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81.
Abstract The abundances of Aeromonas salmonicida subsp. salmonicida in the water and in the surface microlayer was studied during the initial phase of a cohabitant infection experiment with Atlantic salmon, Salmo salar L., smolt. Aeromonas salmonicida was detected in the water samples only until the intraperitoneally infected smolt were dead and had been removed. In the lipid rich surface microlayer, A. salmonicida was detected in high concentrations from the day of the first fish mortality and throughout the rest of the experiment. The significance of the high cell surface hydrophobicity is discussed as a possible reason for enrichment of A. salmonicida at the air-water interface. 相似文献
82.
Effects of epidural xylazine on EEG responses to surgical stimulation during isoflurane anaesthesia in dogs 总被引:1,自引:0,他引:1
K. A. Otto S. Piepenbrock B. Rischke C. Bötel† 《Veterinary anaesthesia and analgesia》1997,24(1):33-38
The effects of epidural administration of 250 μg/kg xylazine on EEG responses to surgical stimulation of 5 different intensities were evaluated during isoflurane anaesthesia for an experimental orthopaedic procedure in dogs. The dogs were assigned randomly to one of 2 treatment groups receiving either xylazine (n = 4) or equal volumes of sterile water (n = 4) (control group) epidurally. Intense surgical stimulation during removal of a bone graft from the dorsoiliac spine of the ileum was associated with a significantly (P = 0.0339) higher increase in EEG alpha/delta ratio after epidural administration of sterile water than after epidural injection of 250 μg/kg of xylazine. In addition, the preincision baseline values for 80% spectral edge frequency were significantly (P = 0.0339) lower in the xylazine group compared to control dogs. Our results suggest that epidural administration of 250 μg/kg of xylazine during orthopaedic procedures in dogs exerts antinociceptive effects which may be in part mediated by a supraspinal effect of xylazine. 相似文献
83.
A selected group of pharmaceutical compounds were evaluated for the ability to inhibit the biochemical activity of fibrinoligase (coagulation factor XIIIa*) in pooled equine plasma. Criteria for the pharmaceuticals selected were based on the mechanism of the transglutamination biochemical reaction mediated by coagulation factor XIIa*. These criteria were complemented by recognition of the molecular configuration and chemical composition of amino acid residue side chains involved in the process of covalent fibrin monomer polymerization (cross-linking, transglutamination) mediated by this enzyme. Each pharmaceutical was evaluated individually and in combination with other potential coagulation factor XIIIa* inhibitors in an effort to detect additive and synergistic phenomenon. In this context, pharmaceuticals with a carbonylamide (eg, cefuroxime, Girard's reagent-P, prolinamide) were applied in concert with compounds with a terminal amine (eg, D-arginine, L-lysine) functional group. In concept, this method theoretically served to competitively simulate glutamine and lysine amino acid residues within strands of fibrin monomer substrate involved in phase I (carbonylamide) and phase II (terminal amine) of the transglutamination reaction (covalent fibrin monomer cross-linking). Halogen-dinitro and ethylene compounds were also evaluated because of their reported ability to inactivate enzyme systems dependent on an intact sulfhydryl group located at their biochemically active site (eg, cystine amino acid residue). This group of pharmaceutical compounds failed to inhibit the biochemical activity mediated by coagulation factor XIIIa* in equine plasma. 相似文献
84.
Two outbreaks of the egg drop syndrome were observed in quail flocks maintained on a farm together with chickens. The decrease in egg production ranged from 10.6 per cent to 50.6 per cent, and the number of soft-shelled eggs increased with the decline in egg production. In both the outbreaks haemagglutination inhibiting antibodies to EDS-76 virus were detected. Fluorescent viral antigen specific to EDS-76 virus was also detected in the lining epithelial and glandular cells of the uterus. 相似文献
85.
Water-stable macro-aggregate size fractions (>2.0 mm, 1.0–2.0 mm, 0.5–1.0 mm and 0.25–0.5 mm) and non-aggregated soil from a sandy loam under long-term clover-based pasture and from grass pasture were analysed to determine the role of acid- and water-extractable carbohydrate C, total hyphal length, microbial biomass, organic C and total and mycorrhizal root length in stabilization of the aggregates. Aggregates were examined by scanning electron microscopy (SEM) and the particle-size distribution of the size fractions was also determined. Macro-aggregation increased under grass, relative to clover-based pasture; however, the properties of the aggregate fractions measured did not reflect this difference. Microbial-biomass C, extractable-carbohydrate C, hyphal length, total and mycorrhizal root length and organic C content of the soils were poorly correlated with macro-aggregation. Within the aggregates, the proportion of 250–1000-km sand was smaller and clay, silt and fine sand (20–250 μm) were greater relative to non-aggregated soil, suggesting that the >250-μm sand in the non-aggregated soil limited the stabilization of macro-aggregates. Under SEM, no enmeshment of aggregates by hyphae and roots was apparent. Although 50–160 m hyphae g?1 soil was found within the aggregates, calculations showed that on average only 5 to 13 lengths of hyphae were associated with each 250-μm cube of soil within the aggregates, and suggested little potential to stabilize the aggregates by enmeshing. On average, all >2.0-mm aggregates contained less than 3.6 mm of roots and less than 50% by weight of <2.0-mm aggregates contained a single length of root. The findings cast doubt about the role of hyphae and fine roots in the stabilization of macro-aggregates through an enmeshing mechanism in sandy soils. 相似文献
86.
