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1.
The objective of this study was to examine the efficacy of a caudal epidural anaesthesia using lidocaine or xylazine in a high volume for analgesia of the flank, navel and hamstring tendon. Fourteen calves weighing 57.7 +/- 5.1 kg and 37.9 +/- 9.3 (mean +/- SEM) days old were randomly divided into two groups of seven calves each. Calves belonging to the lidocaine group were given a 2% lidocaine solution in the sacrococcygeal vertebral space epidurally at a volume of 0.4 ml/kg (8 mg/kg) body weight (BW). Animals of the xylazine group were administered an epidural anaesthesia with xylazine at a dose of 0.1 mg/kg BW, diluted with a 0.9% saline solution to a corresponding final volume of 0.4 ml/kg BW. Heart rate and respiratory rate were measured and the degree and duration of analgesia was determined by the response to a skin prick with a hypodermic needle over a period of 350 min after epidural injection. After epidural anaesthesia with lidocaine the mean heart rate increased during dorsal recumbency, whereas after xylazine both heart rate and respiratory rate decreased significantly (P < 0.05). The epidural injection of xylazine compared with lidocaine caused longer (P < 0.05) analgesia at the hamstring tendon (mean +/- SEM, 120.7 +/- 29.7 min versus 93.6 +/- 3.5 min) and at the flank (100.7 +/- 24.4 min versus 78.3 +/- 11.1 min). There were no differences in the intensity of analgesia between groups. After xylazine application analgesia at the navel was achieved for 95.0 +/- 14.1 min whereas after lidocaine injection sufficient analgesia at the navel was found in just two of seven calves for 55 and 95 min respectively. Based on above experiences, a second study was performed, in which a combination of xylazine and local anaesthetics was used and the injection volume was increased to prove the efficacy of caudal epidural anaesthesia in 15 calves (26.3 +/- 26.7 days; 57.1 +/- 19.5 kg) submitted to the clinic for regular umbilical surgery. In these cases the xylazine (0.1 mg/kg BW) was diluted with 2% lidocaine (n = 7) or 2% procaine (n = 8) to a corresponding final volume of 0.5-0.6 ml/kg BW. In all cases complete anaesthesia of the surgical area was achieved and no adverse effects were observed. Overall the high volume caudal epidural anaesthesia represents an effective, safe, cheap and easy to perform alternative for anaesthesia of the navel, flank and hamstring tendon in calves without major side effects.  相似文献   
2.
目前在区域旅游开发中,对区域内旅游景点数量特征的研究多用定性描述的方法进行,为了使研究更加科学而有意义,急需进行定量化研究。该文以河北省满城县为例,采用景点调查、GPS定位和文件读取相结合的方法,按照相关标准将210个景点分成景系—景类—景型三个层次,在MapInfo软件的支持下,按景类在基础要素图上标注并绘制出满城县旅游景点类型分布图,然后借鉴景观指数的思维方法,定量描述了景点的数量特征。主要结论为满城县的旅游景点大多分布在该县的中部、西部和北部,AA地文景观、AB水文景观、AC气候生物、BA历史遗迹和CA旅游服务等5个景类分布较广,东部和南部旅游景点分布少且不广,多为BB现代人文吸引物景类,并指明了原因;通过定量表达各乡镇旅游景点的数量及类型,从而便于各乡镇了解自身景点的赋存状况,提出针对性的发展对策;分析了景点的多样性指数H、均匀性指数E、优势度指数D和丰富度指数R,并说明了原因,为旅游景点的研究提供了一种有益的方法和独特的视角。  相似文献   
3.
河北省农家旅馆近年发展迅猛,在带动当地经济发展的同时,也出现了良莠不齐的经营局面,为河北省旅游业的发展带来了诸多负面影响。农家旅馆的标准化经营已经成了河北省旅游发展中迫在眉睫的任务。本文在查询及借鉴兄弟省份已有农家旅馆评定标准的基础上,提出了河北省农家旅馆经营的准入条件,并初步构建了我省农家旅馆的评价标准,以期为我省农家旅馆的持续健康经营提供有效参考  相似文献   
4.
5.
During an outbreak of pneumonia and arthritis in beef calves and young cattle on a large farm in north-west Germany, Mycoplasma bovis and Mycoplasma californicum were isolated from tracheobronchial lavage fluids and synovial fluids. The microbiological findings in dead and living animals and the immunohistochemical demonstration of M californicum antigen in lung and arthritic joint tissue, indicated that under poor housing conditions and possibly other predisposing factors, this mycoplasma, like M bovis, can colonise the respiratory tract and may be able to cross the respiratory mucosal barrier to spread through an infected animal and cause systemic infections that may contribute to severe arthritis.  相似文献   
6.
