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The purpose of this study was to assess quantitative electroencephalography (q-EEG) in 10 healthy beagle dogs under propofol anaesthesia in order to determine objective guidelines for diagnostic electroencephalographic (EEG) recordings and interpretation. The basic pattern after preliminary visual examination of EEG recordings was characterized by spindles, k-complexes, vertex sharp transients, and positive occipital transients that were superimposed on the slow background activity. The results of the q-EEG were characterized by the prevalence of slow rhythms delta and theta, both in absolute and relative power spectrum analysis, while fast rhythms (alpha and beta) were poorly represented. The distribution of single frequency bands was widespread for delta, focal for frontal and central for theta, as well as for most alpha and beta patterns. The present study has shown that the use of quantitative EEG gives information on the frequency content of the bio-electrical activity and defines the distribution of the single frequency bands under a standardized anaesthetic protocol.

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In today's society small rodents and rabbits are increasingly kept as pets. Anaesthesia is necessary for numerous reasons and proves to be a challenge for many veterinarians. Following surgical intervention analgesia is frequently neglected. This article reviews the preparation of small mammals for anaesthesia, the choice of anaesthetics and the possibilities of perioperative care including monitoring, complications, fluid therapy and analgesia.

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Increasing is the number of Llamas (Llama glama) referred to veterinarians for diagnostic or therapeutic procedures which frequently require sedation or anaesthesia. Much of the knowledge concerning sedation and anaesthesia of domesticated ruminants and horses can be applied to sedate or anaesthetise a llama. A variety of considerations remain special for the llama. The article reviews all aspects of today's knowledge about sedation and anaesthesia of llamas.

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The anaesthetic effect of carbon dioxide (CO2) was investigated under predetermined exposure times in rats, mice and guinea pigs with admixture of 20% of oxygen (O2), and with 20% of ambient air in rats. In rats first symptoms (median) were detectable between 7 and 9.5 s, the induction time (median) varied between 16 and 20.5 s and the surgical tolerance (median) was 40 s (after 60 s of exposure) and 53.5 s (after 120 s of exposure) to 80% CO2/20% O2. When O2 was replaced by ambient air, a surgical tolerance of 53.5 s (after 60 s of exposure) and 77 s (after 120 s of exposure) was measured. In mice the induction time to 80% CO2/20% O2 was 10 s and the surgical tolerance 19.5 s (after 120 s of exposure). Guinea pigs showed an induction period of 20 s and a surgical tolerance of 50 s (after 30 s of exposure) to 80% CO2/O2. Recovery was short and smooth in all species. This method of general anaesthesia seems to be suitable for short and painful interventions, mainly in rats, but also in guinea pigs.

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Three cats affected with dystrophin deficiency and hypertrophic muscular dystrophy developed peracute rhabdomyolysis with a fatal outcome. Two cats were anesthetized with isoflurane for routine procedures and did not recover properly from the anesthetic procedure. One cat was manually restrained for an echographic examination and started staggering after a short struggle; its condition worsened, and it died. Blood chemistry findings included severe hyperkalemia, hyperphosphatemia, hypocalcemia, massive increases in creatine kinase, aspartate aminotransferase, and alanine aminotransferase concentrations, and high ion gap metabolic acidosis. Light microscopic evaluation of skeletal muscle revealed severe acute rhabdomyolysis with marked extensive necrosis of large groups of fibers and endomysial edema. These lesions were observed in many skeletal muscles but particularly in the masseter and supraspinatus muscles and in the diaphragm. Typical changes associated with dystrophin deficiency in cats were also noted. Histochemical analysis revealed that the dystrophin deficiency was associated with a decrease in the percentage of type 1 myofibers in all three cats. This change was marked in the 20-month-old cat and milder in the younger cats (6.5 and 8.5 months of age). Percentages of type 2A fibers were markedly decreased and percentages of type 2X fibers were markedly increased in the younger cats. Rhabdomyolysis has been reported in dystrophinopathic humans but not in other animal models of dystrophin deficiency. An increased sensitivity of the dystrophin-deficient sarcolemmal membrane to volatile anesthetic agents, stress, or intense muscular activity is suspected.

