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11.
Michele Barletta Marc Raffe 《The Canadian veterinary journal. La revue veterinaire canadienne》2016,57(3):258-264
Although sedatives are routinely administered to dogs for diagnostic and minimally invasive procedures, manual restraint is often used. The study compared intra-procedural behavioral response, scored on a 100-point, visual analog scale, and cost of restraint in healthy dogs given 1 of 5 treatments: manual restraint, dexmedetomidine at 125 μg/m2 (Dex 125) or 375 μg/m2 (Dex 375), Dex 125 plus butorphanol at 0.4 mg/kg (Dex 125 + Bu), or Dex 375 plus butorphanol at 0.4 mg/kg (Dex 375 + Bu). Mean behavioral response scores in dogs declined from baseline in the manual restraint group and improved in a linear fashion in the group order Dex 125, Dex 375, Dex 125 + Bu, and Dex 375 + Bu. Dexmedetomidine at 375 μg/m2 or at 125 μg/m2 or at 375 μg/m2 in combination with butorphanol produced the best intra-procedural behavioral response. The cost of sedative drugs was offset by the opportunity cost of diverting personnel from revenue-generating activity to manual restraint. 相似文献
12.
Fusellier M Desfontis JC Madec S Gautier F Debailleul M Gogny M 《American journal of veterinary research》2007,68(8):807-811
OBJECTIVE: To investigate renal function in clinically normal dogs when awake and during anesthesia with medetomidine; xylazine, ketamine, and halothane (XKH) combination; or propofol. ANIMALS: 10 adult female Beagles. PROCEDURES: At intervals of 15 days, dogs were administered medetomidine (0.05 mg/kg, IV); XKH combination (xylazine [1 mg/kg, IV], ketamine [5 mg/kg, IV], and halothane [1% end-tidal concentration]); or propofol (6 mg/kg, IV) to induce anesthesia or no treatment. Glomerular filtration rate was assessed on the basis of renal uptake (RU; determined via renal scintigraphy) and plasma clearance (CL) of technetium 99m-labeled diethylenetriamine pentaacetic acid ((99m)Tc-DTPA). RESULTS: In awake dogs, mean +/- SEM RU was 9.7 +/- 0.4% and CL was 3.86 +/- 0.23 mL/min/ kg. Renal uptake and CL of (99m)Tc-DTPA were not significantly modified by administration of XKH (RU, 11.4 +/- 0.9%; CL, 4.6 +/- 0.32 mL/min/kg) or propofol (RU, 9.7 +/- 0.3%; CL, 3.78 +/- 0.37 mL/min/kg). Half-life elimination time of plasma (99m)Tc-DTPA decreased significantly in XKH-anesthetized dogs, compared with the value in awake dogs (14.4 minutes and 28.9 minutes, respectively). However, glomerular filtration rate was significantly decreased by administration of medetomidine (RU, 3.9 +/- 0.1%), and the time to maximum kidney activity was significantly increased (867 +/- 56 seconds vs 181 +/- 11 seconds without anesthesia). CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that anesthesia with propofol or an XKH combination did not alter renal function in healthy Beagles, but anesthesia with medetomidine decreased early RU of (99m)Tc-DTPA. 相似文献
13.
Lenz M Drillich M Heuwieser W 《Berliner und Münchener tier?rztliche Wochenschrift》2007,120(5-6):237-244
The aim of this study was to determine signs of subclinical endometritis found by ultrasound that are associated with reduced fertility in dairy cows.The maximum diameter of the uterine lumen was determined by ultrasound in 324 cows without clinical signs of endometritis after evaluation of the genital tract 21 to 27 days postpartum. Cows were classified into healthy or with subclinical endometritis by three threshold values for the maximum uterine lumen diameter of 0.2 cm, 0.5 cm or 0.8 cm. Examinations by rectal palpation and ultrasound as well as classifications were repeated 14 days later. In addition, ovaries were scanned by ultrasound to determine the stage of the estrous cycle. In a subgroup of 103 cows the echotexture of the uterus and its contents was evaluated. In these cows the diagnosis of subclinical endometritis was performed by a scoring system. The diameter of the uterine lumen was significantly affected by stage of the estrous cycle at the time of examination. However, no effects were found for the stage of the cycle at the time of examination on subsequent reproductive performance. A uterine lumen with a maximum diameter of more than 0.2 cm showed a significant negative association with conception rate and proportion of cows pregnant. Classification based on higher threshold values did not reveal an association with reproductive performance. Echogenic content in the uterus also decreased reproductive performance. A classification based on the echotexture of the uterus and its contents revealed significant differences between healthy cows and cows with subclinical endometritis regarding the proportion of cows inseminated and pregnant.The results of this study showed that the diagnostic of bovine endometritis should be broadend by ultrasonography. The definition of subclinical endometritis diagnosed by means of ultrasonography has to be evaluated in further studies. 相似文献
14.
