Intensive polyculture of fish in freshwater ponds. I. Substitution of expensive feeds by liquid cow manure     

Rom Moav  G. Wohlfarth  G.L. Schroeder  G. Hulata  H. Barash 《Aquaculture (Amsterdam, Netherlands)》1977,10(1):25-43

In 1974 and 1975 nine experimental treatments of fish polyculture in stagnant water ponds without aeration were conducted at Dor. The polyculture was composed of common carp, silver carp, white amur (grass carp) and Tilapia. The treatments differed in stocking densities, feeding and manuring levels. The most productive treatment of the experiment, in which the fish were fed with protein-rich pellets, produced 50 kg/ha per day, probably a record for unaerated ponds of stagnant water. Two treatments (low and high stocking densities) fed exclusively with liquid cow manure produced an average yield of around 32 kg/ha per day. The yields of the treatments receiving high-protein pellets exceeded those of the treatments receiving grain pellets by 20 and 9.6 kg/day per ha, at high and low stocking densities, respectively, and in both cases the yield increments justified the extra cost of high-protein feed. The responses of the four fish species to the different levels of feeding and stocking densities were widely different. The common carp and white amur showed the greatest responses to increased feeding inputs while the silver carp and Tilapia, even at high densities, have done equally well at low feeding levels. Total body fat contents of the common carp were 20%, 15% and 6.2% when fed with high-protein pellets, grains pellets and liquid cow manure, respectively. Intermittent harvesting did not result in increased yields.  相似文献   

Retention of aspen (Populus tremulae) at final cuttings - The effect of dead wood characteristics on saproxylic beetles     

Leif Martin Schroeder  Erik SahlinHeidi Paltto 《Forest Ecology and Management》2011,262(5):853-862

To preserve biodiversity in managed forest landscapes dead and living trees are retained at final cuttings. In the present study we evaluated the effect of these practices for saproxylic (wood-dependent) beetles inhabiting dead aspen trees (Populus tremulae). For saproxylic beetles, tree retention at final cuttings can be expected to be especially valuable for species adapted to sun-exposed dead wood, a substrate that only rarely occurs in well managed forest stands. Therefore, the current evaluation was conducted as a comparison of species richness, species density (number of species per sample), assemblage composition and occurrence of individual species between clear-cuts, where aspen trees were retained, and closed forest stands with aspen trees. The study was conducted in central Sweden and the beetles were sampled by sieving of bark from CWD (coarse woody debris) of aspen. There was no significant difference in rarefied species richness between forest and clear-cut sites. Species composition differed significantly between the two stand types. Generalized linear mixed-effects models predicted the species density to be 34% lower in CWD objects in forest sites than on clear-cuts. This pattern could partly be explained by differences in CWD diameter, decay class and bark types between the two stand types (clear-cut/forest). Stand type was a significant predictor of occurrence in individual CWD objects for 30% of analysed individual beetle species. For all species except one, the variable stand type predicted higher occurrence on clear-cuts than in forest stands. To conclude, our results demonstrate that retention of aspen on clear-cuts contributes to population recruitment of a different assemblage of species than CWD within stands.  相似文献   

Zur Klassifizierung hydromorpher Böden     

Diedrich Schroeder 《植物养料与土壤学杂志》1967,116(3):199-207

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Welte,E, und Timmermann,F.: Düngung und Umwelt. DIN A 5, 96 Seiten,kartoniert. Verlag W. Kohlhammer,Stuttgart und Mainz, 1985. ISBN 3–17–3320–4, 18,00 DM     

D. Schroeder 《植物养料与土壤学杂志》1986,149(3):359-360

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Preliminary safety and biological efficacy studies of ethyl pyruvate in normal mature horses     

Schroeder EL  Holcombe SJ  Cook VL  James MD  Gandy JC  Hauptman JG  Sordillo LM 《Equine veterinary journal》2011,43(3):341-347

Reasons for performing the study: Endotoxaemia causes substantial morbidity and mortality in horses with colic and sepsis. Ethyl pyruvate is a novel anti‐inflammatory medication that improved survival in preclinical models of severe sepsis endotoxaemia and intestinal ischaemia and reperfusion in rodents, swine, sheep and dogs and may be a useful medication in horses. Hypothesis: Ethyl pyruvate has no adverse effects in normal horses and is biologically active based on suppression of proinflammatory gene expression in endotoxin stimulated whole blood, in vitro. Methods: Physical and neurological examinations, behaviour scores, electrocardiograms and clinicopathological tests were performed on 5 normal healthy horses receiving 4 different doses of ethyl pyruvate. Doses included 0, 50, 100 and 150 mg/kg bwt administered in a randomised crossover design with a 2 week washout period between doses. Biological efficacy was assessed by stimulating whole blood with endotoxin from the horses that received ethyl pyruvate prior to and 1 and 6 h after drug infusion. Gene expression for TNFα, IL‐1β and IL‐6 was assessed. Results: There were no effects of drug or dose (0, 50, 100 or 150 mg/kg bwt) on any of the physical or neurological examination, behaviour factors, electrocardiogram or clinical pathological results collected from any of the horses. All parameters measured remained within the normal reference range. There was a significant reduction in TNFα, IL‐1β and IL‐6 gene expression in endotoxin stimulated whole blood from horses 6 h after receiving 150 mg/kg bwt ethyl pyruvate. There were no detectable effects on gene expression of any of the other doses of ethyl pyruvate tested. Conclusion: We were unable to detect any detrimental effects of ethyl pyruvate administration in normal horses. Ethyl pyruvate significantly decreased proinflammatory gene expression in endotoxin stimulated blood 6 h after drug administration. Clinical relevance: Ethyl pyruvate may be a safe, effective medication in endotoxaemic horses.  相似文献   

