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371.
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Same‐day mass sterilization of feral cats requires rapid onset, short‐duration anesthesia. The purpose of this study was to compare our current anesthetic protocol, Telazol–ketamine–xylazine (TKX) with medetomidine–ketamine–buprenorphine (MKB). Feral female cats received either IM TKX (n = 68; 0.25 mL cat?1; tiletamine 12.5 mg, zolazepam 12.5 mg, K 20 mg, and X 5 mg per 0.25 mL) or MKB (n = 17; M 40 µg kg?1, K 15 mg kg?1, and B 10 µg kg?1). Intervals measured included time from injection to recumbency, time to surgery, duration of surgery, and time from reversal of anesthesia (TKX: yohimbine 0.50 mg cat?1 IV; MKB: atipamezole 0.50 mg cat?1 IM) to sternal recumbency. Following instrumentation (Vet/Ox 4403 and Vet/BP Plus 6500), physiological measurements were recorded at 5‐minute intervals, and included rectal temperature, heart rate (HR), respiratory rate (RR), SpO2 (lingual or rectal probes), and indirect mean arterial blood pressure (MAP) (oscillometric method). Nonparametric means were compared using Mann–Whitney U‐tests. Parametric means were compared using a two‐factorial anova with Bonferroni's t‐tests. The alpha‐priori significance level was p < 0.05. Values were mean ± SD. Body weight (TKX: 2.9 ± 0.5 kg, MKB: 2.7 ± 0.7 kg), time to recumbency (TKX: 4 ± 1 minutes, MKB: 3 ± 1 minutes), time to surgery (TKX: 28 ± 7 minutes, MKB: 28 ± 5 minutes), and duration of surgery (TKX: 11 ± 7 minutes, MKB: 8 ± 5 minutes) did not differ between groups. In contrast, MKB cats required less time from reversal to sternal recumbency (TKX: 68 ± 41 minutes, MKB: 7 ± 2 minutes) and were recumbent for shorter duration (TKX: 114 ± 39 minutes, MKB: 53 ± 6 minutes). Temperature decreased during the study in both groups, but overall temperature was higher in MKB cats (38.0 ± 0.95 °C) than in TKX cats (37.5 ± 0.95 °C). RR, HR, and SpO2 did not change during the study in either group. However, overall HR and RR were higher in TKX cats (RR: 18 ± 8 breaths minute?1, HR: 153 ± 30 beats minute?1) compared to MKB cats (RR: 15 ± 7 breaths minute?1, HR: 128 ± 19 beats minute?1). In contrast, overall SpO2 was lower in the TKX group (90 ± 6%) compared to the MKB group (94 ± 4%). MAP was also lower in the TKX group (112 ± 29 mm Hg) compared to that in the MKB group (122 ± 20 mm Hg). However, MAP increased in the TKX group during surgery compared to pre‐surgical values, but did not change in the MKB group. The results of this study suggested that MKB might be more suitable as an anesthetic for the purpose of mass sterilization of feral female cats.  相似文献   
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The effect of a bacterial infection on interferon-alpha (IFN-alpha) and interleukin-6 (IL-6) production by porcine cells was studied in specific pathogen-free (SPF) pigs, infected intranasally with Actinobacillus pleuropneumoniae serotype 2. Three experimental groups of five pigs were used: infected non-treated pigs, infected pigs that were treated with enrofloxacin at disease onset, and non-infected, non-treated control pigs. Blood samples were collected from all pigs on the day of infection and on days 1, 4, 7, 13 and 17 post-infection. Sera were analysed for presence of antibodies to A. pleuropneumoniae and for the cytokines IL-6 and IFN-alpha. Ability to produce these cytokines was tested in vitro using whole blood cultures stimulated with inactivated virus (Aujeszky's disease virus infected porcine kidney cells (ADV/PK-15)), inactivated bacteria (A. pleuropneumoniae) or bacterial plasmid (pcDNA3). All cytokine inducers were used neat or pre-incubated with the transfectious agent lipofectin. IL-6 appeared in the serum of all infected non-treated animals but no IFN-alpha was found in the serum of any of the experimental pigs. Accordingly, the bacteria induced a substantial IL-6 but hardly any IFN-alpha production when tested in vitro. However, following incubation with lipofectin, the inactivated bacteria as well as pcDNA3 became efficient inducers of IFN-alpha in whole blood cultures. The increased IFN-alpha production, previously recorded in vitro during the acute phase of infection with A. pleuropneumoniae, was confirmed using lipofected plasmid DNA and it was indicated that leukocytes obtained from infected but apparently cured animals also exhibited an increased production of IFN-alpha. Thus, even mild/sub-clinical bacterial infections may affect cytokine production in pigs.  相似文献   
376.
BACKGROUND: There is considerable variation in the coagulation profile of dogs with disseminated intravascular coagulation (DIC), making it difficult to assess overall hemostatic function. OBJECTIVES: To characterize the overall hemostatic state in dogs with DIC, by use of tissue factor-activated thromboelastography (TF-TEG), and to determine whether there is an association between hemostasis and outcome. ANIMALS: 50 dogs with DIC. METHODS: Dogs admitted to the intensive care units, with an underlying disease known to predispose to DIC, were prospectively assessed with TF-TEG. Citrated blood samples were collected daily during hospitalization and an extended coagulation panel and TF-TEG were performed. Diagnosis of DIC was based on expert opinion. RESULTS: Hemostatic dysfunction was observed on the TF-TEG profile in 33/50 of the dogs, of which 22/50 were hypercoagulable and 11/50 were hypocoagulable based on the TF-TEG G value alone. There were significant differences in k, alpha, and MA values (P < .0001) among hypo-, normo-, and hypercoagulable dogs. There was a significant difference in case fatality rate between hypo- (64%) and hypercoagulable (32%) dogs (relative risk = 2.38; P= .04). Dogs that died had significantly lower antithrombin activity (P= .03) and higher d-dimer concentration (P= .03) than survivors. CONCLUSIONS: The most common overall hemostatic abnormality in dogs diagnosed with DIC was hypercoagulability, and there was significant difference in survival between hyper- and hypocoagulable dogs. The results suggest TF-TEG is valuable in the assessment of hemostatic function in dogs diagnosed with DIC.  相似文献   
377.

