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41.
Objective To compare the postoperative analgesic and sedative properties of buprenorphine and morphine in cats. Study Design Prospective, randomized, blinded study. Animals Thirty‐two domestic cats undergoing surgery. Methods Cats received pre‐anaesthetic medication with acepromazine (0.05 mg kg?1) given intramuscularly and were randomly allocated to group M and given morphine (0.1 mg kg?1) intramuscularly (IM) or to group B and given buprenorphine (0.01 mg kg?1) IM. Anaesthesia was induced with propofol and maintained with halothane in oxygen and nitrous oxide. Pain and sedation scores using visual analogue scales, and heart and respiratory rates, were measured immediately before, and 30, 60, 120, 180, 300 and 420 minutes after anaesthesia. Results Pain scores were significantly lower at 60, 120 and 180 minutes after anaesthesia in group B. Group B also had higher heart rates at 30 minutes. There were no other statistically significant differences between the groups. Clinical relevance Buprenorphine (0.01 mg kg?1) appeared to provide better postoperative analgesia than morphine (0.1 mg kg?1) and may also have a longer duration of action.  相似文献   
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SUMMARY A decision analysis model was designed to evaluate the cost effectiveness of a vaccination program for preventing endemic or epidemic porcine parvovirus (PPV) Induced reproductive failure in a 100-sow pig herd. The results showed that the cost of vaccination was less than the cost incurred by continuing endemic PPV infection, or the cost of a severe epidemic. A long term vaccination program is a cost effective method for controlling PPV-induced reproductive failure in pig herds suffering endemic and epidemic PPV infection.  相似文献   
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During the summer of 1990 deaths, occurred in racing camels (Camelus dromedarius) associated with a specific disease syndrome. Clinical signs included pyrexia, coughing, lachrymation, oedema of the throat and submandibular region and enlargement of submandibular lymph nodes. In terminal cases nervous signs were present and sometimes there was bloody diarrhoea and vomiting. Of 480 camels at least 70 animals were affected with the disease and about 40 died. Morbidity and mortality was greater in camels recently imported. Consistent necropsy findings were extensive petechial and ecchymotic haemorrhage beneath the epicardium, endocardium and visceral pleura and in the mediastinal lymph nodes, and haemorrhagic oedema of the pharyngeal and laryngeal areas. Haemorrhages occurred more variably in abdominal organs and on the omasal and abomasal mucosa. Bronchopneumonia, omasitis and abomasitis were observed on microscopic examination, together with liver and kidney lesions of presumed toxic origin. Fungal hyphae and, occasionally, the characteristic conidial morphology of Aspergillus fumigatus were seen in sections and direct smears from lesions in the respiratory and alimentary tracts. A fumigatus was cultured from trachea, bronchi, bronchioles, lung tissue, heart blood, omasum, abomasum, ileum and submandibular lymph nodes. Whether the role of Aspergillus in the overall syndrome is primary or secondary has not been established; no other potential aetiological agent has been identified.  相似文献   
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Transmission of ovine herpesvirus-2 (OvHV-2) in sheep via natural contact and nasal secretions was examined. OvHV-2-free lambs were produced by separating newborn lambs from their mothers within 5 days of birth and raising them in an isolation facility. Transmission experiments via natural contact were conducted by keeping OvHV-2-free lambs with OvHV-2-infected sheep of different ages. Six of the infected ewes in this experiment were pregnant and gave birth during the experimental period. OvHV-2 was not transmitted from the adult sheep, though viral DNA was consistently detected in their peripheral blood leukocytes (PBL). On the other hand, OvHV-2 was transmitted from recently infected lambs to sheep at 10 or 12 weeks after the onset of contact. In addition, we attempted the experimental transmission of OvHV-2 via nasal secretions, by transferring nasal washings from infected sheep to the nostrils of uninfected sheep. Sheep receiving the nasal washings from infected adult sheep maintained their negative status for 15 months, whereas sheep receiving nasal washings from recently infected lambs acquired OvHV-2 by 8 months. The results of these experiments support that OvHV-2 is more easily transmitted to negative sheep by recently infected lambs than by adult sheep. Further, it is supposed that the nasal cavity is a portal for entry and shedding of infectious OvHV-2 in sheep.  相似文献   
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Observations were made on the abundance and survival of Haemonchus placei, Cooperia punctata and Oesophagostomum radiatum infective larvae from cattle faecal pats exposed at various times of the year in north Queensland wet tropics. Pats exposed in the hot, wet season yielded abundant larvae on herbage. In the dry season, although low numbers of infective larvae were usual, considerable numbers were produced under conditions of heavy dews on dense herbage. Irrespective of season of deposition of pats, the resulting larvae persisted generally for not longer than 10 to 12 weeks, and in large numbers for only 2 to 6 weeks. The findings suggest that prevention of contamination in the wet season, and in the dry season when light rainfalls are accompanied by heavy dews on dense herbage, will result in low levels of larval infestation on herbage. Rotational grazing in the area is suggested as a means of worm control.  相似文献   
48.
Irrigation development induces considerable environmental change, but the expectation has been in the past that the economic and social benefits would be greater than the environmental costs. However, public attitudes change over time from acceptance of development and exploitation to greater concern regarding environmental issues and sustainability. Recently, the irrigation industry has found it difficult to communicate to the wider populace the regional benefits of irrigation and the current activities and investment undertaken to address the environmental sustainability concerns. To address this, irrigation water supply businesses are investigating using a broader reporting structure that includes financial, environmental, and social and cultural elements. This triple bottom line, holistic approach should provide a more balanced view of water use with socio-economic benefits and environmental consequences demonstrated. It is anticipated that this approach embedded in the newly developed Irrigation Sustainability Assessment Framework will lead to a more transparent and informed debate on the sustainable use of resources between all parties.  相似文献   
49.
The population dynamics of Metapenaeus dobsoni (Miers) from the west coast of Sri Lanka was investigated based on catch/effort and length frequency data, using FiSAT software. Annual yield of M. dobsoni was estimated at 296 t in 1998 and 362 t in 1999. This species formed 54% of the total shrimp catch from the system. The asymptotic length (L) and the growth rate constant (K) were estimated to be 11.49 cm and 1.02 yr?1 for males and 12.8 cm and 1.73 yr?1 for females. The fishing mortality coefficients were 2.42 and 1.85 yr?1 for males and females, respectively. The natural mortality was estimated at 1.72 yr?1 for males and 2.51 yr?1 for females. The recruitment for the estuarine environment and the offshore areas was continuous but peaked twice per year. The maximum sustainable yield (MSY) was estimated at 294.65 t, around the current catch estimates. To obtain maximum sustainable economic yield (MSE = 293.56 t) the present effort should be reduced by 10%.  相似文献   
50.
Doppler velocity observations obtained by the Global Oscillation Network Group (GONG) instruments directly measure the nearly steady flows in the solar photosphere. The sun's differential rotation is accurately determined from single observations. The rotation profile with respect to latitude agrees well with previous measures, but it also shows a slight north-south asymmetry. Rotation profiles averaged over 27-day rotations of the sun reveal the torsional oscillation signal-weak, jetlike features, with amplitudes of 5 meters per second, that are associated with the sunspot latitude activity belts. A meridional circulation with a poleward flow of about 20 meters per second is also evident. Several characteristics of the surface flows suggest the presence of large convection cells.  相似文献   
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