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ObjectiveTo elaborate constant rate infusion (CRI) protocols for xylazine (X) and xylazine/butorphanol (XB) which will result in constant sedation and steady xylazine plasma concentrations.Study designBlinded randomized experimental study.AnimalsTen adult research horses.MethodsPart I: After normal height of head above ground (HHAG = 100%) was determined, a loading dose of xylazine (1 mg kg?1) with butorphanol (XB: 18 μg kg?1) or saline (X: equal volume) was given slowly intravenously (IV). Immediately afterwards, a CRI of butorphanol (XB: 25 μg kg?1 hour?1) or saline (X) was administered for 2 hours. The HHAG was used as a marker of depth of sedation. Sedation was maintained for 2 hours by additional boluses of xylazine (0.3 mg kg?1) whenever HHAG >50%. The dose of xylazine (mg kg?1 hour?1) required to maintain sedation was calculated for both groups. Part II: After the initial loading dose, the calculated xylazine infusion rates were administered in parallel to butorphanol (XB) or saline (X) and sedation evaluated. Xylazine plasma concentrations were measured by HPLC-MS-MS at time points 0, 5, 30, 45, 60, 90, and 120 minutes. Data were analyzed using paired t-test, Wilcoxon signed rank test and a 2-way anova for repeated measures (p < 0.05).ResultsThere was no significant difference in xylazine requirements (X: 0.69, XB: 0.65 mg kg?1 hour?1) between groups. With treatment X, a CRI leading to prolonged sedation was developed. With XB, five horses (part I: two, part II: three) fell down and during part II four horses appeared insufficiently sedated. Xylazine plasma concentrations were constant after 45 minutes in both groups.ConclusionXylazine bolus, followed by CRI, provided constant sedation. Additional butorphanol was ineffective in reducing xylazine requirements and increased ataxia and apparent early recovery from sedation in unstimulated horses.Clinical relevanceData were obtained on unstimulated healthy horses and extrapolation to clinical conditions requires caution.  相似文献   
85.
Over the last century, island biodiversity has become one of the most threatened in the world. Although many island conservation plans address biodiversity requirements at the species level, few plans address the spatial requirements of the biodiversity processes that underpin the persistence of these species. Using systematic conservation planning principles, we map the spatial components of biodiversity processes (SCBPs) and use these to design broad-scale conservation corridors for Réunion Island. Our method is based upon a literature review, expert knowledge, spatially explicit base data, conservation planning software, and spatial modelling. We combine a target-driven algorithm with least-cost path analyses to delineate optimal corridors for capturing key biodiversity processes while simultaneously considering biodiversity pattern targets, conservation opportunities, and future threats. We identify five SCBPs: the oceanic-terrestrial interface; riverine corridors; macrohabitat interfaces; the boundaries of isolated topographic units; and lowland-upland gradients. A large proportion of the SCBPs (81.3%) is currently untransformed, whereas 3% is irreversibly transformed by urbanisation and 15.7% is transformed but restorable. However, SCBPs are almost fully disrupted by urbanisation in the lowlands, thereby compromising functional corridors along full altitudinal gradients. This study is a contribution toward the reconciliation of conservation versus development objectives on Réunion Island but we believe that the delineation method is sufficiently general to be applied to other islands. Our results highlight the need for integrating marine, coastal and terrestrial conservation planning as a matter of urgency, given the rapid transformation of coastal areas on islands.  相似文献   
86.

Objectives

To compare the effects of a lidocaine constant rate infusion (CRI) combined with 1% isoflurane versus those of 2% isoflurane alone on cardiovascular variables in anaesthetized horses, and to estimate the sample size required to detect a difference in recovery quality.

Study design

Prospective, randomized, blinded, crossover study.

Animals

Twelve healthy experimental horses.

Methods

Horses were anaesthetized twice using an intravenous (IV) administration of acepromazine, romifidine, diazepam and ketamine. Horses were placed in dorsal recumbency and ventilated mechanically. During the first 10 minutes (P1), anaesthesia was maintained with a 2% inspired isoflurane fraction (FIIso). During the following 20 minutes (P2), horses received IV lidocaine (1.5 mg kg?1) (group IL) or saline (group I). During the last 60 minutes (P3), group IL received a lidocaine CRI (50 μg kg?1 minute?1 IV) and FIIso 1%, whereas group I received a saline CRI and FIIso 2%. Three weeks later, the horses received the alternative treatment. Painful stimuli were induced by introducing an 18 gauge needle intramuscularly. Ketamine and dobutamine requirements and physiological variables were recorded. Recoveries were assessed by two anaesthetists unaware of the treatment. Lidocaine plasma concentrations were measured during recovery. Data were analysed with anova.

