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151.
152.
Ali Al Haidar Frédéric Farnir Stefan Deleuze Charlotte Sandersen H. Amory 《Journal of Equine Veterinary Science》2010
The objective of this study was to compare the repeatability of echocardiographic measurements obtained from different echocardiographic modes and views in healthy adult equids of various sizes, breeds, and thorax shapes. Ten equids (body weight: 120–662 kg; age: 1–26 years) from various breeds, free of cardiac disease, were used in this study. Each animal was submitted to a standardized echocardiographic and Doppler protocol 3 times at 1 day interval. This protocol included the measurements of left and right ventricular, aortic, pulmonary, and left atrial parameters obtained from different views using the bidimensional (2D) or the motion (M) modes, and the measurement of several parameters of blood flow obtained from the pulsed wave Doppler mode. Repeatability of each measurement was estimated on the basis of the residual variance using a linear model and the coefficient of variation of repeated measurements. A two by two comparison of the repeatability of measurements performed in different views was performed using the residual variances in a variance ratio F test. Results showed that repeatability of echocardiographic or Doppler measurements in equids of various sizes, breeds, and thorax shapes are comparable to previously reported results in thoroughbred and standardbred horses. Left ventricular morphologic parameters showed a good repeatability in the classic M-mode right parasternal short axis view at the level of the chordae tendineae, but the 2D-mode right parasternal long axis four-chamber view appeared to offer an interesting alternative measurement. This latter view also allowed obtaining the most repeatable measurement of right ventricular internal diameter. The left atrial diameter was maximal and most repeatable in the 2D-mode left parasternal long axis four-chamber angled view, and the repeatability of the aortic diameter was best in the 2D-mode right parasternal long axis five-chamber view. Finally, aortic systolic time intervals were more repeatable when measured from the Doppler mode as compared with the M-mode. In conclusion, repeatability of echocardiographic measurements in horses could be optimized after the following protocol: (1) M-mode right parasternal short axis view at the level of chordae tendineae to measure left ventricular morphologic parameters, and 2D-mode right parasternal long axis four-chamber as an alternative view; (2) 2D-mode right parasternal long axis five-chambers to measure the aortic diameter; (3) 2D-mode left parasternal long axis four-chambers angled view to measure the left atrial diameter. 相似文献
153.
Denoeud F Henriet S Mungpakdee S Aury JM Da Silva C Brinkmann H Mikhaleva J Olsen LC Jubin C Cañestro C Bouquet JM Danks G Poulain J Campsteijn C Adamski M Cross I Yadetie F Muffato M Louis A Butcher S Tsagkogeorga G Konrad A Singh S Jensen MF Cong EH Eikeseth-Otteraa H Noel B Anthouard V Porcel BM Kachouri-Lafond R Nishino A Ugolini M Chourrout P Nishida H Aasland R Huzurbazar S Westhof E Delsuc F Lehrach H Reinhardt R Weissenbach J Roy SW Artiguenave F Postlethwait JH Manak JR Thompson EM 《Science (New York, N.Y.)》2010,330(6009):1381-1385
Genomes of animals as different as sponges and humans show conservation of global architecture. Here we show that multiple genomic features including transposon diversity, developmental gene repertoire, physical gene order, and intron-exon organization are shattered in the tunicate Oikopleura, belonging to the sister group of vertebrates and retaining chordate morphology. Ancestral architecture of animal genomes can be deeply modified and may therefore be largely nonadaptive. This rapidly evolving animal lineage thus offers unique perspectives on the level of genome plasticity. It also illuminates issues as fundamental as the mechanisms of intron gain. 相似文献
154.