Inflammatory adhesions between reticulum and ventral abdomen in patients suffering traumatic reticuloperitonitis (TRP) may induce a massive inhibition of reticular contractions and thereby an impairment of the separation process of particles in the reticulorumen. However, a substantial disturbance of digesta passage (Hoflund-syndrome) is found only in a few TRP-cows. We hypothesized that this is due to a retrieval of reticular motility due to rebuilding and degradation of adhesions within months after the removal of the foreign body as the primary inflammatory stimulus. Accordingly, it was the objective of this study (a) to assess the extent and structure of inflammatory adhesions in cows with TRP over a period of six months following surgery and (b) to persecute reticular function by characterizing the sequence of reticular contractions sonographically and by assessment of particle size distribution in the faeces of patients by means of wet-sieving. Twenty-six cows suffering from TRP were studied on the day of rumenotomy (day 1) and on day 6, day 12 and 6 months post operationem. Additionally, six healthy control cows were investigated once. All cows were on a hay and concentrate diet. On day 1, the reticular floor and the reticular wall were affected by adhesions in varying extent in all cows; the contraction distance and contraction velocity of the reticulum were markedly reduced and the portion of large particles in the faces increased compared to healthy cows. On day 12, the portion of large particles did not vary any more from that of control cows; a tendency towards an increased contraction distance compared to day 1 was found. Sonographically, only marginal differences were detected in respect to extent and consistency of adhesions. Six months after rumenotomy, in 9 of 16 re-investigated cows sonography revealed no adhesions at the reticulum at all, in other cases the extent of adhesions shrunk considerably. Contraction distance and contraction velocity and particle size distribution in the faeces were found to be nearly comparable to that of control cows. It is concluded that inflammatory adhesions disappear in the majority of the TRP-patients, as a consequence reticular function normalizes. A serious disturbance of digesta passage seems to develop exclusively in those patients with the most extensive adhesions and may be also in such cows, where the primary adhesions cause the development of extensive abscesses.  相似文献   
7.
旅游形象设计是我国现阶段旅游规划的发展方向和重要内容。本文以河北省狼牙山森林公园为对象,采用适用于各类型旅游地的形象设计技术体系进行全面分析。在此基础上,在CIS理论的基础上重新构建在旅游形象设计框架下对该公园的旅游形象进行了多方案设计,对该公园的合理开发保护有一定的指导意义。  相似文献   
8.
 由于卧龙山庄原规划已时过境迁,已经不能满足需要,因而急需进行重新规划和对规划后的方案进行系统评价。该文通过实地调查、GPS定位相结合的方法查清了现有旅游资源并在此基础上进行了规划,然后运用景观生态学方法对规划后的方案进行了评价。该文规划种植了酸枣、冬枣、梨枣、月光枣、野菜、柿子、欧李,改变了蔬菜园的种植种类;增加了杜梨、栾树和红叶臭椿的种植面积;规划了生态集雨工程示范点、火箭消雷展览室、卧龙禅寺、金鱼池、观鱼长廊、商店、观景亭、道路、停车场和厕所等。用斑块水平和景观水平上的景观指数作为规划方案评价的数量指标,对规划后的效果进行评定,认为规划后虽然景观破碎化指数提高了,但景观类型集中度加强;景观多样性指数、优势度指数、丰富度均提高了,美学质量得到改善,旅游设施更为完善,游览期更长;同时认为这种评价方法在规划方案筛选中具有一定的可行性和参考性。  相似文献   
9.
Habitat connectivity is a central factor in shaping aquatic biological communities, but few tools exist to describe and quantify this attribute at a network scale in riverine systems. Here, we develop a new index to quantify longitudinal connectivity of river networks based on the expected probability of an organism being able to move freely between two random points of the network. We apply this index to two fish life histories and evaluate the effects of the number, passability, and placement of barriers on river network connectivity through the use of simulated dendritic ecological networks. We then extend the index to a real world dendritic river system in Newfoundland, Canada. Our results indicate that connectivity in river systems, as represented by our index, is most impacted by the first few barriers added to the system. This is in contrast to terrestrial systems, which are more resilient to low levels of connectivity. The results show a curvilinear relationship between barrier passability and structural connectivity. This suggests that an incremental improvement in passability would result in a greater improvement to river network connectivity for more permeable barriers than for less permeable barriers. Our analysis of the index in simulated and real river networks also showed that barrier placement played an important role in connectivity. Not surprisingly, barriers located near the river mouth have the greatest impact on fish with diadromous life histories while those located near the center of the river network have the most impact on fish with potadromous life histories. The proposed index is conceptually simple and sufficiently flexible to deal with variations in river structure and biological communities. The index will enable researchers to account for connectivity in habitat studies and will also allow resource managers to characterize watersheds, assess cumulative impacts of multiple barriers and determine priorities for restoration.  相似文献   
10.
The objective was to examine whether the administration of colostrum by a drencher is a safe method to achieve satisfying immunoglobulin concentrations in newborn Holstein Friesian (HF)-calves. Twenty-one calves were fed 1 h postnatum with 2 l colostrum from their dam using a nipple bottle (group I); 15 calves were drenched with 4 l colostrum from their dam 1 h postnatum (group II). Thereafter, all calves were fed milk replacer exclusively. Serum concentration of total immunoglobulin [analysed by Sandwich-enzyme-linked immunosorbent assay (ELISA)] 24 h postnatum was higher in drenched calves (25.2 g/l; 12.8/52.2; median and 10/90 percentiles) compared with bottle-fed calves (14.1 g/l; 9.2/24.7). To characterize the kinetics of immunoglobulin absorption, 17 blood samples were taken frequently within 72 h postnatum using a jugular catheter in five calves fed 2 l colostrum by nipple bottle and five calves drenched with 4 l colostrum 1 h postnatum. A slightly delayed increase of serum immunoglobulin concentration (approximately 3 h) was obvious in drenched calves compared with bottle-fed calves, but drenched calves reached significantly higher immunoglobulin concentrations compared with bottle-fed calves. It is concluded that the proper application of colostrum by a drencher is a useful method for adequate colostral supply in newborn calves. The failure of the oesophageal groove reflex in drenched calves caused no clinical consequences.  相似文献   
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