Objective

To investigate the clinical and physiological effects of intravenous (IV) alfaxalone alone or in combination with buprenorphine, butorphanol or tramadol premedication in marmosets.

Study design

Prospective, randomized, blinded, crossover design.

Animals

Nine healthy marmosets (391 ± 48 g, 3.7 ± 2.2 years old).

Methods

Meloxicam 0.20 mg kg?1 subcutaneously, atropine 0.05 mg kg?1 intramuscularly (IM) and either buprenorphine 20 μg kg?1 IM (BUP-A), butorphanol 0.2 mg kg?1 IM (BUT-A), tramadol 1.5 mg kg?1 IM (TRA-A) or no additional drug (control) were administered to all marmosets as premedication. After 1 hour, anaesthesia was induced with 16 mg kg?1 alfaxalone IV. All animals received all protocols. The order of protocol allocation was randomized with a minimum 28 day wash-out period. During anaesthesia, respiratory and pulse rates, rectal temperature, haemoglobin oxygen saturation, arterial blood pressure, palpebral and pedal withdrawal reflexes and degree of muscle relaxation were assessed and recorded every 5 minutes. Quality of induction and recovery were assessed. Duration of induction, immobilization and recovery were recorded. Blood samples were analysed for aspartate aminotransferase, creatine kinase and lactate dehydrogenase concentrations. The protocols were compared using paired t tests, Wilcoxon's signed-rank test with Bonferroni's corrections and linear mixed effect models where appropriate.

Results

Out of nine animals, apnoea was noted in eight animals administered protocol BUP-A and two animals administered protocol BUT-A. With TRA-A and control protocols, apnoea was not observed. No other significant differences in any of the parameters were found; however, low arterial blood pressures and hypoxia occurred in TRA-A.

Conclusions and clinical relevance

Our study employing different premedications suggests that the previously published dose of 16 mg kg?1 alfaxalone is too high when used with premedication because we found a high incidence of complications including apnoea (BUP-A), hypotension and hypoxaemia (TRA-A). Appropriate monitoring and countermeasures are recommended.  相似文献   
378.
Clostridium difficile is a common nosocomial pathogen in humans and animals that causes diarrhea and colitis following antibiotic therapy. Isolates of C. difficile obtained from faecal material from 20 human patients and 6 equine subjects with antibiotic-associated diarrhea were investigated regarding production of toxins A and B, their capacity to adhere to the human intestinal Caco-2 cell line and equine intestinal cells, and for the presence of fimbriae. The results showed that most (17/20) of the human clinical isolates produced both toxins A and B. One of the human isolates proved toxin A-negative/toxin B-positive. All (6/6) horse isolates were positive for both toxins A and B. Both the human and horse isolates possessed the capacity to adhere, to varying degree, to human and equine intestinal cells. It appeared that human isolates produced greater amounts of toxin B, and that there was a host-species dependency on ability to attach to intestinal epithelial cells. No fimbriae were found in any of the investigated isolates.  相似文献   
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The main aim of this study was to increase our knowledge on how fish farm effluents influences the surface water quality in the Åland archipelago (Baltic Sea). A second aim was to conduct critical model tests of three models that predicts the impact of farm emitted phosphorus on total phosphorus (TP), chlorophyll and Secchi depth. Extensive field studies were conducted between 1997 and 1999 in nine defined coastal areas with, and four reference areas without, fish farms. According to our results the most significant effects on TP concentrations, periphytic growth and phytoplankton standing crop was observed in two coastal bays with small to moderate fish farm production (≈70 tonnes per year). The significant effects in each bay was mainly due to the small size of the bay (0.48 and 0.73 km2) and the shallow mean water depth (3 and 3.8 m), rather than long water retention times (2 and 6 days). Due to a very large fish farm production (800 tonnes per year), we also observed significant effects in a coastal area of moderate size (8 km2), which had a theoretical water retention time of about 8 days. No significant effects of fish farm effluents on the surface water quality were observed in the other six areas. Furthermore, our data shows that, besides the fish farm effluents, the import of nutrients from the surrounding sea and the sediment resuspension may have a decisive effect on the water quality in the studied areas. Finally, we can conclude that at least two of the tested models are useful in context of environmental management.  相似文献   
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