Continuous lumbar hemilaminectomy for intervertebral disc disease in an Amur tiger (Panthera tigris altaica)

A 13-yr-old Amur tiger (Panthera tigris altaica) was presented for an acute onset of paraplegia. Spinal imaging that included plain radiographs, myelography, and computed tomography performed under general anesthesia revealed lateralized spinal cord compression at the intervertebral disc space L4-5 caused by intervertebral disc extrusion. This extrusion was accompanied by an extensive epidural hemorrhage from L3 to L6. Therefore, a continuous hemilaminectomy from L3 to L6 was performed, resulting in complete decompression of the spinal cord. The tiger was ambulatory again 10 days after the surgery. This case suggests that the potential benefit of complete spinal cord decompression may outweigh the risk of causing clinically significant spinal instability after extensive decompression.     

Bestimmung mikrobieller Biomasse im Boden: Eine kritische Betrachtung

Estimation of Microbial Biomass in Soil: A Critical View Unrepresentative factors have been applied to calculate microbial C in a wide range of soils without consideration of soil properties, physiological state of microbial populations, and experimental conditions. In this paper principal and technical difficulties of different methods to estimate microbial biomass in soils as well as interpretation of results are discussed. The author concludes, that a standard method to measure microbial C in a wide range of soils remains an elusive aim. Neither is there a need to convert microbial data into biomass, especially for many questions related to the role of microorganisms in soils (soil fertility, ecotoxicology, the influence of climatic factors, soil treatments and cultivation, etc.).     

Applicability of arginine ammonification as indicator of microbial activity in different soils

Summary Amendment of soils with arginine resulted in immediate liberation of ammonia. The rate was linear for several hours, and was strongly reduced by toluene treatment or under anaerobic conditions. Together with a strong stimulation of respiration by arginine these results demonstrate that arginine ammonification is due to living microorganisms. Arginine ammonification was strongly related to respiration and correlated significantly with the carbon content of the soil, but not or only poorly with soil pH, ammonia content, percentage clay or the number of microorganisms.     

Comparison of different applications of the sonographic contrast medium Levovist

The influence of the application modes (bolus injection, infusion) of the sonographic signal enhancers Levovist was investigated in a total of 24 dogs. The animals in the bolus group were given 0.2 ml/kg body mass Levovist at a concentration of 300 mg/ml while in the other group the same amount was continuously injected over a time of two minutes. Signal enhancement was measured by an audiodoppler. Contrast duration above six, twelve, 18 and 24 dB and maximum signal enhancement were determined for each application mode. The comparison of these parameters showed that a statistically significant longer contrast duration (significance level p less than 0,05) at 0 and 6 dB can be achieved by continuous injection. Bolus application, on the other hand, resulted in significantly higher maximum contrast enhancement. With time consuming investigations (perfusiondiagnostic, shuntdiagnostic) the contrast effect can be partly extended with continuous injection but the technical requirements are higher and there is the risk that the acoustic properties of the microbubbles are negatively influenced.     

Is routine pre-anaesthetic haematological and biochemical screening justified in dogs?

OBJECTIVES: To determine if routine haematological and biochemical screening is of benefit in dogs requiring anaesthesia and to establish the most useful tests for pre-anaesthetic risk assessment. ANIMALS: One thousand five hundred and thirty-seven client-owned dogs undergoing surgery at the University of Leipzig between January 2003 and April 2004. MATERIALS AND METHODS: After obtaining a standardized history and a physical examination, all dogs requiring anaesthesia were assigned to an ASA physical status group, their needs for pre-anaesthetic therapy determined and an anaesthetic protocol proposed. Haematological (haematocrit, red blood cell count, white blood cell count, platelet count and haemoglobin concentration) and serum biochemistry tests (plasma urea, creatinine, glucose, total protein, sodium and potassium concentration; serum alanine aminotransferase, alkaline phosphatase and lipase activity) were then performed in all animals. The results of these were then used to: 1) re-define each dog's ASA physical status; 2) determine any altered requirement for pre-anaesthetic therapy; 3) re-determine the suitability of the dog to undergo surgery; and 4) re-examine the suitability of the original proposed anaesthetic protocol. RESULTS: The history and clinical examination in 1293 out of 1537 dogs (84.1%) revealed that haematological and biochemical tests would have been considered unnecessary under normal conditions. Of these, 63.9% were categorized as ASA 1, 28.5% as ASA 2, and 7.6% at higher risk. In some dogs, screening tests showed abnormal results: 16.7% of 1293 dogs had abnormal plasma urea levels, with 5.9% of values above the reference range. However, only 104 dogs (8%) would have been re-categorized at a higher physical status category had the laboratory results been available. Additional screening data indicated that surgery would have been postponed in 10 dogs (0.8%) additional pre-anaesthetic therapy would have been provided in 19 animals (1.5%) and the anaesthetic protocol altered in two dogs (0.2%). CONCLUSION: The changes revealed by pre-operative screening were usually of little clinical relevance and did not prompt major changes to the anaesthetic technique. CLINICAL RELEVANCE: In dogs, pre-anaesthetic laboratory examination is unlikely to yield additional important information if no potential problems are identified in the history and on physical examination.     

Anesthesia of horses with xylazine and ketamine. 2. Anesthesia in adult horses

Xylazine and Ketamine were used for anaesthesia in 250 adult horses. This combination is useful both for induction and maintenance of anaesthesia. The induction with Xylazine and Ketamine has been successful not only with foals but also with high risk patients such as horses with colic. During the maintenance of anaesthesia Xylazine/Ketamine can be used with injectable anaesthetics as well as with volatile anaesthetics at the same time. A form of injection anaesthesia for short-time surgical procedures like castration and wound repair is presented. The maintenance of a Thiobarbiturate/Guaifenesin anaesthesia with Xylazine/Ketamine seems to be suitable for field conditions.     

Rapid and sensitive determination of microbial activity in soils and in soil aggregates by dimethylsulfoxide reduction

Summary Based on the reduction of dimethylusulfoxide (DMSO) to dimethylsulfide (DMS) by microorganisms, a simple, rapid, sensitive and inexpensive method for the determination of microbial activity in soil samples was developed. When DMSO was added to samples, DMS appeared immediately in the gas phase, which was quantitatively analyzed by gas chromatography. The DMS liberation rate was constant for several hours. The reaction immediately starts and its linearity indicate that neither the physiological state nor the number of organisms were changed by the assay. DMSO reduction is widespread among microorganisms; out of 144 strains tested (both fungi and bacteria) only 5 were unable to carry out this reaction. The reaction in soil samples was strongly inhibited by toluene, cyanide, azide, or by fumigation, but was considerably stimulated by glucose. These findings demonstrate that the reaction was due to the activity of microorganisms. The DMSO reduction in different soil samples was significantly correlated with arginine ammonification and heat output (r>0.9). A good correlation was observed with the organic-matter content (r = 0.74), but not with microbial numbers, clay content, or the pH of the soil. Standard deviations of less than 10% were routinely found. Furthermore, the method is sufficiently sensitive to allow measurements of activity in very small samples (< 0.1 g). For example, a microbial activity profile can be established for a single soil aggregate, revealing marked differences in activity on the outside and in the interior.