K Adachi A Yoshimoto T Hasegawa T Shimizu Y Goto S Makimura 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1992,54(6):1081-1084
Due to the potential for anti-erythrocyte membrane antibodies as possible enhancers of erythrocyte destruction, the presence of serum anti-erythrocyte membrane antibodies in 31 dogs with Babesia gibsoni infection admitted to a veterinary hospital was investigated by an enzyme linked immunosorbent assay (ELISA) and immunoblotting analyses. This infection resulted in an increase of anti-erythrocyte membrane antibodies in 84% (IgG) and 74% (IgM) of 31 infected dogs, respectively. This was confirmed by the similarity in the protein profiles of the erythrocyte membrane antigens immunoblotted with rabbit antiserum to dog erythrocyte membrane antigens and infected dog serum. These results suggest the production of anti-erythrocyte membrane antibodies was induced by B. gibsoni infection. 相似文献
87.
K G Braund H S Steinberg A Shores J E Steiss J R Mehta M Toivio-Kinnucan K A Amling 《Journal of the American Veterinary Medical Association》1989,194(12):1735-1740
Six dogs with laryngeal paralysis had clinical, electrophysiologic, and pathologic evidence of a more generalized polyneuropathy. Three of the dogs were young Dalmatians, one was a young Bouvier des Flandres, and two were older, large-breed dogs. The results of this study suggest that laryngeal paralysis in dogs may frequently be one clinical sign of an underlying, more generalized polyneuropathy. Two forms of this generalized polyneuropathy may exist: an early form, as seen in young dogs with congenital or hereditary disease, and a delayed-onset form that is usually found in older dogs with so-called idiopathic laryngeal paralysis, some of which may have hypothyroidism. 相似文献
88.
Pharmacokinetics of enrofloxacin and its metabolite ciprofloxacin after intravenous and oral administration of enrofloxacin in dogs 总被引:9,自引:0,他引:9
K. KÜNG J.-L. RIOND M. WANNER 《Journal of veterinary pharmacology and therapeutics》1993,16(4):462-468
Rung, K., Riond, J.-L. & Wanner, M. Pharmacokinetics of enrofloxacin and its metabolite ciprofloxacin after intravenous and oral administration of enrofloxacin in dogs. J. vet
Four dogs were given 5 mg/kg body weight enrofloxacin intravenously (i.v.) and orally (p.o.) in a cross-over study. Plasma concentrations of the active ingredient enrofloxacin and its main metabolite ciprofloxacin were determined by a reversed phase liquid chromatographic method. Pharmacokinetic parameters of both substances were calculated by use of statistical moments and were compared to those of enrofloxacin described in the veterinary literature. Mean enrofloxacin t½λZ was 2.4 h, mean Cls was 27.1 ml/min-kg, and mean Vss was 7.0 1/kg. After i.v. and p.o. administration, concentrations of ciprofloxacin exceeding minimal inhibitory concentrations of several microorganisms were reached (Cmax = 0.2 ng/ml, max = 2.2 h after intravenous administration; Cmax = 0.2 (ig/ml, t max = 3.6 h after oral administration). A considerable part of the antimicrobial activity is due to ciprofloxacin, the main metabolite of enrofloxacin. 相似文献
Four dogs were given 5 mg/kg body weight enrofloxacin intravenously (i.v.) and orally (p.o.) in a cross-over study. Plasma concentrations of the active ingredient enrofloxacin and its main metabolite ciprofloxacin were determined by a reversed phase liquid chromatographic method. Pharmacokinetic parameters of both substances were calculated by use of statistical moments and were compared to those of enrofloxacin described in the veterinary literature. Mean enrofloxacin t
89.
90.
Agerholm, J.S., A. Basse and K. Christensen: Investigations on the occurrence of hereditary diseases in the Danish cattle population 1989-1991. Acta vet. scand. 1993, 34, 245-253.– The methods of the Danish Bovine Genetic Disease Programme are outlined, and the results obtained during the first 3 years in function are described. The most common disease reported was spinal muscular atrophy in calves of the Red Danish Dairy breed with 312 reports. Necropsy was performed on 162 cases, and spinal muscular atrophy was diagnosed in 82 of these. Bovine progressive degenerative mye-loencephalopathy, rectovaginal constriction, syndrome of arthrogryposis and palatoschisis, hereditary chondrodysplasia (2 different types), syndactylism, epitheliogenesis imperfecta, and osteogenesis imperfecta was diagnosed with 1 case each. Lethal trait A46 was diagnosed in 4 calves. Some of these diseases have not previously been described in Denmark, and epitheliogenesis imperfecta was for the first time diagnosed in the Hereford breed. Chromosome translocation 1/29 was detected in the Blonde d’Aquitaine (BAQ), Limousine, and Red Danish Dairy breed. The aberration occurred frequently in BAQ. Furthermore, a complex chromosome translocation t(l;8;9)(q45;ql3;q26) was detected in the Red Danish Dairy breed. 相似文献