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11.
The use of T-61 as a sole euthanasia agent for birds was investigated. Nine broiler chickens (Gallus gallus domesticus) were euthanized by intravenous T-61 and assessed for insensibility [brainstem reflexes: nictitating membrane reflex (NIC), palpebral blink reflex (PAL)], brain death [isoelectric electroencephalogram activity (EEG)], cessation of audible heartbeat, and abnormal electrocardiogram. Birds were considered dead when the heart rate was less than 180 beats/minute with an isoelectric EEG. No vocalization or wing flapping occurred. Both NIC and PAL were lost 10.5 s from start of injection and audible heartbeat ceased at 24.5 s. Latency to isoelectric activity was 16.6 s. All but 1 bird died within 60 s. Rapid induction of insensibility meant birds did not experience pain and distress within 10.5 s from start of injection and birds were not conscious during cardiac and circulatory arrest. Intravenous injection of T-61 is an effective and efficient euthanasia method for birds.  相似文献   
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The Nama-Karoo is the largest of the three biomes that comprise the semi-arid Karoo-Namib ecoregion of southern Africa. Large tracts of Nama-Karoo rangeland have been invaded by alien leguminous trees of the genus Prosopis. We assessed the impact of Prosopis invasion and clearing on vegetation cover in heavily grazed Nama-Karoo rangeland on two sheep farms in the Beaufort West district of the Western Cape province of South Africa. Our results suggest that, below critical threshold cover levels, Prosopis trees do not affect indigenous vegetation and add to overall rangeland vegetation cover. However, once Prosopis cover exceeds critical thresholds, the trees begin to negatively impact on indigenous vegetation (especially grasses) and overall vegetation cover. In addition, our data suggest that vegetation cover recovers after Prosopis clearing, being temporarily higher than pre-invasion levels possibly as a result of enhanced post-invasion soil fertility. Lastly, our results suggest that Prosopis trees reduce rangeland erosion potential at low cover and increase it after they exceed critical threshold cover. Information about thresholds of Prosopis impact can be used to direct clearing efforts for maximum benefit when resources are limited.  相似文献   
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Portable blood glucose meters (PBGM, glucometers) are a convenient, cost effective, and quick means to assess patient blood glucose concentration. The number of commercially available PBGM is constantly increasing, making it challenging to determine whether certain glucometers may have benefits over others for veterinary testing. The challenge in selection of an appropriate glucometer from a quality perspective is compounded by the variety of analytic methods used to quantify glucose concentrations and disparate statistical analysis in many published studies. These guidelines were developed as part of the ASVCP QALS committee response to establish recommendations to improve the quality of testing using point‐of‐care testing (POCT) handheld and benchtop devices in veterinary medicine. They are intended for clinical pathologists and laboratory professionals to provide them with background knowledge and specific recommendations for quality assurance (QA) and quality control (QC), and to serve as a resource to assist the provision of advice to veterinarians and technicians to improve the quality of results obtained when using PBGM. These guidelines are not intended to be all‐inclusive; rather they provide a minimum standard for management of PBGM in the veterinary setting.  相似文献   
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OBJECTIVE: To evaluate the use of computed tomography (CT) for detection of pneumonia in snakes. ANIMALS: 8 clinically normal Indian pythons (Python molurus) and 5 pythons with evidence of respiratory tract disease. PROCEDURES: Preliminary examinations (clinical examination, conventional radiography, and microbiologic examination of a transtracheal wash sample) were performed. The lungs of each snake were then examined by use of CT performed in accordance with a standardized protocol. Structures of the lungs were assessed, and thickness and attenuation of the parenchyma were determined. RESULTS: It was possible to assess lung parenchyma in all pythons. Mean +/- SD attenuation in healthy pythons was -744.4 +/- 47.1 Hounsfield units. Significant differences were not evident between the right and left lungs or among measurement areas within a lung. In all Indian pythons with clinical signs of dyspnea and microbiologic detection of pathogens, hyperattenuation of the alveolar tissue was evident. CONCLUSIONS AND CLINICAL RELEVANCE: Analysis of the results revealed the benefit of CT for use in the diagnosis of pneumonia in snakes. A standardized protocol and reference values were established as a basis for CT assessment of the lungs of snakes.  相似文献   
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At the Institute of Animal Nutrition of the Federal Agricultural Research Centre (FAL) in Braunschweig a feeding trial with 30 first lactating cows (German Holstein) was realised in 2004 for a complete lactation. All animals received a diet based on maize- and grass-silage ad libitum at the rate of 60:40 (DM-base) and concentrate depending on their milk yield.The animals were fed with energy and protein as recommended (GfE 2001) and were kept in loose housing. After calving they were split randomly into two feeding groups with 15 animals each. Group 1 was fed a concentrate according to the recommendations of the GfE (2001), whereas group 2 was offered the same concentrate with roughly the double amount of calcium, magnesium, phosphorus, copper, zinc, beta-carotene and vitamins A and E. To study the influence of the different concentrates on the serum concentrations of minerals and vitamins, blood, feed and milk samples were regularly taken and analysed in the course of lactation. Significantly higher blood concentrations were detected for phosphorus, zinc and vitamin E in group 2, but therefore a direct influence of the feeding on the blood concentrations was detected only for zinc and vitamin E. Over the whole lactation the average milk yield of group 1 was 2.6 kg/day higher and the average milk fat content was reduced about 0.6 percent points compared to group 2.  相似文献   
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The purpose of this study was to determine the prevalence of positive allergen reactions in cats with small-airway disease (i.e. 'feline asthma', 'feline allergic bronchitis', 'feline bronchial disease'). Intradermal skin tests (IDT) and serum immunoglobulin E (IgE) tests were performed in 10 cats with idiopathic small-airway disease and in 10 normal cats without a history of respiratory disease. None of the cats had a history of skin disease or clinical signs of skin disease at the time of testing. Significantly more individual positive allergen reactions were found on serum IgE tests than on IDT in both groups of cats. Affected cats had significantly more individual positive allergen reactions on both tests than unaffected cats. Both IDT and serum IgE tests resulted in more individual positive allergen reactions to weeds, trees, grasses, and/or moulds in affected cats than in normal cats. Significantly more positive allergen reactions to house dust mites were found in affected compared to non-affected cats by IDT but not by serum IgE testing. One unexpected obstacle to inclusion of more affected cats in the study was the concurrent presence or history of suspect or known allergic skin disease. Concurrent allergic skin disease has not been reported in association with small-airway disease in cats. The increased prevalence of individual positive allergen reactions in affected cats may be due to increased immunological reactivity in these cats. Further studies are needed to answer this question and to determine what role, if any, aeroallergens have in the pathogenesis of this complex feline disease.  相似文献   
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