Little AA Steffey M Kraus MS 《Journal of the American Animal Hospital Association》2007,43(3):157-162
A 16-month-old, female German shepherd dog was presented with severe bicavitary effusions. A diaphragmatic hernia was diagnosed by thoracic radiography. An echocardiogram performed prior to surgical repair of the hernia revealed signs of cardiac tamponade, with right atrial collapse, in the absence of pericardial effusion. Right atrial collapse was presumed to be secondary to severe pleural effusion. At surgery, no pericardial disease was identified. Surgical correction of the diaphragmatic hernia resulted in resolution of the pleural and peritoneal effusions. Follow-up echocardiography demonstrated resolution of the signs of cardiac tamponade. 相似文献
15.
Logging pattern and landscape changes over the last century at the boreal and deciduous forest transition in Eastern Canada 总被引:4,自引:0,他引:4
Forestry practices associated with the industrial era (since ~1900) have altered the natural disturbance regimes and greatly
impacted the world’s forests. We quantified twentieth century logging patterns and regional scale consequences in three sub-boreal
forest landscapes of Eastern Canada (117,000, 49,400 and 92,300 ha), comparing forestry maps depicting age and forest cover
types for early industrial (1930) and present-day (2000) conditions. Results were similar for the three landscapes, indicating
large-scale forest change during the twentieth century. In 1930, previous logging activities had been concentrated in the
lowlands and along the main hydrographical network, as compared to a more even distribution over the landscapes in 2000, reflecting
a decreasing influence of the environmental constraints on forest harvesting. In 1930, old-aged forests (>100 years) accounted
for more than 75% of the unlogged areas of the three landscapes, as compared to less than 15% for the present-day conditions.
Logging practices have thus inverted the stand age distribution of the landscapes that are currently dominated by young and
regenerating stands. The 1930 forest cover types showed a clear relationship with elevation, with conifers located in the
lowlands and mixed and deciduous stands restricted to the upper slopes. Between 1930 and 2000, 58–64% of the conifer areas
transformed to mixed and deciduous forests, such that no clear altitudinal relationships remained in 2000. We conclude that
twentieth century logging practices have strongly altered the preindustrial vegetation patterns in our study area, to the
point that ecosystem-based management strategies should be developed to restore conifer dominance, altitudinal gradients,
as well as the irregular structure inspired from old forest stands. 相似文献
16.
Celia Carrillo Raquel Rey Marc Hendrickx María del Mar Cavia Sara Alonso-Torre 《Plant foods for human nutrition (Dordrecht, Netherlands)》2017,72(3):266-273
Red beetroot has been ranked among the 10 most potent antioxidant vegetables, although only extraction-based methods have been used to evaluate its total antioxidant capacity. Therefore, the present study aims at comparing the traditional extraction-based method with two more recent approaches (QUENCHER -QUick, Easy, New, CHEap and Reproducible- and GAR -global antioxidant response method), in order to establish their suitability in the case of beetroot. Our results indicate that the total antioxidant capacity of beetroot would be underestimated when using extraction-based procedures, since both QUENCHER and GAR methods resulted in a higher total antioxidant capacity. The effect of a thermal treatment on the total antioxidant capacity of beetroot varies among the methods evaluated and our findings suggest different compounds responsible for the total antioxidant capacity detected in each pre-processing method. Remarkably, the present study demonstrates that the traditional extraction-based method seems useful to screen for (changes in) the “bioavailable” antioxidant potential of the root. 相似文献
17.
Snyder Marcía N. Schumaker Nathan H. Ebersole Joseph L. Dunham Jason B. Comeleo Randy L. Keefer Matthew L. Leinenbach Peter Brookes Allen Cope Ben Wu Jennifer Palmer John Keenan Druscilla 《Landscape Ecology》2019,34(5):1197-1197
Landscape Ecology - In the original publication of the article, the third author name has been misspelt. The correct name is given in this Correction. The original version of this article was revised. 相似文献
18.
