Peace Corps offers Third World experience     

V Pedersen  L Spencer 《Journal of the American Veterinary Medical Association》1989,195(1):26-29

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Plasma luteinizing hormone response to increasing doses of synthetic gonadotrophin-releasing hormone in heifers     

A Mikél Jensen  K M Pedersen  J F Agger  A Madej 《Acta veterinaria Scandinavica》1983,24(2):211-224

The dosenresponse relationship for a synthetic gonadotrophin-releasing hormone (GnRH) was studied in normally cycling heifers using the area under the luteinizing hormone (LH) curve as a response parameter. Oestrus was synchronized by an injection of 0.5 mg cloprostenol before the experiment started and after the 3rd treatment with GnRH. Treatment with GnRH as assigned in a Latin square included 5 dose levels (0, 10, 50, 100, 250 μg) and 5 treatment days over a period of 22 days. GnRH was capable of inducing an increase of plasma LH within 30 min after injection. Plasma LH response increased with increasing doses of GnRH, the largest increase being observed when the dose was raised from 50 μg to 100 μg. One heifer did not respond to any of the doses applied. The existence of an individual treshold dose of GnRH is suggested.  相似文献   

A spatial analysis of land cover patterns and its implications for urban avifauna persistence under climate change     

Amin Rastandeh  Maibritt Pedersen Zari 《Landscape Ecology》2018,33(3):455-474

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Pathogenesis of feline enteric coronavirus infection     

Pedersen NC  Allen CE  Lyons LA 《Journal of Feline Medicine and Surgery》2008,10(6):529-541

Fifty-one specific pathogen-free (SPF) cats 10 weeks to 13 years of age were infected with a cat-to-cat fecal-oral passed strain of feline enteric coronavirus (FECV). Clinical signs ranged from unapparent to a mild and self-limiting diarrhea. Twenty-nine of these cats were FECV na?ve before infection and followed sequentially for fecal virus shedding and antibody responses over a period of 8-48 months. Fecal shedding, as determined by real-time polymerase chain reaction (RT-PCR) from rectal swabs, appeared within a week and was significantly higher in kittens than older cats. FECV shedding remained at high levels for 2-10 months before eventually evolving into one of three excretion patterns. Eleven cats shed the virus persistently at varying levels over an observation period of 9-24 months. Eleven cats appeared to have periods of virus shedding interlaced with periods of non-shedding (intermittent or recurrent shedders), and seven cats ceased shedding after 5-19 months (average 12 months). There was no change in the patterns of virus shedding among cats that were excreting FECV at the time of a secondary challenge exposure. Four cats, which had ceased shedding, re-manifested a primary type infection when secondarily infected. Cats with higher feline coronavirus (FCoV) antibody titers were significantly more likely to shed virus, while cats with lower titers were significantly less likely to be shedding. Twenty-two kittens born to experimentally infected project queens began shedding virus spontaneously, but never before 9-10 weeks of age. Natural kittenhood infections appeared to be low grade and abortive. However, a characteristic primary type infection occurred following experimental infection with FECV at 12-15 weeks of age. Pregnancy, parturition and lactation had no influence on fecal shedding by queens. Methylprednisolone acetate treatment did not induce non-shedders to shed and shedders to increase shedding.  相似文献   

Phenylbutazone induces equine glandular gastric disease without decreasing prostaglandin E2 concentrations          下载免费PDF全文

S. K. Pedersen  A. E. Cribb  E. K. Read  D. French  H. E. Banse 《Journal of veterinary pharmacology and therapeutics》2018,41(2):239-245

In equids, phenylbutazone at high doses induces gastric disease, primarily in the glandular portion of the stomach. However, the mechanism of nonsteroidal anti‐inflammatory drug (NSAID)‐induced gastric disease in horses has yet to be determined. While phenylbutazone‐associated ulceration is often attributed to a decrease in basal gastric prostaglandins, this has not been demonstrated in the horse. Twelve horses were randomly assigned to treatment (n  = 6; 4.4 mg/kg phenylbutazone PO in 20 ml molasses q 12 hr for 7 days) or placebo (n  = 6; 20 ml molasses PO q 12 hr for 7 days) groups. Before treatment and 3 and 7 days after initiation of treatment, gastroscopy was performed and glandular gastric biopsies were collected and frozen at ?80°C. Glandular disease was assessed on a scale of 0–4. Prostaglandin E₂ concentrations in biopsies were measured using a commercially available enzyme‐linked immunosorbent assay. All phenylbutazone‐treated horses developed grade ≥2 glandular disease. Prostaglandin concentrations increased over time (p  = .0017), but there was no effect of treatment (p  = .49). These findings indicate that despite induction of glandular disease grade ≥2, phenylbutazone did not decrease basal glandular gastric prostaglandin E₂ concentration.  相似文献   

An assessment of forest sector modeling approaches: conceptual differences and quantitative comparison     

Hanne K. Sjølie  Greg S. Latta  Erik Trømborg  Torjus F. Bolkesjø  Birger Solberg 《Scandinavian Journal of Forest Research》2015,30(1):60-72

