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SUMMARY The epidemiological, clinical and pathological features of a disease syndrome in adult cattle grazing woolly-pod vetch (Vicia villosa ssp dasycarpa) or popany vetch (V benghalensis) are reported. Outbreaks of toxlcosis occurred between midwinter and midsummer in 3 dairy and 6 beef herds on the north coast of New South Wales, between 1982 and 1992. Friesian, Angus, Murray Grey, Guernsey and Hereford breeds were affected. Mean morbidity and case fatality rates in affected herds were 7% (65 of 889) and 69%, respectively. Signs of pruritic dermatitis, illthrift and death were associated with an eosinophilic granulomatous inflammation of many organs, particularly involving the renal cortex, dermis, myocardium, adrenal glands, lymph nodes and hepatic portal triads.  相似文献   
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The objective of this study was to evaluate the effect of retinol (RT) and retinoic acid (RA) on the in vitro development of pre‐implantation goat embryos cultured in potassium simplex optimized medium or synthetic oviduct fluid or cocultured in oviductal cells monolayer either in potassium simplex optimized medium or synthetic oviduct fluid. A total of 2407 cumulus‐oocyte complexes were aspirated from 2 to 6 mm ovarian follicles from slaughtered animals. Selected cumulus‐oocyte complexes were subjected to in vitro maturation in TCM 199 for 24 h at 39°C in an atmosphere of 5% (v/v) CO2 in humidified air. In vitro fertilization was performed in modified defined medium. Eighteen hours after in vitro fertilization, cumulus cells were removed and presumptive zygotes were randomly distributed into experimental groups. In Experiment 1, presumptive zygotes were cultured in potassium simplex optimized medium, potassium simplex optimized medium + RT, potassium simplex optimized medium + retinoic acid, synthetic oviduct fluid, synthetic oviduct fluid + RT and synthetic oviduct fluid + RA at 39°C in a humidified atmosphere of 5% (v/v) CO2, 5% (v/v) O2 and 90% (v/v) N2. In Experiment 2, presumptive zygotes were cocultured in potassium simplex optimized medium + oviductal cells monolayer, potassium simplex optimized medium + RT + oviductal cells monolayer, potassium simplex optimized medium + RA + oviductal cells monolayer, synthetic oviduct fluid + oviductal cells monolayer, synthetic oviduct fluid + RT + oviductal cells monolayer and synthetic oviduct fluid + RA + oviductal cells monolayer in an atmosphere of 5% (v/v) CO2 in humidified air. In both experiments, media were partially changed on day 2 after in vitro fertilization and unfertilized oocytes were excluded from the experiment. Embryos were cultured or cocultured for 8 days. In Experiment 1, there was no effect of RT or RA supplementation on the proportion of oocytes that reached the morula or blastocyst stages. By contrast, Experiment 2 demonstrated that the addition of 0.28 μg/ml RT and 0.5 μm RA to the embryo culture media stimulated (p < 0.05) development to the morula and blastocyst stages under the coculture conditions tested. In conclusion, retinoids play an important role in pre‐implantation development of goat embryos and can be used to enhance in vitro embryo production.  相似文献   
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Toxoplasmosis was diagnosed in a 3-week-old red lory (Eos bornea). Grossly, there was hepatomegaly and pulmonary consolidation. The salient microscopic lesions were multifocal necrotizing mycocarditis, interstitial pneumonia with multifocal necrosis and vasculitis, and multifocal necrotizing hepatitis with periacinar hepatocellular necrosis. Toxoplasma gondii-like organisms were observed in lung, heart, and liver by light and electron microscopy. The organisms in tissues stained with anti-T. gondii serum using an immunohistochemical method.  相似文献   
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Cerebral arteriosclerosis was observed upon necropsy of a 36-yr-old female captive polar bear (Ursus maritimus) that developed a sudden onset of seizure-like activity and died. The medium and large cerebral arteries of the meninges had moderate to severe diffuse discoloration and mineralization of the matrix of the tunica media, with little or no associated cellular reaction. Scanning electron microscopy of the affected arteries showed discrete crystalline calcified deposits in the media and sclerosis of the arterial wall. There were no lesions in the brainstem. The findings suggested a sudden and rapidly fatal loss of blood flow to the brain caused by long-standing arterial lesions. Incidental findings included numerous 0.1- to 10-cm-diameter, hepatic cysts lined with hyperplastic biliary epithelium, a unilateral, unipolar, 3-cm-diameter renal tubular adenoma, and approximately 250 active Baylisascaris sp. nematodes in the intestines.  相似文献   
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Microbial life predominates in the ocean, yet little is known about its genomic variability, especially along the depth continuum. We report here genomic analyses of planktonic microbial communities in the North Pacific Subtropical Gyre, from the ocean's surface to near-sea floor depths. Sequence variation in microbial community genes reflected vertical zonation of taxonomic groups, functional gene repertoires, and metabolic potential. The distributional patterns of microbial genes suggested depth-variable community trends in carbon and energy metabolism, attachment and motility, gene mobility, and host-viral interactions. Comparative genomic analyses of stratified microbial communities have the potential to provide significant insight into higher-order community organization and dynamics.  相似文献   
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