Van der Plancken I Van Loey A Hendrickx M 《Journal of agricultural and food chemistry》2007,55(1):127-135
This article addresses the effect of moisture content (0.8-9.9%) during dry-heating (80 degrees C) on selected physicochemical (solubility, turbidity, residual denaturation enthalpy, aggregation, surface hydrophobicity, and sulfhydryl content) and functional (foaming ability, foam density, and stability) properties of freeze-dried egg white (FDEW). Moisture content during dry-heating proved to be a parameter determining the functionality of the resulting egg white powder. The degree of conformational changes induced in the egg white proteins by dry-heating was strongly dependent on the amount of water present. Preferentially, dry-heating at 80 degrees C should be performed on egg white powder with a moisture content below 6.8%, as the loss of protein solubility above this value is extensive. In addition to insoluble aggregates, soluble, strongly stabilized aggregates were also formed, especially at higher moisture contents. The decrease in denaturation enthalpy, increase in surface hydrophobicity, and exposure of SH groups previously hidden in the protein core and their subsequent oxidation were more pronounced at prolonged dry-heating times and at higher moisture contents. These conformational changes resulted in improved foaming ability and foams with lower density. No effect of dry-heating on the foam stability was observed. 相似文献
19.
Bayuh Belay Abera Sabine Stuerz Kalimuthu Senthilkumar Marc Cotter Arisoa Rajaona Folkard Asch 《Journal of Agronomy and Crop Science》2020,206(4):433-443
Due to land expansion and an increase in productivity, rice production in sub-Saharan Africa has been growing at a rate of 6% in the past decade. Rainfed rice production systems have accounted for a large share of this expansion. In these systems, the potential growing period not only depends on the length of the rainy season and thus water availability, but is often, especially in the highlands of East Africa, bordered by the onset of the cool period of the year, when low minimum temperatures compromise rice yields. The objective of this study was to investigate the yield potential of 30 rice varieties contrasting in crop duration and cold tolerance in the highlands of East Africa, with its limited length of growing period. A field trial was conducted in the cropping seasons in 2016 and 2017 at the Fogera rice research station, Ethiopia. As a function of the onset of rains, rice was sown mid-July in 2016 and early July in 2017. Early sowing in 2017 led to an extended crop duration and significantly lower yields of the short-duration varieties, and to a shortened duration and significantly higher yields of the medium- and long-duration varieties, when compared to late sowing in 2016. Late sowing compromised yield of the medium- and long-duration varieties because of low temperatures during booting stage, which led to high spikelet sterility. Early sowing resulted in low yields of the short-duration varieties, probably due to low solar radiation during the cloudy rainy season, which coincided with the vegetative stage. Therefore, choice of variety should be a function of the variable onset of the rainy season and related sowing date. However, crop models precisely calibrated for potential varieties and the respective environmental conditions could fully support the selection of a suitable variety, depending on the date of sowing, for example with the help of online tools or smartphone applications. 相似文献
20.
Trevor J. Gilliland Paolo Annicchiarico Bernadette Julier Marc Ghesquière 《Grass and Forage Science》2020,75(3):227-241
Herbage production is regarded as having environment-friendly credentials. However, as the ruminant production it supports is facing major challenges on sustainability, environmental footprint and human health concerns, EU herbage cultivar testing must contribute to the solutions. Before new cultivars can be sold in a member state (MS) and gain EU-wide marketing, they must pass official tests to prove they are both novel (distinct, uniform and stable, DUS) with improved value for cultivation and use (VCU). Herbage species present specific challenges, as their allogamy imposes a wide within-cultivar variation that adds complexity to DUS tests and their “value” is only realized in ruminant produce. Current VCU systems measure production, chemical composition and disease/stress tolerances, often on large numbers of candidate cultivars, but prohibitive labour costs and logistics mean that animal intake, ruminant output or environmental benefits cannot be measured directly. Furthermore, some candidate cultivars with proven superior VCU fail DUS even though the non-distinct comparison is with a significantly lower performing registered cultivar. To resolve these problem cases, a “vmDUS” distinctness tool is proposed, which uses molecular markers but conforms to UPOV-declared principles. A short overview of current grassland research shows smart proxy measures of animal value can easily and quickly be adopted into an integrated pan-European (EU-VCU) test network. The proposed EU-VCU scheme will reallocate test resources to conduct these additional tests by placing MS in data sharing collaborations, while retaining their national listing authority. The benefits to all stakeholders from adopting these new testing procedures are considered. 相似文献