Histopathological,Immunohistochemical, Lectinhistochemical and Molecular Findings in Spontaneous Bovine Abortions by Campylobacter fetus     

EL Morrell  CG Barbeito  CA Odeón  EJ Gimeno  CM Campero 《Reproduction in domestic animals》2011,46(2):309-315

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Food intake and growth of German shepherd puppies     

G. E. Schroeder  G. A. Smith 《The Journal of small animal practice》1994,35(11):587-591

The nutritional programme followed during the growth and development of the German shepherd puppy may have a significant influence on the dog's value as a potential working or breeding animal. Limited research has been undertaken on the nutrition of the dog from birth until four to five weeks of age. The objective of this study was to establish a baseline in terms of food intake and growth, which can be used in a nutritional and managerial programme in a commercial breeding unit. The food intake and growth of 10 German shepherd dog litters, with an average of six puppies per litter, were monitored from birth to 12 weeks of age. Both food intake and growth was described by regression equations. A commercially available diet was fed throughout the study. Performance criteria, namely food intake and bodyweight, were established which could be used in a commercial German shepherd dog breeding unit.  相似文献   

Effects of energy supply on leucine utilization by growing steers at two body weights     

Schroeder GF  Titgemeyer EC  Moore ES 《Journal of animal science》2007,85(12):3348-3354

The effects of energy supplementation on Leu utilization in growing steers were evaluated in 2 experiments by using 6 ruminally cannulated Holstein steers. In Exp. 1, steers (initial BW = 150 +/- 7 kg) were limit-fed (2.3 kg of DM/d) a diet based on soybean hulls and received a basal ruminal infusion of 100 g of acetate/d, 75 g of propionate/d, and 75 g of butyrate/d, as well as abomasal infusions of 200 g of glucose/d and a mixture (215 g/d) containing all essential AA except Leu. Treatments were arranged as a 3 x 2 factorial, with 3 amounts of Leu infused abomasally (0, 4, and 8 g/d) and supplementation of diets with 2 amounts of energy (0 and 1.9 Mcal/d of GE). Supplemental energy was supplied by ruminal infusion of 100 g of acetate/ d, 75 g of propionate/d, and 75 g of butyrate/d, as well as abomasal infusion of 200 g of glucose/d to provide energy to the animal without affecting the microbial protein supply. When no supplemental energy was provided, Leu supplementation increased N balance, with no difference between 4 and 8 g/d of Leu (24.5, 27.0, and 27.3 g/d for 0, 4, and 8 g/d of Leu), but when additional energy was supplied, N retention increased linearly in response to Leu (25.6, 28.5, and 31.6 g/d for 0, 4, and 8 g/d of Leu; Leu x energy interaction, P = 0.06). The changes in N balance were the result of changes in urinary N excretion. The greater Leu retentions in response to energy supplementation when Leu was the most limiting nutrient indicate that energy supplementation improved the true efficiency of Leu utilization. In addition, supplemental energy increased the gross efficiency of Leu utilization when the Leu supply was not limiting by increasing the maximal rates of protein deposition. Experiment 2 was similar to Exp. 1, but steers had an initial BW of 275 +/- 12 kg and were limit-fed at 3.6 kg of DM/d. Retention of N was not affected (P = 0.22) by Leu supplementation, indicating that Leu did not limit protein deposition. Energy supply increased N retention (P < 0.01) independently of Leu supplementation (33.0 vs. 27.8 g/d). Overall, energy supplementation improved Leu utilization by modestly increasing N retention when Leu was limiting and by increasing the ability of steers to respond to the greatest amount of supplemental Leu. We conclude from these results that the assumption of a constant efficiency of AA utilization is unlikely to be appropriate for growing steers.  相似文献   

Distribution Pattern(s) of Sperm Protein at 22 kDa (SP22) on Fresh,Cooled and Frozen/Thawed Equine Spermatozoa and Expression of SP22 in Tissues from the Testes and Epididymides of Normal Stallions          下载免费PDF全文

LMJ Miller  EM Woodward  JR Campos  EL Squires  MHT Troedsson 《Reproduction in domestic animals》2015,50(2):275-282

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Relative importance of habitat characteristics at multiple spatial scales for wood-dependent beetles in boreal forest     

Thomas Ranius  Victor Johansson  Martin Schroeder  Alexandro Caruso 《Landscape Ecology》2015,30(10):1931-1942

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