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61.
Prothrombin time and activated partial thromboplastin time using a point‐of‐care analyser (Abaxis VSpro®) in Bennett's wallabies (Macropus rufogriseus)
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BN Nevitt SK Chinnadurai MK Watson JN Langan MJ Adkesson 《Australian veterinary journal》2016,94(10):384-386
There are few reports of coagulation times in marsupial species. Blood samples collected from 14 Bennett's wallabies (Macropus rufogriseus) under anaesthesia during routine health assessments were analysed for prothrombin time (PT) and activated partial thromboplastin time (aPTT) using a point‐of‐care analyser (POC) (Abaxis VSPro®). The wallabies had an aPTT mean of 78.09 s and median of 78.1 s. The PT for all wallabies was greater than 35 s, exceeding the longest time measured on the POC. Although PT was significantly longer, aPTT was similar to the manufacturer's domestic canine reference range. 相似文献
62.
63.
Acorn production is one of the most important products in silvopastoral systems in the Mediterranean region. In the present
study we carried out two preliminary trials to analyze the distribution of production over time and the effect of pruning.
The objective was to develop tools to manage this valuable resource within these systems. In the first part of the study,
we analyzed the total acorn production of a holm oak stand, and its seasonal distribution (October–January) over two years
(1997–1998 and 1998–1999) in five sites in the southwest of Spain. Mean total acorn production ranged from 590 to 830 kg ha−1. There was considerable variation between the different sites and years studied, as was expected from studies on other oak
species. A comparison was also made of acorn production, comparing annual acorn production between 40 pruned and 40 non-pruned
trees, for the period 1994–1999. There was an interaction between ‘pruning treatment’ and ‘year’. Pruning, significantly decreased
acorn production in all but two years when production was above the average, whereas production was not affected by pruning
the three years that acorn yield was below the average. The study of acorn production and the analysis of the effect of pruning,
needs to be studied over a longer time period. 相似文献
64.
目前,玻利维亚森林认证总面积为 886 977 hm2,其中包括租借地、私有林和社区经营的森林。认证的社区森林的总面积为5.3万hm2,均属于Lonerio社区林业项目所有,其森林管理者是当地社区。认证者是社区代理组织APCOB(即对玻利维亚东部农民和土著人的支持)/CICOL(即玻利维亚东部公共中心)。 玻利维亚社区管理的森林面积为 258 821 hm2。为通过森林管理委员会(FSC)的认证,社区按FSC的要求制定了这片林地的森林经营计划,并按其计划进行了森林管理。FSC的主要要求之一是需要认证的经营单位必须按照FSC认证的原则和标准… 相似文献
65.
Montero-Astúa M Hartung JS Aguilar E Chacón C Li W Albertazzi FJ Rivera C 《Phytopathology》2007,97(10):1338-1347
ABSTRACT The diversity of 42 Xylella fastidiosa strains from Costa Rica, S?o Paulo, Brazil, and the United States were analyzed using the sequence of the 16S rRNA gene by variable number of tandem repeat (VNTR) fragment analysis and by restriction fragment length polymorphisms (RFLP) of a specific polymerase chain reaction (PCR)-amplification product using enzyme CfoI. Limited variability in the sequence of the 16S rRNA gene was observed and, although the separation was not absolute, most strains from Costa Rica clustered with strains from the United States and not with strains from S?o Paulo. The PCR-RFLP produced different patterns of DNA bands. The same pattern was shared by strains from Costa Rica, the United States, and two coffee strains from S?o Paulo, but a different pattern was observed in six coffee and orange strains from Brazil. In all, 32 amplification products were scored in the VNTR fragment analysis. The total variation observed among the X. fastidiosa strains had significant (P < 0.001) contributions from both geography and host origin as inferred by Nei's values of genetic diversity and WINAMOVA statistics. The strains from Costa Rica were isolated from diseased grapevines, coffee, and sweet orange and these strains grouped together and could be distinguished from strains from grapevine from the United States or from either coffee or sweet orange from S?o Paulo. The strains tested from Costa Rica are most likely of local origin, although the possibility that they have been introduced along with horticultural crops cannot be excluded. In either case, they are examples of independent selection of strains of X. fastidiosa affecting coffee and sweet orange. Greater genetic similarity was observed between strains from Costa Rica and the United States than with those from S?o Paulo. 相似文献
66.