Forest sector models are widely used for policy and economic analyses. Basic assumptions vary considerably between models, but little attention has been paid to the impacts these differences may have on model results. Norway provides a great opportunity to fill this void as it has two forest sector models currently in use based on different modeling assumptions, but sharing the same data source. In one model, agents are assumed to be myopic in the meaning that they rely only on the current market conditions. Harvest behavior is in this model based on econometric relations and exogenous forest growth rates. The second model approach employs extensive forest data and assumes that agents have perfect information over the model time horizon. We discuss the differences between the two modeling approaches and compare quantitatively the model results of two case studies. However, both types of models are rather sensitive to changes in assumptions and data. The strengths and weaknesses of the two model approaches and their appropriateness for responding to the study questions should be considered when choosing modeling methodology. Using both models in parallel removes the uncertainty caused by the foresight assumption/optimization routine and thus provides in total more information.  相似文献   

Saponin-containing subfractions of soybean molasses induce enteritis in the distal intestine of Atlantic salmon     

Knudsen D  Urán P  Arnous A  Koppe W  Frøkiaer H 《Journal of agricultural and food chemistry》2007,55(6):2261-2267

The current work aimed at tracing the causative components for soybean-induced enteritis in Atlantic salmon (Salmo salar L.). Soybean molasses was subjected to phase separation using n-butanol. Three subfractions were obtained as follows: butanol phase, precipitate, and water phase. The biochemical composition of soybean molasses and the obtained subfractions were analyzed in detail: Protein, fat, and ash were quantified according to standard methods. Sucrose, raffinose, and stachyose were quantified using high-performance anion-exchange chromatography. Soyasaponins were quantified using reverse-phase high-performance liquid chromatography. Finally, sodium dodecyl sulfate-polyacrylamide gel electrophoresis was used to evaluate the size distribution of the proteins present in each fraction. Molasses and the different subfractions were thereafter fed to Atlantic salmon in two successive fish trials. The level of intestinal inflammation was evaluated by light microscopy using a semiquantitative scoring system. Histological assessments revealed that Atlantic salmon fed a combination of butanol phase and precipitate displayed significant enteritis. Atlantic salmon fed the water phase displayed normal intestinal morphology. The causative components for soybean-induced enteritis withstand butanol treatment and prolonged heating at 70 degrees C. Sucrose, raffinose, stachyose, nor soybean proteins larger than 10 kDa induce enteritis alone. Soyasaponins, or components that follow the same solubility pattern, trigger the inflammatory reaction. We therefore suggest that soybean-induced enteritis in Atlantic salmon is induced by soyasaponins alone or by soyasaponins in combination with other factors, e.g., antigenic soybean proteins or the intestinal microflora.  相似文献   

Characterization of polymeric proteins from vitreous and floury sorghum endosperm     

Ioerger B  Bean SR  Tuinstra MR  Pedersen JF  Erpelding J  Lee KM  Herrman TJ 《Journal of agricultural and food chemistry》2007,55(25):10232-10239

Differences in protein content and composition between vitreous and floury endosperm were investigated using a number of different techniques. Differences in protein cross-linking between vitreous and floury endosperm were investigated using differential solubility, size exclusion chromatography (SEC), and analysis of sulfhydryl content and composition. Vitreous endosperm was found to have higher levels of total protein and kafirins, but floury endosperm had a higher proportion of gamma-kafirins than the vitreous. Floury endosperm was found to have higher levels of SDS-soluble proteins than SDS-insoluble proteins extracted using sonication than vitreous endosperm. Conversely, vitreous endosperm had a greater proportion of the insoluble proteins. SEC analysis of the polymeric proteins revealed that the insoluble proteins had more polymeric proteins than did the soluble proteins, indicating greater cross-linking and a larger Mw distribution. Vitreous endosperm was also found to have a greater percentage (i.e., a higher ratio of disulfide to total sulfhydryls) of disulfide bonds than floury endosperm. These results show that the proteins in vitreous endosperm have a higher degree of cross-linking and a greater Mw distribution than those found in floury endosperm.  相似文献   

Global network reorganization during dynamic adaptations of Bacillus subtilis metabolism     

Buescher JM  Liebermeister W  Jules M  Uhr M  Muntel J  Botella E  Hessling B  Kleijn RJ  Le Chat L  Lecointe F  Mäder U  Nicolas P  Piersma S  Rügheimer F  Becher D  Bessieres P  Bidnenko E  Denham EL  Dervyn E  Devine KM  Doherty G  Drulhe S  Felicori L  Fogg MJ  Goelzer A  Hansen A  Harwood CR  Hecker M  Hubner S  Hultschig C  Jarmer H  Klipp E  Leduc A  Lewis P  Molina F  Noirot P  Peres S  Pigeonneau N  Pohl S  Rasmussen S  Rinn B  Schaffer M  Schnidder J  Schwikowski B  Van Dijl JM  Veiga P  Walsh S  Wilkinson AJ  Stelling J  Aymerich S 《Science (New York, N.Y.)》2012,335(6072):1099-1103

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Dimension and design of the farrowing unit     

Bjarne K. Pedersen 《国外畜牧学(猪与禽)》2012,32(3)

1引言 分娩舍是母猪场中最昂贵的猪舍,同时也是最重要的一个.它应该能够在开展作业时,向母猪、新生仔猪以及工作人员提供一个舒适的环境.分娩舍的设计目标是为了能够培养出尽可能多的仔猪和尽可能高的仔猪断奶体重.当然,技术仅仅是这一等式的一部分;环境温度和管理也发挥了重要的作用.  相似文献