Hamed Safafar Jonathan van Wagenen Per M?ller Charlotte Jacobsen 《Marine drugs》2015,13(12):7339-7356
This study aimed at investigating the potential of microalgae species grown on industrial waste water as a new source of natural antioxidants. Six microalgae from different classes, including Phaeodactylum sp. (Bacillariophyceae), Nannochloropsis sp. (Eustigmatophyceae), Chlorella sp., Dunaniella sp., and Desmodesmus sp. (Chlorophyta), were screened for their antioxidant properties using different in vitro assays. Natural antioxidants, including pigments, phenolics, and tocopherols, were measured in methanolic extracts of microalgae biomass. Highest and lowest concentrations of pigments, phenolic compounds, and tocopherols were found in Desmodesmus sp. and Phaeodactylum tricornuotom microalgae species, respectively. The results of each assay were correlated to the content of natural antioxidants in microalgae biomass. Phenolic compounds were found as major contributors to the antioxidant activity in all antioxidant tests while carotenoids were found to contribute to the 1,1-diphenyl-2-picryl-hydrazil (DPPH) radical scavenging activity, ferrous reduction power (FRAP), and ABTS-radical scavenging capacity activity. Desmodesmus sp. biomass represented a potentially rich source of natural antioxidants, such as carotenoids (lutein), tocopherols, and phenolic compounds when cultivated on industrial waste water as the main nutrient source. 相似文献
155.
Charlotte Falaise Cyrille Fran?ois Marie-Agnès Travers Benjamin Morga Jo?l Haure Réjean Tremblay Fran?ois Turcotte Pamela Pasetto Romain Gastineau Yann Hardivillier Vincent Leignel Jean-Luc Mouget 《Marine drugs》2016,14(9)
The search for novel compounds of marine origin has increased in the last decades for their application in various areas such as pharmaceutical, human or animal nutrition, cosmetics or bioenergy. In this context of blue technology development, microalgae are of particular interest due to their immense biodiversity and their relatively simple growth needs. In this review, we discuss about the promising use of microalgae and microalgal compounds as sources of natural antibiotics against human pathogens but also about their potential to limit microbial infections in aquaculture. An alternative to conventional antibiotics is needed as the microbial resistance to these drugs is increasing in humans and animals. Furthermore, using natural antibiotics for livestock could meet the consumer demand to avoid chemicals in food, would support a sustainable aquaculture and present the advantage of being environmentally friendly. Using natural and renewable microalgal compounds is still in its early days, but considering the important research development and rapid improvement in culture, extraction and purification processes, the valorization of microalgae will surely extend in the future. 相似文献
156.
157.
Synchronization of parturition in a commercial flock of sheep has many advantages including the maintenance of the efficiency of the operation as well as optimization of care for periparturient animals. In a research setting, using an ovine model for experiments involving the induction of parturition yields the results that can be applied to other mammalian species. In sheep, as well as in a variety of other farmed species, dexamethasone is the drug used to induce synchronized parturition at the end of gestation. However, considerable variations have been noticed in the time between induction and the onset of lambing. This study set out to determine the role that the breed of dam and sire, the age and reproductive history of ewes, the month of induction and the litter/lamb characteristics played in determining the time between dexamethasone treatment and parturition. The lambing was induced in 146 ewes (4 purebred Dorset, 19 purebred Rideau Arcott and 123 Rideau Arcott × Dorset ewes) using a single i.m. dose of 20 mg dexamethasone (Unidex®, Univet Pharmaceuticals, Milton, ON, Canada) on day 140 of gestation. The ewe breed was weakly correlated (r = − 0.19, P < 0.05) whereas the sire breed was moderately correlated (r = − 0.37, P < 0.001) to the time between dexamethasone treatment and the onset of parturition (the breed in this study was defined as the % of the Rideau Arcott genotype). The time between induction and the onset of labour averaged 57.3 ± 5.3 h and 64.3 ± 8.2 h in February and April, respectively, and it was significantly longer (P < 0.05) compared with the times recorded in July, September and November (42.0 ± 2.0 h, 38.7 ± 2.8 h and 36.1 ± 5.0 h, respectively). There was a negative correlation (r = − 0.41, P < 0.001) between the proportion of ram lambs and the mean birth weight of ewe lambs. These results can be interpreted to suggest that the breed and time of the year may both affect the synchrony of dexamethasone-induced lambing. The reasons for the associations found between the month of induction and the time elapsed to the onset of parturition as well as between the proportion of ram lambs and birth weights of ewe lambs are not fully understood and warrant further studies. 相似文献
158.
