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Objective To investigate the distribution and prevalence of mucormycosis in platypus (Ornithorhynchus anatinus) from the Inglis, Emu and Black-Detention catchment areas in north-west Tasmania. Procedure A field study was performed and resulted in the examination of 44 wild platypuses; in addition, one dead platypus and two live platypuses were examined after they were independently submitted to a local veterinary clinic. Results No cases of mucormycosis were conclusively diagnosed. One platypus with signs consistent with those previously described in cases of mucormycosis was captured in the Emu River catchment. However, laboratory tests did not provide a definitive diagnosis for the lesion. Two platypuses from the Inglis catchment area had signs very similar to those previously described in cases of mucormycosis, but laboratory tests found Corynebacterium ulcerans to be the likely cause of the cutaneous ulcers on one of these platypuses and an unidentified fungal agent to be the cause of a cutaneous nodule in the other. Conclusions These findings do not prove that mucormycosis is absent from the populations studied. However, they may indicate that the prevalence of disease is low. The possibility that Mucor amphibiorum is present in a subclinical form in platypuses, or infecting another reservoir, is not excluded. The findings also suggest that caution should be exercised when diagnosing mucormycosis based on clinical findings alone and raise the possibility that some cases may have been incorrectly diagnosed.  相似文献   
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Ketamine is a rapid acting, potent, nonspecific, noncompetitive N-methyl-D-aspartate (NMDA) receptor antagonist commonly used for inducing general anesthesia and for providing post-operative pain management and may possibly lessen the need for other potentially harmful or contraindicated analgesics in camelids, such as nonsteroidal anti-inflammatory drugs. Prior to determining the effectiveness of CRI ketamine for analgesia, a safe, sub-anesthetic dose was established that did not produce untoward side effects, sedation or alter normal behavior. Six healthy male alpacas (40–90 kg) were used for the trial and each acted as its own control. Each alpaca was randomly assigned to receive ketamine at 20 and 40 μg kg–1 minute–1 in 500 mL saline. A blinded observer recorded heart rate, respiratory rate, and body temperature hourly, and behavior for 8 hours. There was a 72-hour washout period between each dosing regime. An equal volume saline CRI without ketamine was used as a control. Each alpaca was allowed a one-week washout prior to being anesthetized with isoflurane using mask induction. After achieving a stable plane of anesthesia, the MAC value for isoflurane was determined. Ketamine was infused at 40 μg kg–1pre-existing pain is unknown, but for elective procedures, preemptive analgesia using ketamine CRI in alpacas may be beneficial.  相似文献   
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进行了头孢拉定对母猪产后肺炎混合感染的疗效试验,并设对照组进行比较.结果:静脉注射头孢拉定组治愈率、死亡率、仔猪发病率、仔猪成活率、仔猪断奶体质量分别为86.67%、0、12.5%、90.5%和6.3 kg;统计学分析结果显示,静脉注射头孢拉定组的治愈率、仔猪成活率和仔猪断奶重显著高于对照组(P<0.01),死亡率、仔猪发病率明显低于对照组(P<0.01),疗效显著.  相似文献   
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We report on a wind-tunnel study with 1 : 75 scale model treesdesigned to examine the influence of canopy structure on theformation of turbulent gusts above forests. This was to testthe hypothesis that more irregular canopy structures produceless intense gusts because the change in wind speed with heightat canopy top is less severe. Measurements were made of windspeeds and turbulence within and above the model forests andof the wind loading on model trees in four different silviculturalsystems. The systems tested were even-aged, single-tree selection,shelterwood/group selection and strip felling. The measurementsshowed that the profiles of different mean wind and turbulencecharacteristics above the forests are remarkably similar whenvertical heights are normalized by the height of the tallesttree but differences do exist within the canopy. The wind loadingmeasurements indicated no difference between the systems interms of stability except possibly for the shelterwood/groupselection. In the shelterwood/group selection system the presenceof smaller sub-canopy trees appears to reduce the loading onthe main canopy trees either by providing support and increasingdamping or by absorption of energy from the canopy-penetratinggusts.  相似文献   
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This study evaluated the structural changes in the reproductive tract of Asiatic black bears using serial transrectal ultrasonography. In addition, the ultrasonographic observations were compared with the results of vaginal cytology and hormonal analyses. The collection of blood for hormonal analysis, vaginal cytology and transrectal ultrasonography was performed in two bears (Bears 1 and 2) from June 2011 to August 2013 without mating and in a third bear (Bear 3) from April to December 2012, allowing natural mating. Serial ultrasonographic observations showed cyclic changes in ovarian structures (e.g. emergence of small follicles, growth and ovulation of dominant follicles and corpus luteum (CL) formation) during the reproductive cycles of the three bears. The diameter of the uterine horns remained similar throughout the reproductive cycle in Bears 1 and 2, and it remained similar from April until October, but an enlargement containing foetuses was observed in Bear 3 in December. The ultrasonographic observations were consistent with the data obtained through vaginal cytology and progesterone analysis during the reproductive cycle. An average of 4.0 (±0.4) dominant follicles was observed during the oestrous stage (May‐August), during which the superficial cells accounted for >90% of the total vaginal cells. In addition, the detection of an average of 2.6 (±0.2) CL was associated with increased plasma progesterone concentrations (3.0 ± 0.4 ng/ml) between June and December (near hibernation). In conclusion, serial transrectal ultrasonography demonstrated yearly oestrous (ovulation) cycles via follicular dynamics and CL formation on ovaries, accordingly with vaginal cytology and hormonal level in the Asiatic black bear.  相似文献   
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Helioseismology is probing the interior structure and dynamics of the sun with ever-increasing precision, providing a well-calibrated laboratory in which physical processes can be studied under conditions that are unattainable on Earth. Nearly 10 million resonant modes of oscillation are observable in the solar atmosphere, and their frequencies need to be known with great accuracy in order to gauge the sun's interior. The advent of nearly continuous imaged observations from the complementary ground-based Global Oscillation Network Group (GONG) observatories and the space-based Solar and Heliospheric Observatory instruments augurs a new era of discovery. The flow of early results from GONG resolves some issues and raises a number of theoretical questions whose answers are required for understanding how a seemingly ordinary star actually operates.  相似文献   
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