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The effect of a novel lairage environment on the ability of sheep to recover from 16 h of transport was investigated. Sheep were transported from grass paddocks to either novel outside paddocks or inside pens, and housed groups were transported to either familiar or novel inside pens. During transport, sheep from outside paddocks lay down less than those from inside pens. In sheep transported to inside pens, those from outside paddocks spent more time lying and spent less time eating; hay and water intakes during the first 12 h post-transport were lower than those previously kept inside. There was no obvious effect of a novel environment post-transport on blood biochemistry, suggesting that the lower post-transport feed and water intakes in a novel environment did not have a significant effect on the ability of the sheep to recover from the feed and water deprivation associated with transport.  相似文献   
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Hydraulic retention time (HRT) influence improving sludge flocculation with adding the polyelectrolytes (non-ionic, anionic, and cationic) was studied on an activated sludge (AS) system fed with synthetic domestic wastewater (SDW), dairy industry wastewater (DIW), and caramel industry wastewater (CIW). The sludge volumetric index, food/microorganism ratio (F/M), and mixed liquor volatile suspended solids at different HRTs (6, 8 and 10 h) were monitored on an experimental model. Results showed that both SDW and IW had the best sludge flocculation conditions at 8 h and 100 mL of non-ionic polyelectrolyte (0.2 mg L?1). In addition, this phenomenon reached the organic matter removal efficiencies of 95.9, 95.7, and 94.2% for SDW, DIW, and CIW, respectively. Therefore, optimum HRT increased the organic matter removal efficiencies by 10%, sludge concentration by 37% (22–55%), and F/M ratio by 70%. Moreover, the polyelectrolytes used in AS improved the sludge flocculation by 2.9 times.  相似文献   
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Abstract The main question which must be raised when planning to enhance natural populations through sea ranching is whether reared organisms are fit for a life in the wild, or more specifically, whether there are differences between reared and naturally resident individuals. The causes and effects of these differences are reviewed, and results from the Norwegian enhancement programme, which compared reared and wild individuals of Atlantic salmon, Salmo salar L., Atlantic cod, Gadus morhua L., and European lobster, Homarus gammarus L., are discussed with emphasis on morphological and behavioural differences. It was concluded that exposure to an artificial rearing environment during ontogeny can affect both the phenotype and the behaviour of the reared individuals, and thereby, their potential for survival after release into the wild as well. Suggestions are made as to how to diminish observed differences, and thereby, improve the survival potential.  相似文献   
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Seroprevalence of Neospora caninum in dairy cattle in Bahia, Brazil.   总被引:2,自引:0,他引:2  
Sera collected from 447 dairy cattle on 14 dairy farms were tested for Neospora caninum antibodies by use of an immunofluorescent antibody technique. Positive reactions with titres > or =1:200 were found in 63 (14.09%) of animals. Neospora positive sera were also tested for Toxoplasma gondii antibodies by using a commercial latex agglutination test. Antibodies to T. gondii were detected in 3 (4.76%) of 63 N. caninum positive sera. These results indicate that N. caninum infection is widespread among dairy cattle in Bahia state.  相似文献   
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Summary Seasonal effects of liming, irrigation, and acid precipitation on microbial biomass N and some physicochemical properties of different topsoil horizons in a spruce forest (Picea abies L.) were measured throughout one growing season. The highest biomass N was recorded in autumn and spring in the upper soil horizons, while the lowest values were obtained in summer and in deeper horizons. The clearest differences between the different soil treatments were apparent in autumn and in the upper horizons. Liming increased the microbial biomass N from 1.7% of the total N content to 6.8% (Olf1 layer) and from 1% to 2% of the total N content in the Of2 layer. The main inorganic-N fraction in the deeper horizons was NO inf3 sup- . An increase in cation exchange capacity was observed down to the Oh layer, while soil pH was only slightly higher in the Olf1 and Of2 layers after liming. The effects of irrigation were less marked. The microbial biomass N increased from 1.7% of total N to 4.8% in the Olf1 layer and from 1% to 2% of total N in the Of2 layer. In the Olf1 layer an increase in C mineralization was observed. Acid precipitation decreased the microbial biomass N in the upper horizons from 4.8% of total N to 1.8% in the Olf1 layer and from 2% to 0.5% in the Of2 layer. No significant changes in soil pH were observed, but the decrease in cation exchange capacity may result in a decrease in the proton buffering capacity in the near future.  相似文献   
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Paramphistome infections are very common in ruminants and may induce clinical signs, but little is known about effective treatments. In this study, the efficacy of oxyclozanide against Calicophoron daubneyi was studied in goats and its activity tested against immature stages (10 days post-infection) at a dose of 22.5mg/kg bodyweight (BW) and against adult stages using two doses (15 and 22.5mg/kg BW). There was a reduction (82%) in the number of immature worms (compared to controls) but the result was not statistically significant. When tested against adult stages, however, oxyclozanide reduced the worm burdens by 95.6% and 95.9% at doses of 15 and 22.5mg/kg BW, respectively, with no significant difference between the two doses. The experiment demonstrated that oxyclozanide is highly effective in reducing the number of adult paramphistomes in goats.  相似文献   
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