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41.
Half the progeny in a 200-sow herd (2045 pigs) was given feed medicated with 500 g/tonne of a 1:5 trimethoprim/sulphadiazine mixture from three to nine weeks of age. The other half (1989) acted as controls. The trial lasted 12 months. No difference was observed between the two groups in the incidence of streptococcal meningitis and the morbidity and mortality from all disease causes during the growing/fattening periods did not differ significantly. The main diseases encountered were pneumonia (7.24 per cent), streptococcal meningitis (5.12 per cent), leg and foot disorders (3.34 per cent) and the after-effects of vices (1.86 per cent). The resistance of faecal coliforms to trimethoprim was studied during the six-week period of trimethoprim/sulphadiazine feeding. Faecal coliforms in both medicated and non-medicated groups developed almost 100 per cent resistance. However, resistance developed more slowly in the untreated pigs. The medicated pigs showed a small overall improvement in feed conversion rate up to 18 weeks of age mainly because of a marked improvement between three and six weeks.  相似文献   
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The growth and wear rate of claw horn was measured in 42 commercial hybrid pigs. Half received a ration supplemented with 1 mg d-biotin/kg food daily, while the others acted as controls. The start weights of three replicates of 10 pigs averaged 25 kg and their mean finishing weight was 85 kg. Twelve pigs averaged 18 kg at the start and 118 kg at the end of the experiment. No differences in horn growth and wear rates were found between the biotin-supplemented pigs and the controls, or between the front and hind claws, although horn growth and wear both decreased with age. Claw horn grew at an average of 10 mm/28 days in the pigs taken from 25 to 85 kg bodyweight and at 11 mm/28 days in the pigs taken from 18 to 118 kg. The mean rate of wear of claw horn was 6 mm/28 days.  相似文献   
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Whole blood viscosity (WBV) was measured on six healthy horses and ten horses presented for colic surgery. A Wells-Brookfield cone-and-plate microviscometer at 6 rpm was used to determine WBV and WBV was adjusted for packed cell volume (PCV). The ten colic horses were divided into two groups: five horses that died or were euthanatized (group 1) and five horses that were discharged after surgery and medical therapy (group 2). The mean WBV for each group was compared using analysis of variance followed by Duncan multiple-range tests. Mean WBV of group 2 (5.81 +/- 1.48 centipoise [cp]) and normal horses (7.1 +/- 2.3 cp) was significantly (P less than 0.01) lower than group 1 (17.15 +/- 5.71 cp). This preliminary trial shows that horses that died or were euthanatized had a significantly higher WBV than horses surviving. Since viscosity was adjusted for PCV, the differences may represent changes in other factors such as fibrinogen, rouleaux formation, red blood cell deformability, PaO2, or intracellular calcium ion concentration. Thus, increases in WBV in horses with colic may indicate severely compromised regional perfusion that may lead to significant tissue damage. In this preliminary study, it appears that WBV may be a prognostic aid in horses with colic.  相似文献   
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Research mapping is a method of organising research information as part of a process of formulating a research policy in a specific area. A research mapping project was undertaken in the UK, which aimed to map existing and future research into public and green space, to identify gaps in order to help set priorities for future research, and to develop a freely accessible and searchable database of this research. The mapping was structured around two axes. The first axis was of research themes based on The Value of Public Space but developed further and broken down into sub-themes. The second axis was a typology of green and public space based around Planning and Policy Guidance Note 17 (PPG17) with elaboration from Green Spaces, Better Places. Research dating back to 10 years was collected together with information on recently completed, ongoing and planned UK research. Only research meeting specific quality criteria was included. Some information was also collected at a seminar where attendees from a range of organisations were invited to offer their perspectives on where research priorities should be directed. All the material was analysed and the main trends were identified. Three key cross-cutting themes common to much of the research were identified. These are the general lack of baseline surveys against which to assess progress over time; methodological issues, especially the need to standardise data collection methods and techniques; the classification of social groups, currently considered to be too crude.It was found that most research has been undertaken on physical aspects, such as planning and on biodiversity. Economic values have also been a focus, but on a smaller scale. Social research is quite well covered but very patchy. Management is better covered than maintenance. By far the weakest area represented in the research is health and well-being, both in terms of social groups and types of green space. Priorities for further research were then identified.  相似文献   
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Multiple myeloma in a cat   总被引:2,自引:0,他引:2  
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The bone marrow of the dog and cat   总被引:1,自引:0,他引:1  
There is a need for bone marrow biopsy in small animal practice but veterinarians lack knowledge of the technique. In this paper the methods of collecting the marrow sample, its processing and microscopic examination are described. The interpretation of the results is discussed. Résumé. Une biopsie de la moelle des os est nécessaire dans la pratique de petits animaux, mais les vétérinaires manquent de connaissances en ce qui concerne la technique. Dans cet exposé, on décrit les méthodes pour recueillir un spécimen de moelle et son examen microscopique en traitant. On discute de l'interprétation des résultats. Zusammenfassung. Es besteht die Notwendigkeit für Knochenmarkbiopsie in der Kleintierpraxis, jedoch fehlt es Tierärzten an Kenntnis der Technik. In dieser Abhandlung werden die Arten wie man Knochenmarkproben sammelt, sein Verfahren und mikroskopische Untersuchung beschrieben. Die Interpretation der Ergebnisse wird diskutiert.  相似文献   
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