29 research outputs found
DON content in oat grains in Norway related to weather conditions at different growth stages
High concentrations of the mycotoxin deoxynivalenol (DON), produced by Fusarium graminearum have occurred frequently in Norwegian oats recently. Early prediction of DON levels is important for farmers, authorities and the Cereal Industry. In this study, the main weather factors influencing myco-toxin accumulation were identified and two models to predict the risk of DON in oat grains in Norway were developed: (1) as a warning system for farmers to decide if and when to treat with fungicide, and (2) for authorities and industry to use at harvest to identify potential food safety problems. Oat grain samples from farmers’ fields were collected together with weather data (2004–2013)
A mathematical model was developed and used to esti-
mate phenology windows of growth stages in oats (til-
lering, flowering etc.). Weather summarisations were
then calculated within these windows, and the Spearman
rank correlation factor calculated between DON-
contamination in oats at harvest and the weather
summarisations for each phenological window. DON
contamination was most clearly associated with the
weather conditions around flowering and close to har-
vest. Warm, rainy and humid weather during and around
flowering increased the risk of DON accumulation in
oats, as did dry periods during germination/seedling
growth and tillering. Prior to harvest, warm and humid
weather conditions followed by cool and dry conditions
were associated with a decreased risk of DON accumu-
lation. A prediction model, including only pre-flowering
weather conditions, adequately forecasted risk of DON
contamination in oat, and can aid in decisions about
fungicide treatments
Reduced risk of oat grain contamination with fusarium langsethiae and HT-2 and T-2 toxins with increasing tillage intensity
Frequent occurrences of high levels of Fusarium mycotoxins have been recorded in Norwegian oat grain. To elucidate the influence of tillage operations on the development of Fusarium and mycotoxins in oat grain, we conducted tillage trials with continuous oats at two locations in southeast Norway. We have previously presented the content of Fusarium DNA detected in straw residues and air samples from these fields. Grain harvested from ploughed plots had lower levels of Fusarium langsethiae DNA and HT-2 and T-2 toxins (HT2 + T2) compared to grain from harrowed plots. Our results indicate that the risk of F. langsethiae and HT2 + T2 contamination of oats is reduced with increasing tillage intensity. No distinct influence of tillage on the DNA concentration of Fusarium graminearum and Fusarium avenaceum in the harvested grain was observed. In contrast to F. graminearum and F. avenaceum, only limited contents of F. langsethiae DNA were observed in straw residues and air samples. Still, considerable concentrations of F. langsethiae DNA and HT2 + T2 were recorded in oat grain harvested from these fields. We speculate that the life cycle of F. langsethiae differs from those of F. graminearum and F. avenaceum with regard to survival, inoculum production and dispersal
Serum α-tocopherol concentrations in German shepherd dogs with chronic degenerative radiculomyelopathy
The concentration of serum α-tocopherol was measured in German shepherd dogs with chronic degenerative radiculomyopathy, and in German shepherd dogs and dogs of other breeds unaffected by the condition. The mean concentration was significantly higher in German shepherd dogs with the condition than in other breeds of dog unaffected by it, but it was not significantly higher than in unaffected German shepherd dogs. Estimates of components of variance indicated that the concentration varied more widely in individual affected dogs than in unaffected dogs, irrespective of breed. These results suggest that chronic degenerative radiculomyopathy in German shepherd dogs is unlikely to be due to uncomplicated vitamin E deficiency
Aspectos morfolĂłgicos de biĂłpsias musculares em equinos com miopatia sob forma de surto
As miopatias em equinos sĂŁo classificadas de acordo com aspectos clĂnicos, morfolĂłgicos e moleculares, em trĂŞs grandes grupos: nĂŁo associadas ao exercĂcio, associadas ao exercĂcio e devido alteração da condução elĂ©trica do sarcolema. Apesar dos avanços no diagnĂłstico, a literatura ainda relata surtos de miopatia em equinos sem etiologia esclarecida em diversos paĂses. O objetivo desse estudo foi descrever as alterações histolĂłgicas e histoquĂmicas de biĂłpsias musculares de equinos acometidos por miopatia. Sete equinos da raça Quarto de Milha, com 18-24 meses de idade, apresentaram sinais clĂnicos de miopatia. Dentre esses animais, cinco apresentaram sinais subagudos leves a moderados e dois apresentaram sinais hiperagudos severos e decĂşbito lateral. Foram realizadas biĂłpsias musculares utilizando a tĂ©cnica percutânea, por agulha tipo Bergström, no mĂşsculo glĂşteo mĂ©dio em todos os animais acometidos. As amostras foram processadas por meio de tĂ©cnicas histolĂłgicas (HE, TricrĂ´mio de Gomori modificado) e histoquĂmicas (PAS, NADH, ATPase). Nos quadros clĂnicos mais leves, a principal alteração encontrada foi a presença de fibras vermelhas rajadas do tipo I e IIA, que estĂŁo associadas Ă s alterações do metabolismo oxidativo e das funções mitocondriais, como ocorrem nas miopatias mitocondriais. TambĂ©m foram observadas fibras atrĂłficas do tipo I e IIA, alĂ©m da presença de agregados subsarcolemais. Nos quadros mais severos o tecido muscular apresentou infiltrado inflamatĂłrio, aumento de colágeno, fagocitose, necrose, calcificação e regeneração muscular. Diante dos achados morfolĂłgicos, da resposta Ă terapia com vitamina E e Se e da baixa mortalidade quando comparado aos relatos de miopatia atĂpica, conclui-se que esse surto foi desencadeado por lesões mitocondriais, caracterizadas pelas fibras musculares vermelhas rajadas, possivelmente devido uma quebra da homeostase de vitamina E e Se, sendo compatĂvel com o diagnĂłstico de miopatia nutricional