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815.
On a property in the Nelson District, blood and urine samples were taken from red deer (Cervus elaphus) from which low (<1:100) antibody titres to serovar copenhageni and suspected leptospiral abortions had previously been reported. A total of 27 hinds were sampled. Microscopic agglutination test (MAT) titres in sera ranging from 1:32 to 1:128 were found in six animals. Thirteen leptospiral isolations were made from nine of the 27 urine samples. Four of these were typed as copenhageni and nine as hardjo. Two cultures were prepared from each urine sample and hardjo and copenhageni were both isolated from single urine samples from two animals. None of the 27 deer had serum MAT titres at 1:32 or above to copenhageni.  相似文献   
816.
This article describes the surgical procedures for the ovariectomy, ovariohysterectomy and orchidectomy in rodents and rabbits. The indications for each procedure are outlined and effective and safe anesthetics are described. Preoperative and postoperative care is also discussed.  相似文献   
817.
Three trials using 240 weanling pigs were conducted during winter months to determine the influence of nursery temperature ("comfortable" vs "cold") on the response of weanling pigs to added vitamin C (700 ppm) or E (55 IU/kg) to a corn-soybean meal diet. A "comfortable" temperature schedule (27 C initially with a weekly 2 C drop) was maintained in one nursery, with the temperature schedule in the "cold" nursery about 8 C lower. Plasma concentrations of vitamin C and vitamin E were elevated when the respective vitamins were added to the diet, but were not consistently influenced by nursery temperatures. Daily gain, daily feed intake and feed efficiency were not improved with the added C or E. Daily feed intake was increased and feed-to-gain ratios were larger for pigs housed in the "cold" nursery compared with pigs housed in the "comfortable" nursery; however, daily gains were similar in the two environments. Pigs housed in the "cold" nursery were slightly stressed, as indicated by heavier adrenal glands, but the antibody response and serum glucocorticoid concentrations were not significantly affected by either diet or temperature.  相似文献   
818.
819.
Four infectious agents were isolated from the ticks Ixodes ricinus (L.) collected in the recreational area and park-forest of Prague. On the basis of cultivation, staining, biochemical, serologic properties, pathogenicity for animals and histological tests they were identified as Francisella tularensis with the following features: they are short, gram-negative rods of approximate dimensions of 0.3 X 0.8 micron, growing in enriched media after 3-4 day incubation at 37 degrees C. They form small circular, at first transparent, later greyish turbid colonies with regular rims. They are little active biochemically. They are susceptible to streptomycin and some broad spectrum antibiotics. They react positively with tularemic serum, but in lower titres than those in which this serum reacts with standard antigen. The microbes are highly pathogenic for mice, guinea-pigs, young rats, in which a massive bacteriemia occurs before death, but they do not kill rabbits. They multiply well in chick embryo, but do not grow in cell or tissue cultures. The most important histologic changes were observed in liver and spleen of mice. No pathologic changes were found in brain, lungs, heart, kidneys. Necroses were found in liver and in their marginal zones the microbes were present. Conspicuous were changes in numerous hepatocytes which became enlarged due to microbial multiplication and finally transformed into "sacs" packed with microbes. Histological and electronoptical examination showed that these are intracellular parasites fringed with a light lytic zone. Discussed is the problem to what extent the properties of the isolated strains are typical of F. tularensis as well as the importance of their detection from the aspect of epidemiology and differential diagnostics.  相似文献   
820.
A review of the current literature available on feline serum proteins is presented. Early studies concentrated on comparative aspects of species variations in the electrophoretic pattern. The feline electrophoretogram was divided into five basic regions: albumin, alpha-1, alpha-2, beta and gamma. Different subdivisions of these areas were recognized depending on the support medium used. Current papers have compared the relative migration distances of each globulin peak to the migration of albumin. This "Rf" value enables reliable peak identification. To date, no data exists identifying the individual proteins responsible for the peaks in the alpha and beta regions. The only feline globulin to be studied is haptolobin; however its precise location on the electrophoretic strip was not identified.  相似文献   
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