Results

During P3, group IL had a lower heart rate (p = 0.002), higher mean arterial pressure (p < 0.001) and lower dobutamine requirement (p < 0.001) than group I. One horse had lidocaine plasma concentrations above toxic levels. Recoveries did not differ significantly between groups. Sample sizes of 208 horses in each group would be necessary to detect a statistically significant difference (85% statistical power) in recovery quality.

Conclusions and clinical relevance

A lidocaine CRI combined with FIIso 1% rather than FIIso 2% alone may improve cardiovascular variables in healthy anaesthetized horses.  相似文献   
87.
Journal of Plant Diseases and Protection - Recent review described that grape anthracnose in Brazil is caused by Elsinoe ampelina. However, in many countries, anthracnose can be associated with...  相似文献   
88.
The Black Sea is a semi-enclosed body of water that differs from the adjacent Mediterranean Sea in terms of its biodiversity, oceanographical and ecological characteristics. There is growing international concern about pollution in the Black Sea and other anthropogenic threats to its fauna. The bottlenose dolphin (Tursiops truncatus) is one of three species of cetaceans living in the Azov-Black Sea basin. Despite considerable research on bottlenose dolphins elsewhere, the extent of human impacts on the Black Sea populations is unknown. Previous attempts to award special conservation status to Black Sea cetaceans have failed specifically because policy makers have viewed their ecological and evolutionary uniqueness as equivocal. This study assessed divergence between Black Sea, Mediterranean Sea and Atlantic Ocean bottlenose dolphins for 26 cranial measurements (n = 75 adult bottlenose dolphin skulls) and mitochondrial DNA (n = 99 individuals). Black Sea bottlenose dolphins are smaller than those in the Mediterranean, and possess a uniquely shaped skull. As in a previous study, we found the Black Sea population to be genetically distinct, with relatively low levels of mtDNA diversity. Population genetic models suggest that Black Sea bottlenose dolphins have so little gene flow with the Mediterranean due to historical isolation that they should be managed separately.  相似文献   
89.
Neospora caninum, an apicomplexan protozoan parasite, is recognized as a major cause of abortion in cattle while limited information is presently available on association between equine Neospora infections and abortions. The aim of the present study was to document prevalence of antibodies against Neospora sp. in aborted mares as a clue to the role of N. caninum in mare reproductive failure in Normandy, France. Using an agglutination test, the number of animals with elevated (>80) anti-Neospora sp. antibody titer was higher in a group of 54 aborted mares than in randomly chosen groups of 45 mares and 76 horses sampled for equine arteritis virus and Fasciola hepatica antibodies, respectively (P<0.001). N. caninum DNA was found in 3/91 fetal brains, 2/77 fetal hearts, and 1/1 placenta, and present in both brains and hearts of two fetuses. In 13 cases for which both mare serum and fetus were available, no fetal N. caninum amplification product was present while a large variation of maternal antibody titers was found. Data prompt at additional surveys of association between equine reproductive failure and Neospora sp. infection.  相似文献   
90.
Since the mid eighties, agricultural development and increased population growth in Vietnam’s northern highlands have modified land use patterns and thus, increased the runoff process and soil degradation induced by water erosion. In the last decade, Vietnamese literature has focused on the computation of soil losses over large areas. Most of these spatial and quantitative soil erosion studies do not consider the impact of agricultural land use diversity (spatial heterogeneity), particularly at the watershed scale, and the annual variability of seasonal landscape factors on soil erosion vulnerability and hence, landscape dynamics. We present an integrated approach combining field measurements and observations, GIS and modeling to determine the spatial and temporal dynamics of soil erosion vulnerability according to watershed units and hence, the impact of physical environment components and agricultural land use patterns on landscape evolution. Tables and graphics showing the cropping systems, the periods within a year, and the watershed units that are most vulnerable are presented. The double cultivation cycles for paddy rice fields not only imply two periods of land preparation and establishment that expose the soil surface to raindrop impacts, but also increased soil management practices that decrease the soil’s resistance to detachment. Despite the low levels of soil management practices for the shifting cultivation system, the near absence of soil conservation practices clearly increases their vulnerability. Hence, rainfed cropping systems, mainly soya and cassava, cultivated on sloping lands (hills and mountains) where soil erosion vulnerability is the highest represent the watershed units which are the most prone to soil loss.  相似文献   
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