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The effects of different combinations of nutritional background, feeding regimes and dietary compositions on growth responses of the Atlantic cod have been examined. Alternating short periods (1–3 weeks) of food deprivation with unlimited provision of food depressed growth below that of controls, but cod that were fed on alternate weeks (1:1) were larger than those that were exposed to 2 or 3 week periods of deprivation and feeding (2:2 or 3:3). Thus, periods of food deprivation of short duration were insufficient to induce any marked compensatory growth response. When cod were deprived of food for longer periods a compensatory growth response was observed. On receiving excess food supplies following 8 weeks of food deprivation the fish grew more rapidly than the controls and had completely recovered body weight within 12 weeks. The greatest compensatory growth response was shown by cod in poor condition (lowest condition factor), because at the end of an 18 week growth trial there were no differences in body weight between fish irrespective of their initial condition. Both sexes displayed a compensatory growth response.  相似文献   
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Dexamethasone-induced parturition in cattle   总被引:1,自引:0,他引:1  
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Ketoprofen is a nonsteroidal anti‐inflammatory and analgesic agent that nonselectively inhibits cyclooxygenase, with both COX‐1 and COX‐2 inhibition. Recent studies on COX receptor expression in reptiles suggest that nonselective COX inhibitors may be more appropriate than more selective inhibitors in some reptiles, but few pharmacokinetic studies are available. The goal of this study was to determine single‐ and multidose (three consecutive days) pharmacokinetics of racemic ketoprofen administered intravenously and intramuscularly at 2 mg/kg in healthy juvenile loggerhead turtles (Caretta caretta). The S‐isomer is the predominant isomer in loggerhead sea turtles, similar to most mammals, despite administration of a 50:50 racemic mixture. Multidose ketoprofen administration demonstrated no bioaccumulation; therefore, once‐daily dosing will not require dose adjustment over time. S‐isomer pharmacokinetic parameters determined in this study were Cmax of 10.1 μg/ml by IM injection, C0 of 13.4 μg/ml by IV injection, AUC of 44.7 or 69.4 μg*hr/ml by IM or IV injection, respectively, and T½ of 2.8 or 3.6 hr by IM or IV injection, respectively. Total ketoprofen plasma concentrations were maintained for at least 12 hr above concentrations determined to be effective for rats and humans. A dose of 2 mg/kg either IM or IV every 24 hr is likely appropriate for loggerhead turtles.  相似文献   
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A Fusarium sp. root pathogen of lupin is the causal agent of the most important disease that affects the cultivation of white lupin (Lupinus albus L.) in Egypt. The aim of our research was to investigate whether host resistance to Fusariumroot disease was available in Egyptian landraces ofLupinus albus. Five Fusarium isolates collected from white lupin samples in Egypt were tested with an Egyptian landrace and a French cultivar. The most aggressive isolate was used to screen an additional 15 Egyptian landraces, two cultivars released in Egypt after selection among landraces, one Polish cultivar, and two French cultivars. The assessment of host response to Fusarium was performed in a field, and under controlled conditions in a greenhouse pot experiment. Most landraces and the two Egyptian cultivars showed better resistance with good accordance between field and pot experiment. This experiment showed that Egyptian genetic resources of white lupin possess partial resistance to Fusarium root rot. Egyptian germplasm may be an alternative genetic source for incorporating partial resistance to Fusarium root rot into the breeding pools. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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