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71.
The behavior of the sick animal is not necessarily a result of physical debilitation; it can be viewed as part of a highly organized adaptive strategy that is at times critical to survival if the animal were living in the wild state. Domestic ruminants appear to have retained this behavioral mode when they are sick. This article brings together several lines of current research about depression, appetite control, and the role of fever in facilitating an animal's ability to combat viral and bacterial infections.  相似文献   
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Objectives To assess a method for monitoring depth of anaesthesia using components of middle latency auditory evoked potential (AEP) waveforms during anaesthesia with fentanyl/fluanisone and midazolam. Study design Prospective observational study. Animals Five female Wistar rats weighing between 210 and 250 g. Methods Implanted electrodes were used to record AEPs in animals receiving five doses of anaesthetic. Recordings were made at 5 minutes post‐injection (deep anaesthesia; no pedal withdrawal response, PWR) and then at 25 minutes (light anaesthesia; strong PWR). Responses showed five characteristic peaks occurring at 11, 14, 23, 42 and 68 ms that were measured for latency of occurrence and peak amplitude. Results Auditory evoked potential peaks P14, N23 and P42 were increased significantly in latency with successive anaesthetic injections [avg. F(1,4) = 12.53, p < 0.001; avg. F(1,4) = 10.6, p < 0.001; avg. F(1,4) = 3.9, p = 0.02, respectively]. Peak N23 showed a significant reduction in latency during the 20 minute recovery period following both the first and second anaesthetic injections (t(3) = 7.52, p = 0.005; t(4) = 5.17, p = 0.007, respectively). Peak P42 occurred significantly earlier 20 minutes following the second anaesthetic injection (t(4) = 4.75, p = 0.009). The mean overall depth of anaesthesia assessed using PWR scores was significantly correlated with the mean latency of peak N23, such that as the strength of PWR increased, N23 occurred significantly earlier (r = ?0.99, p = 0.01). The amplitude difference between peaks N23 and P42 increased after the second and third drug administrations [avg. F(1,4) = 10.65, p = 0.031 and avg. F(1,4) = 11.24, p = 0.028, respectively]. Conclusion The characteristics of these peaks, and in particular latency of peak N23, may provide a useful tool for assessing depth of anaesthesia produced by this, and possibly other anaesthetic agents.  相似文献   
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A probabilistic model was developed to estimate target and non-target avian mortality associated with the application of the avicide CPTH (3-chloro-p-toluidine hydrochloride) to minimize sprouting rice damage in the southern USA. CPTH exposures for individual birds were predicted by random sampling from species-specific non-parametric distributions of bait seed consumption and CPTH residues detected on individual bait seeds. Mortality was predicted from the species-specific exposure versus mortality relationship. Individual variations in this response were captured in the model by Monte Carlo sampling from species-specific distributions of slopes and median toxicity values (LD50) for each bird. The model was used to simultaneously predict mortality (percentage of exposed population and number of birds killed/weight of consumed bait) for a target (blackbird) and non-target (mourning dove) species feeding on bait sites for up to five consecutive days.  相似文献   
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The objective of this study was to evaluate the safety and efficacy of a purified porcine insulin zinc suspension for treating dogs with uncomplicated diabetes mellitus. Fifty-three dogs were treated for 60 days after an initial dose determination period. The means of the blood glucose concentrations during 12-hour glucose curves and the means of the blood glucose nadir concentrations during 12-hour glucose curves for all dogs were determined before beginning insulin therapy (time 0), at the end of the dose determination period (time 1), 30 days after time 1 (time 2), and 60 days after time 1 (time 3). Presence of polyuria, polydipsia, and ketonuria was determined at each time point. Adequacy of control of hyperglycemia was based on 12-hour blood glucose curves and improvement in clinical variables (results of physical examinations, historic information, polyuria, polydipsia, and ketonuria). Safety was evaluated by questionnaire, performance of physical examination, CBC, serum chemistry profile, and urinalysis. The means of the blood glucose concentrations during 12-hour glucose curves and the means of the blood glucose nadir concentrations during 12-hour glucose curves for all dogs at times 1, 2, and 3 were significantly lower compared with time 0 (P < .0001). There was a reduction in the proportion of dogs with polyuria, polydipsia, and ketonuria of 82, 86, and 80%, respectively. All of the dogs had adequate glycemic control at time 1, 66% at time 2, and 75% at time 3. At time 3, 66% of dogs required insulin injections q12h. Other than hypoglycemia, there were no important adverse effects of insulin administration. The insulin, was safe and efficacious for reducing blood glucose and clinical signs in dogs with diabetes mellitus.  相似文献   
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The most common treatment for urine spraying and marking in cats has been administration of long-acting progestins. Treatment with diazepam has recently been gaining favor, particularly because of reported adverse effects of progestins. Results of a clinical trial involving 20 cats indicated that diazepam was effective in eliminating or markedly reducing spraying in 11 (55%) of them. However, most cats required continuous treatment, or at least intermittent treatment, when spraying recurred. The physiologic and behavioral dependency of cats on diazepam, which presumably develops over the course of administration, may contribute to the tendency for spraying to recur once diazepam treatment is discontinued. Using data from previously published findings on progestin administration, plus additional cases, it was documented that a significantly (P less than 0.05) higher percentage of males than females responded favorably. Although the number of cases was not sufficient for a statistical comparison of diazepam vs progestin treatment with regard to male vs female, possible gender difference in the effectiveness of diazepam was not indicated.  相似文献   
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A 5-week-old Fell Pony colt was examined for fever, lethargy, and anemia. The colt had been lethargic for 1 week before examination, had continued to nurse, had a temperature of 104°F (40°C), and was treated with ceftiofur (5 mg/kg IM q12h). Approximately 36 hours before examination, the colt developed watery diarrhea. Blood work performed by the referring veterinarian on the day of admission revealed a PCV of 10%.  相似文献   
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A 12-day-old Standardbred filly foal was presented with an acute onset hindlimb lameness of 24 hours duration. Initial ultrasonographic evaluation of the right gluteal region revealed oedematous change to the muscle architecture. Conservative therapy consisting of antimicrobials and stall rest was initiated. Forty-eight hours after admission a localised gluteal pyomyositis had developed. This was drained twice by percutaneous aspiration. Four days after admission the foal was euthanased. Necropsy examination revealed a septic proximal femoral physis with no grossly apparent joint involvement.  相似文献   
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