Gaby Van Galen DVM MSc DECEIM Helene Amory DVM PhD DECEIM Evita Busschers DVM DACVS Dominique Cassart DVM PhD Marco De Bruijn DVM DECEIM Vincent Gerber DVM PhD DECEIM John Keen DVM MSc DECEIM Laurence Lefere DVM Christel Marcillaud Pitel DVM Celia Marr DVM PhD DECEIM Jessica‐M. V. Müller DVM DECEIM Xavier Pineau DVM Claude Saegerman PhD Charlotte Sandersen DVM PhD DECEIM Didier Serteyn DVM PhD DECVAA Sara Torfs DVM Lucia Unger DVM Denis Verwilghen DVM MSc DECVS Dominique‐Marie Votion DVM PhD 《Journal of Veterinary Emergency and Critical Care》2010,20(5):528-532
Background – Atypical myopathy is an acute, severe rhabdomyolysis occurring in grazing horses. In the beginning of October 2009, a new outbreak occurred in several European countries. Geographic, demographic and clinical data of the reported cases in the month October 2009 are described. Key Findings – The survival rate in this outbreak was 25%. The most frequently observed clinical signs were congested mucous membranes, dyspnea, tachycardia, depression, weakness, stiffness, recumbency, trembling, sweating, and myoglobinuria. Nonsurvivors were significantly more likely to be recumbent than survivors. Prognostic factors, symptomatic treatment, and preventive measures are discussed. Significance – Differences were encountered during the described outbreak of atypical myopathy in October 2009 compared with previous outbreaks reported. Equine practitioners should be aware that previous epidemiological studies have shown that after a high prevalence in the autumn, new cases are likely to occur in the following spring. 相似文献
159.
Dominique Endamana Gill Shepherd George Akwah Neba Kenneth Angu Angu Chia Ntumwel Bonito Charlotte Eyong Ako 《Journal of Sustainable Forestry》2019,38(4):343-368
Reliable data on the contribution of forests to the livelihoods of households in the Congo Basin are not always readily available to governments and decision-makers. This paper assesses the value of forest resources on livelihoods in Cameroon, Republic of Congo, Gabon, Central Africa Republic and the Democratic Republic of Congo. Data were collected using the Forest Poverty Linkages Toolkit, between 2012 and 2014 on stratified samples of 616 Bantu and indigenous people’s households in 15 villages. The study reveals that forest resources account for 48% to 63% of the total revenue of rural households. In Bantu households, estimates of the gross income from the forest per capita/day range from $US 0.18 to $US 1.3. This value is about double that received by indigenous people except in Congo. Non-cash income is about twice as high as cash income. On average, cash income reaches only about 23% of the World Bank $1.25 a day income level for chronic poverty. However, non-cash income - about twice as high as cash income – mitigates these profound poverty levels to some extent. The paper concludes by considering the importance of the findings for policy-making in Central Africa and the Congo Basin, and more widely. It is suggested that much more data of this kind is need to shape appropriate approaches to sustainable forest management, with a better understanding of the economic security and the livelihood resilience of the chronic poor increasingly kept in mind. 相似文献
160.
Charlotte Mundy Nancy G. Creamer Carl R. Crozier L. George Wilson 《American Journal of Potato Research》1999,76(6):323-330
Planting three rows of potatoes in a bed the width of two conventional rows offers an easily managed way to increase seed piece populations, with the potential of increasing tuber yield and enhancing tuber quality. A wide bed production system (3 rows of potatoes planted on a 1.9 m flat-topped raised bed) was compared to a conventional-ridged system (1 row of potatoes in sharply sloped ridges on 96 cm centers) in 1996 and 1997 on a Norfolk sandy loam soil and a Portsmouth fine sandy loam soil in eastern North Carolina. Potato plant stands, leaf area index at approximately 9 WAP, yield, and quality were measured. Soil temperature, soil moisture, and cone index, as a measure of soil penetration resistance, were also measured, wide beds were more moist than conventional ridges early in the season. Cone index was greater throughout the root profile in wide beds in two of three tests. The row on the west side of an individual wide bed was most similar to conventional ridges in daily soil temperature fluctuations between minimum and maximum temperatures, and had greater fluctuations than the middle and eastern rows of the wide bed. Total yield and yield of grade A potatoes were not significantly different between wide beds and conventional ridges at either site. At one site, yield of grade B potatoes was significantly less in the wide bed; among the three rows in the wide bed, the eastern row had significantly lower yield of grade B potatoes. Conventional ridges had a higher percent of green grade A potatoes than the wide beds in one of three trials. Under North Carolina conditions, changing production systems would be unadvisable for most growers because wide beds do not increase yield enough to justify spending the money for more seed and to change equipment. 相似文献