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The teeth of five adult captive brown bears (Ursus arctos ssp.) were examined and radiographed for occlusion, loss of teeth, dental plaque and calculus, and attrition under general anesthesia. Deposits of dental calculus were found in various locations with an overall prevalence of 8% to 15% of all tooth surfaces. In all five animals, severe enamel and dentinal attrition defects were observed in canine teeth with exposed pulp. Cage-chewing behavior is probably the main cause for the dental attrition. The composition of the food and feeding management are most likely responsible for the lack of natural cleaning and the resulting plaque and calculus formation. All affected canine teeth were treated with endodontic procedures using several materials and techniques, and evaluated one- to two-and-a-half years later by clinical examination, radiography, and scanning electron microscopy of silicone casts of the treated teeth. All coronal fillings were tight. The apices were not completely sealed in two teeth. We conclude that the use of adequate and specialized instrumentation and techniques for the treatment of these long, curved, large diameter root canals is more important than the particular endodontic and restorative materials used. The dental health status of zoo animals is an indicator of their general well-being. Preventive measures should be taken in their environment and management to minimize the risk of dental conditions.

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Cells of henbane (Hyoscyamus muticus L.) grow indefinitely in culture without exogenous auxin. Cells of its temperature-sensitive variant XIIB2 grow like the wild type at 26[deg]C but die rapidly at 33[deg]C unless auxin is added to the medium. Despite this temperature-sensitive auxin auxotrophy, XIIB2 produces wild-type amounts of indole-3-acetic acid (IAA). IAA is the predominant auxin and is important for plant growth and development. Since the IAA production of the variant is functional, we investigated whether the synthesis or degradation of IAA metabolites, possibly active auxins themselves, is altered. The IAA metabolites were IAA-aspartate (IAAsp) and IAA-glucose. The wild type converted IAA mainly to IAAsp, whereas the variant produced mainly IAA-glucose. Exogenous auxin corrected the shunted IAA metabolism of the variant. The half-life of labeled IAAsp in the variant was reduced 21-fold, but in the presence of exogenous auxin it was not different from the wild type. The temperature sensitivity of XIIB2 was also corrected by supplying IAAsp. Pulse-chase experiments revealed that henbane rapidly metabolizes IAAsp to compounds not identical to IAA. The data show that the variant XIIB2 is a useful tool to study the function of IAA conjugates to challenge the popular hypothesis that IAA conjugates are merely slow-release storage forms of IAA.

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The present research study had two goals. Firstly, the effect of medetomidine/propofol on the electroencephalographic (EEG) recordings of nine SPF dogs was analysed. It was found that the basic pooled pattern of EEG recordings was characterized by a mean amplitude of 28 uV (range = 15-70 uV) and mean frequency of 1.8 Hz (range = 1-2.5 Hz), with superimposed low voltage (amplitude range = 4-20 uV; mean 14 uV) and fast activity (frequency range = 10-27 Hz; mean 18 Hz). All results were significantly constant (P < 0.05) and accurately reproducible (R = 0.70). The second goal was to investigate the value of EEG findings from dogs experimentally infected with canine distemper virus (CDV) under the same anaesthetic conditions, for the diagnosis of encephalitis. It was found that the EEG traces were characterized by high voltage, slow activity (HVSA) with superimposed low voltage, fast activity (LVFA). By comparing the mean values of amplitude and frequency for each single phase at different time intervals, it was found that only the mean value of the superimposed frequency was linearly distributed and changed significantly (P < 0.001). Thus, at least three readings should be taken from phase III of the EEG recording in order to obtain accurate values. The study has shown that electroencephalography can supply valuable information in cases of CDV encephalitis and can assist greatly in the differential diagnosis.

