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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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Mast cell tumors are among the most commonly seen tumors of the skin in dogs and are more highly aggressive than mast cell tumors of other species. Some breeds display a markedly higher incidence of mast cell tumor development than others and appear to have some genetic predisposition. Recently, mutations have been found in canine mast cell tumor tissues and cell lines within the juxtamembrane domain of the protooncogene c-KIT In previous studies utilizing a small number of cases, no association between the presence of a mutation and the breed of dog or grade of the tumor could be identified. An expanded study with a larger sample set was performed to explore this possibility. The juxtamembrane domain of c-KIT was amplified using the polymerase chain reaction from genomic DNA preparations of 88 paraffin-embedded mast cell tumors from selected breeds. Mutations, consisting of duplications and deletions, were found in 12 of the tumors. A significant association was found between the presence of a mutation and a higher grade of tumor but not between breed and grade or between breed and the presence of a mutation.  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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