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A new, fatal mycotoxicosis of cattle has been recognised in north-western Australia. A feeding trial confirmed the toxicity of a previously unknown species of Corallocytostroma that grows on Mitchell grass (Astrebla spp). The disease has been colloquially named ‘black soil blindness’ because its most prominent features are its confinement to pastures on black soil, and blindness and death of affected animals. Over 500 cattle have died and considerable subclinical disease is present. Above average wet season rainfall and extended growing seasons may explain the emergence of the fungus. The disease is important because cattle production in large areas of Australia utilise Mitchell grass pastures.  相似文献   
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In this study we investigated the influence of artificial light at night (ALAN) of different intensities (0, 1, 10, 100 lx) and different colours (blue, green, red) on the daily melatonin rhythm and mRNA expression of gonadotropins in roach Rutilus rutilus, a ubiquitous cyprinid, which occur in standing and moderately flowing freshwater habitats of central Europe. Melatonin concentrations were significantly lowered under nocturnal white light already at 1 lx. Low intensity blue, green and red ALAN lowered the melatonin levels significantly in comparison to a dark control. We conclude that ALAN can disturb melatonin rhythms in roach at very low intensities and at different wavelengths and thus light pollution in urban waters has the potential to impact biological rhythms in fish. However, mRNA expression of gonadotropins was not affected by ALAN during the period of the experiments. Thus, suspected implications of ALAN on reproduction of roach could not be substantiated.  相似文献   
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In a longitudinal investigation (3 points of time n = 214, 206 resp. 202) the hemoglobin quota (Hb), the hematocrit (Hct) resp. the average corpuscular hemoglobin concentration (MCHC) were analysed at male calves receiving semi-liquid feed in the transitional period from pre-ruminal to ruminal digestion (56d). Breed, live weight development, consumption of milk, concentrated feed resp. dried forage, diseases of the calves as well as the father and the milk yield resp. the lactation age of the mother were registered as reference conditions. The percentage of calves with an Hb less than 10.5 g/dl was at the three points of time 50.00%, 86.41% resp. 41.58%, of calves with an Hct less than 33,5% it was 43.46%, 66.02% resp. 31.68% and of calves with an MCHC less than 30.5 g Hg/dl erythrocytes 51.87%, 76,21 resp. 47,03%. 21.50%, 33.50% resp. 4.46% of all test animals even had an Hb of less than 8.5 g/dl.  相似文献   
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