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Laboratory testing in 10 "Walliser Schwarzhals"-goats included red and white blood cell count, electrolytes, liver enzymes, trace elements and urinalysis, protein determination and cell count of the cerebrospinal fluid (CSF) was also performed. Electrodiagnostic testing included electromyography (EMG) of the head and spinal muscles, motor nerve conduction velocity (MNCV) of the right and left peroneal nerve, brainstem auditory evoked potentials (BAEP) and electroencephalography (EEG). MNCV of the peroneal nerve was 72 +/- 9.24 m/s. Latency and amplitude of the BAEP for P1 was 2.15 +/- 0.08 ms respectively 2.23 +/- 0.7 microV and for P5 5.09 +/- 0.15 ms respectively 0.68 +/- 0.24 microV. P2 (3.2 +/- 0.14 ms/1.37 +/- 0.32 microV) and P3 (3.9 +/- 0.13 ms/0.84 +/- 0.14 microV) were equally distributed between P1 and P5. Whereas the results of EMG and BAEP were similar to those of other species, the electroencephalographic findings consisted of three different patterns depending on duration and depth of isofluran anesthesia. Pattern I had a rhythmic high amplitude (80 microV) and low frequency (1-2 Hz) pattern with aperiodic intervals of relative electric silence. Pattern II was characterized by increased duration of HALF (150 microV), associated with spindles of low amplitude (20-30 microV) and high frequency (10 Hz). Pattern III had generalized delta-activity of high amplitude (70-200 microV). All the results are discussed briefly.

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A specific, sensitive, reverse-phase high-performance liquid chromatographic assay for acepromazine, with analytic sensitivity as low as 5 ng/ml of plasma, and electrochemical detection with an oxidation potential of 0.7 V, was used to study the pharmacokinetics of acepromazine given at a dosage of 0.15 mg/kg of body weight in horses. The relation between effect and pharmacokinetics of the drug was examined. The effects studied included those on blood pressure, pulse, PCV, measures of respiration function, and sedation. Intravenously administered doses led to a biphasic concentration decay pattern with an alpha-phase distribution half-life of < 3 minutes. The beta-phase half-life was in the range of 50 to 150 minutes. The CNS effects peaked at 20 minutes after administration, and the hemodynamic effects peaked at 100 minutes. In all horses, the most sensitive variable was the PCV, which decreased by up to 20% (P < 0.0001). Systolic, diastolic, and mean blood pressures decreased (P < 0.0001); heart rate was unchanged (P > 0.05). Neither blood gas tensions nor blood pH changed noticeably (P > 0.05). In all horses studied, acepromazine had a significant (P < 0.0001) sedative effect, as observed by posture and alertness. None of the observed pharmacodynamic effects correlated well with plasma acepromazine concentration. These effects persisted beyond the time of detectable acepromazine concentration, indicating that they might be caused by active metabolites, or that their timing could result from complex pharmacokinetic compartment influences.

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Propofol was evaluated as an intravenous agent for induction of anesthesia in 94 non-premedicated New Zealand White rabbits (mean body weight 3.25 kg). Lack of chewing oral introduction of an endotracheal tube was chosen as the end-point in signaling loss of consciousness. A rapid and excitement-free loss of consciousness was observed. Using probit analysis, a 50% effective dose of 6.44 mg/kg was calculated. No statistically significant difference between genders was shown. Independent of the dose administered, recovery was rapid and smooth.

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The cardiopulmonary effects of propofol as the sole anesthetic agent administered as a continuous intravenous infusion over 8 hours were evaluated in ten ventilated New Zealand White rabbits. Heart rate, mean blood pressure, arterial oxygen and carbon dioxide tensions, arterial pH, hemoglobin's saturation with oxygen, packed cell volume, and temperature were continuously monitored and recorded at 0 (baseline), 30, 60, 120, 180, 240, 300, 360, 420, and 480 minutes and then hourly for up to 4 hours during recovery. Only light planes of anesthesia could be achieved with a mean propofol infusion rate of 0.876 mg/kg/min. Hypotension and hypoxemia were common features. Four rabbits did not survive the study period and recovery was slow in the surviving animals. With monitoring being the same, Intralipid 10%, the vehicle of propofol, infused into two rabbits (controls) had no adverse effects. Intravenous administration of propofol alone cannot be recommended for long-term anesthesia in the rabbit. Oxygen supplementation appears to be an important element in improving quality of anesthesia and outcome.

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