção de AFB1 em fluido intestinal artificial. O estudo 2 analisou o impacto deletério de DON sobre as vilosidades intestinais e a eficácia de um AAM. Dois experimentos foram conduzidos para avaliar parâmetros histopatológicos e imunohistoquímicos: Experimento 1) T1 (controle positivo) - somente solução tampão, e T2 - 10 mg/L de DON (duas replicatas/tratamento); e Experimento 2) T1 (controle positivo) - somente solução tampão, T2 (controle negativo) - 10 mg/L de DON, T3 - somente o AAM (0,5%) e T4 - 10 mg/L de DON + 0,5% AAM. Explantes jejunais (n=4/ave) foram obtidos de 22 frangos no abate, totalizando 88 amostras (40 e 48 amostras para os experimentos 1 e 2, respectivamente). Os resultados do estudo 1 demonstraram que AAM1 ao AAM6 reduziram a absorção intestinal de AFB1 nos ensaios ex vivo em 67,11%, 73,82%, 80,70%, 85,86%, 86,28% e 82,32%, respectivamente; já nos testes in vitro, AAM1 ao AAM6 apresentaram adsorção de 99,72%, 99,37%, 99,67%, 99,53%, 99,04% e 99,15%, respectivamente. Não houve correlação entre os achados ex vivo e in vitro. Quanto ao estudo 2, DON reduziu o tamanho dos enterócitos e de seus núcleos e aumentou a vacuolização do citoplasma, o desnudamento do ápice das vilosidades e o número de células apoptóticas no Experimento 1; os parâmetros investigados no Experimento 2 revelaram que o uso do AAM mitigou os efeitos prejudiciais de DON sobre as vilosidades intestinais. A presente avaliação demonstra que o modelo ex vivo utilizando explantes intestinais de frangos de corte montados em câmaras de Ussing é uma ferramenta viável para complementar ensaios in vitro e in vivo empregados na avaliação da eficácia de AAMs e também para a triagem de novos compostos. Além disso, essa metodologia pode ser aplicada para determinar o impacto negativo de DON na integridade do epitélio intestinal de frangos de corte


Inclusion of antimycotoxins additives (AMAs) in poultry feed is one of the main strategies to reduce the harmful effects of mycotoxins. AMAs are substances capable of adsorbing, inactivating, neutralizing or biotransforming mycotoxins. This work aimed to develop an ex vivo methodology to evaluate AMAs used in poultry production. Intestinal explants from broiler chickens destined to human consumption were used in two studies to test the efficacy of AMAs against aflatoxin B1 (AFB1) and deoxynivalenol (DON); the direct effect of DON upon intestinal tissue was also investigated. Four pairs of Ussing chambers with an intestinal contact area of 1.0 cm² were used at 37°C and bubbled with carbogen gas for 120 min. In study 1, six commercially available AMAs (antimycotoxins additive - AMA 1 to 6) had their ability to reduce intestinal absorption of AFB1 evaluated in order to assess efficacy. Jejunal explants (n=4/bird) were collected from 60 broilers at slaughter, totaling 240 samples (40 samples/AMA). The explants were subjected to two treatments per AMA: T1 (control) - 2.8 mg/L of AFB1, and T2 - 2.8 mg/L of AFB1 + 0.5% AMA. The AMAs were also tested in vitro to investigate AFB1 adsorption in artificial intestinal fluid. Study 2 analyzed the detrimental impact of DON on intestinal tissue as well as the efficacy of an AMA. Two experiments were conducted to examine histopathological and immunohistochemical parameters: Experiment 1) T1 (positive control) - buffer solution only, and T2 - 10 mg/L DON (two replicates/treatment); and Experiment 2) T1 (positive control) - buffer solution only, T2 (negative control) - 10 mg/L DON, T3 - AMA (0.5%) only, and T4 - 10 mg/L DON + 0.5% AMA. Jejunal explants (n=4/bird) were taken from 22 broilers at slaughter, totaling 88 samples (40 and 48 samples for experiments 1 and 2, respectively). Results of study 1 showed that AMA1 to AMA6 decreased intestinal absorption of AFB1 in the ex vivo assays by 67.11%, 73.82%, 80.70%, 85.86%, 86.28% and 82.32%, respectively; as for the in vitro tests, AMA1 to AMA6 presented an adsorption of 99.72%, 99.37%, 99.67%, 99.53%, 99.04% and 99.15%, respectively. No correlation was seen between ex vivo and in vitro findings. Regarding the second study, DON reduced the size of enterocytes as well as of their nuclei and increased cytoplasmic vacuolization, apical denudation of villi and the number of apoptotic cells in Experiment 1; the parameters investigated in Experiment 2 evidenced that the AMA mitigated the harmful effects of DON upon intestinal villi. The present assessment demonstrates that the ex vivo model using intestinal explants from broiler chickens mounted on Ussing chambers is a viable tool to complement in vitro and in vivo assays employed to evaluate the efficacy of AMAs and also to screen new compounds. Moreover, this methodology may be applied to determine the burden imposed by DON on the integrity of the intestinal epithelium of broilers

