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排序方式: 共有226条查询结果,搜索用时 31 毫秒
1.
Marian Dawkins 《British poultry science》1981,22(3):255-263
1. Battery‐kept hens (Sykes Tints) showed a preference for a large (0.76 x 0.86 m) over a small (0.38 x 0.43 m) cage, but preferred the smaller cage when this had a litter floor to the one 4 times larger with a wire floor.
2. The hens still showed a preference for litter when they could obtain access to it only by entering an even smaller cage (0.38 x 0.215 m) in which they could hardly turn round. This cage gave far less space than that recommended by the UK Welfare Codes (1971).
3. The experiments described demonstrate that hens prefer larger to smaller cages and litter floors to wire ones, but that they give highest priority to flooring. Increasing the space allowed to battery‐kept hens may not therefore be as “valuable” to them as giving them access to litter. 相似文献
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Tracey Jones Ruth Feber Gabriel Hemery Paul Cook Katy James Curt Lamberth Marian Dawkins 《Agricultural Systems》2007
The commercial, welfare and environmental impacts of rearing small colonies of free-range chickens in newly planted woodland at two sites in the UK, during the first 2 years of the enterprise, were investigated. Newly planted rather than established trees were used so that commercially viable species could be planted in a way that would suit the management of the chicken enterprise, and small colonies were used so that farmers wishing to diversify could buy into the system progressively. It was anticipated that marketing a high specification product would provide an immediate income, whilst waiting for the future investment in trees to grow. 相似文献
4.
A survey of coastal recreational boat fishing was conducted in summer 2006 in the marine reserve of Cap de Creus (NW Mediterranean) to assess the biological and socioeconomic implications of this leisure activity. Recreational boat fishers employ four different fishing techniques: bottom fishing rod, fluixa, trolling and surface fishing rod. Although the targeted species depend on the fishing method used, a total of 33 fish species were identified in the catch (8 were pelagic or benthopelagic and the rest were demersal). Fishing effort was high since fishers fished an average of 4 h/day, 8 days/month and nearly 6 months/year. Apart from the highly varied exploitation of the fauna, recreational fishing in Cap de Creus has a large economic effect on the local economy since the majority of fishers were visitors who were spending holidays in one of the villages belonging to the Park, where most of expenditures related to angling activities were made. Overall, results highlight the pressure that recreational boat fishing exerts on fish communities, particularly on littoral, demersal ones. Considering these biological and socioeconomic implications, the competition between recreational and artisanal fishers for littoral resources and the low level of compliance with the current sport fishing regulations, the implementation of a comprehensive management strategy in Mediterranean costal areas is needed. 相似文献
5.
C. Desbiez P. Caciagli C. Wipf-Scheibel P. Millot L. Ruiz D. Marian G. Dafalla H. Lecoq 《Plant pathology》2019,68(7):1268-1275
Cucumber vein yellowing virus (CVYV) is emerging throughout the Mediterranean Basin, where it causes significant damage to cucumber and melon crops. It has been suggested that CVYV originated from the Middle East and has spread only recently to other areas. In this work, an isolate from Sudan was characterized, and surveys performed in that country between 1992 and 2012 revealed a long-term presence of CVYV with a high molecular variability, showing that the virus has long been endemic in sub-Saharan Africa. Comparison of the full-length sequences of 11 CVYV isolates from different geographic origins revealed recombination events in CVYV populations from the Mediterranean Basin and the Middle East, and evidence for different selection pressures along the genome. These results shed a new light on the evolution of CVYV. 相似文献
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Valladares JE Riera C González-Ensenyat P Díez-Cascón A Ramos G Solano-Gallego L Gállego M Portús M Arboix M Alberola J 《Veterinary parasitology》2001,97(1):15-21
Pharmacokinetic and clinical effectiveness of liposome-encapsulated N-methylglucamine antimoniate (LMA) was performed in dogs suffering from experimental leishmaniosis. LMA was compared with N-methylglucamine antimoniate (MGA), the same drug in its free form. Sb plasma concentrations for LMA were always higher than those for MGA. Mean residence time (MRT), half-life time (t(1/2)) and clearance (Cl) showed that Sb was eliminated slower after liposome administration. The high volume of distribution (Vd) obtained with LMA suggests that Sb could achieve therapeutic concentrations in parasite-infected tissues. Average plasma concentration at steady state (Css(ave)) shows that Sb body concentrations after LMA treatment (9.8 mg/kg Sb, each 24h) would be effective in Leishmania infantum canine infection. Comparing LMA with MGA in a 1-year follow-up we observed no relapses for LMA and total protein and gammaglobulin concentrations were within normal range, while for MGA both began to rise 3 months after treatment. Use of antimonial liposomal formulations may restore effectiveness to an existing drug and reduce toxicity. 相似文献
8.
Nested PCR for diagnosis of canine leishmaniosis in peripheral blood, lymph node and bone marrow aspirates 总被引:1,自引:0,他引:1
A nested polymerase chain reaction (PCR) assay was developed using primers selected from the genomic DNA of Leishmania infantum and applied to the diagnosis of leishmaniosis in peripheral blood in dogs. Blood of 39 dogs of different breeds, all sampled in Catalonia (Spain), were tested for leishmaniosis by enzyme linked immunosorbent assay (ELISA), western blotting (WB) and peripheral blood mononuclear cell (PBMC) culture and nested PCR. Twenty negative controls (healthy dogs less than 1-year-old that had not been exposed to a sandfly season) were also studied. Nineteen of the 39 dogs studied were positive by ELISA and/or WB, and 18 of these had a positive PBMC nested PCR. PBMC nested PCR was negative in all the remaining animals that were negative by serological examination, including the 20 negative controls. Parasitological examination and nested PCR of bone marrow and lymph node aspirate from the 19 dogs positive by serological examination, were also positive. These results indicate that PBMC nested PCR is a sensitive and specific tool to diagnose leishmaniosis in dogs. The use of PBMC has the advantage over bone marrow and lymph node aspirates in that it is a less invasive sample. 相似文献
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This work presents evidence from three different valuation studieson the influence of gender in the formation of forestry-relatedvalues. Previous studies examined gender differences withoutexplicitly considering their interaction with other explanatoryvariables. Three separate studies dealing with forest-relatedgoods and services, revealed statistically significant differencesin peoples' preferences, especially between older women andolder men, and older and younger women. In these studies, althoughthere was no overall difference in preferences attributableto gender, there were significant differences related to ageand income, in combination with gender. 相似文献