20.
Tese em Português | VETTESES | ID: vtt-222009

Resumo

A alimentação não convencional para cães, comumente denominada alimentação natural, tem ganhado o mercado com a promessa de oferecer um alimento mais saudável, natural e livre dos aditivos utilizados nas indústrias. Porém, os estudos são escassos e não corroboram com essas especulações. Foram adquiridas 44 amostras de 15 empresas que comercializavam seus produtos na cidade de Belo Horizonte (MG), com variados ingredientes. Foram realizadas observações sobre as características dos produtos, além da análise bromatológica em 15 amostras, sendo uma de cada empresa, para quantificação do teor de proteína bruta, extrato etéreo, fibra em detergente neutro, fibra em detergente ácido, cálcio e fósforo, pesquisa bacteriológica em uma amostra e micológica em 12 amostras, além da pesquisa das micotoxinas aflatoxinas, fumonisinas, deoxinivalenol, T2, ocratoxina e zearalenona em 44 amostras. Como principais resultados, foi observado que somente seis empresas possuíam registro no MAPA. Sobre a composição do produto, somente 60% das empresas informaram em rótulo. Constatou-se inadequação em amostras de duas empresas que forneceram os alimentos com peso inferior ao informado na embalagem, chegando a 25% do peso descrito em forma de água livre. Já na análise bromatológica, somente 40% das empresas suplementaram os alimentos com alguma fonte de vitaminas e/ou minerais, e apenas uma apresentou relação Ca:P entre 1:1 e 2:1, conforme recomendado para a espécie. Com exceção de uma amostra, todas apresentaram teor de proteína bruta acima de 30% na matéria seca, contendo cortes cárneos padrão de consumo humano. Sobre a pesquisa microbiológica, foram isoladas as bactérias Enterobacter cloacae e Buttiauxella sp e também foram isolados fungos micotoxigênicos em 58% das amostras analisadas. Já na pesquisa de micotoxinas, foi encontrado um total de 27% das amostras contaminadas, sendo 23% com T-2 e 4% com aflatoxinas. Diante do apresentado, conclui-se que os alimentos não convencionais analisados nesse estudo, apresentaram risco micotoxicológico e poderiam provocar deficiências nutricionais


Unconventional dog food, commonly referred to as natural dog food, has been gaining market share with the promise of offering a healthier, natural, and additive-free dog food. However, studies are scarce and do not support these speculations. A total of 44 samples were acquired from 15 companies that commercialized their products in the city of Belo Horizonte (MG), with varied ingredients. Observations on the characteristics of the products were made, in parallel with bromatological analysis in 15 samples, one from each company, to quantify the content of crude protein, ethereal extract, neutral detergent fiber, acid detergent fiber, calcium and phosphorus, bacteriological research in one sample and mycological research in 12 samples. In addition to research of the mycotoxins aflatoxins, fumonisins, deoxynivalenol, T2, ochratoxin and zearalenone in 44 samples. As main results, it was observed that only six companies were registered in MAPA. About the composition of the product, only 60% of the companies informed on the label. Inadequacy was found in samples from two companies that supplied the food with weight lower than that informed on the package, as much as 25% of the described weight was free water. As for the bromatological analysis, only 40% of the companies supplemented the food with some source of vitamins and/or minerals, and only one presented a Ca:P ratio between 1:1 and 2:1, as recommended for the species. With the exception of one sample, all had crude protein content above 30% in dry matter, containing standard cuts of meat for human consumption. About the microbiological research, Enterobacter cloacae and Buttiauxella sp bacteria were isolated, and mycotoxigenic fungi were also isolated in 58% of the analyzed samples. In mycotoxin research, 27% of the samples were found to be contaminated, 23% with T-2 and 4% with aflatoxins. In view of the presented, it is concluded that the unconventional foods analyzed in this study presented a mycotoxicological risk and could cause nutritional deficiencies.

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