Javier J. Aguilar Juan Cuervo-Arango Horacio Mouguelar Luis Losinno 《Journal of Equine Veterinary Science》2012
The objective of this work was to study cellular changes in the epithelium of the mare’s oviduct. Oviductal samples were taken from mares at different reproductive stages for optical microscopy and Hoechst 33258 staining. Glandular-like structures were observed in 100% of the oviducts. These structures were of the tubular type and were formed by ciliated and nonciliated epithelial cells arranged in a way similar to the epithelial surface. The amount of structures decreased progressively from the ampulla to the isthmus, but did not change through the different reproductive stages. Histological changes in the epithelium of the oviduct were observed associated with the reproductive stages. In the ampulla, the amount of ciliated cells decreased in the anovulatory phase compared with other reproductive stages. Cords of connective tissue lined by epithelium (trabeculae) and dividing completely the lumen of the oviduct were found in 50% of the oviducts. Epithelial cells projected toward the lumen as large vesicles of cytoplasm, sometimes containing a nucleus. The amount of cells presenting nuclear protrusion varied throughout the oviduct, with highest incidence in the ampulla, decreasing progressively toward the isthmus (P < .05). In addition, nuclear protrusions were higher in number during the anovulatory and luteal phases than in the other reproductive stages (P < .05). These nuclear protruding cells appeared to be extruding from the epithelium and showed no signs of apoptosis based on the histological and fluorescent stains used. The existence of these gland-like structures in the oviductal mucosa should be considered when studying the oviductal physiology in mares. 相似文献
67.
Hernández DM Díaz-Ruiz G Rivero-Cruz BE Bye RA Aguilar MI Rivero-Cruz JF 《Fitoterapia》2012,83(3):527-531
From the roots of Iostephane heterophylla, six known compounds, namely, ent-trachyloban-19-oic acid (1), the mixture of ent-kaur-16-en-19-oic acid (2) and ent-beyer-15-en-19-oic acid (3), xanthorrhizol (4), 16α-hydroxy-ent-kaurane (5) and 16α-hydroxy-ent-kaur-11-en-19-oic acid (6) were isolated using a bioassay-guided fractionation method. The known compounds (1-6) were identified by comparison of their spectroscopic data with reported values in the literature. In an attempt to increase the resultant antimicrobial activity of 1 and 4, a series of reactions was performed on ent-trachyloban-19-oic acid (1) and xanthorrhizol (4), to obtain derivatives 1a, 1b, and 4a-4d. All the isolated compounds (1-6) and the derivatives 1a, 1b, and 4a-4d were evaluated for their antimicrobial activity against two oral pathogens, Streptococcus mutans and Porphyromonas gingivalis associated with caries and periodontal disease, respectively. Compounds 1, 1b, 2+3, 4 and 4d inhibited the growth of S. mutans with concentrations ranging from 4.1 μg/mL to 70.5 μg/mL. No significant activity was found on P. gingivalis except for 4 with an MIC of 6.8 μg/mL. The ability of 1, 1b, 2+3, 4 and 4d to inhibit biofilm formation by S. mutans was evaluated. It was found that 1, 1b, 4 and 4d interfered with the establishment of S. mutans biofilms, inhibiting their development at 32.5, 125.0, 14.1 and 24.4 μg/mL, respectively. 相似文献
68.
MJ Lancaster JS Nimmo C Lenghaus IJ Gill RD Crawford RT Badman JL Samuel CJ Werner C Button N Kvalheim 《Australian veterinary journal》2009,87(12):476-479
Objective To document an ovine disease attributed to the consumption of Lythrum hyssopifolia (lesser loosestrife). Procedures Historical and histological review of field and experimental cases. Results 1–20% mortality occurred in sheep flocks grazing paddocks where L. hyssopifolia was the predominant green vegetation. Well‐documented disease outbreaks occurred in summer on nine farms across Victoria between 1974 and 2002. Liver damage occurred in all nine outbreaks, with kidney damage in at least eight. Hepatocyte necrosis was usually zonal to midzonal (zone 2) in the liver samples from four farms and periacinar (zone 3) in those from three farms, but some livers showed only single‐cell necrosis. Multinucleate hepatocytes near necrotic areas were a feature in six cases. Proximal tubular epithelium appeared to be the primary renal target and brown granules were often present in renal tubules. Biochemical and histological evidence of liver and kidney damage was obtained from two sheep experimentally pen‐fed harvested L. hyssopifolia. Conclusion Chemicals in L. hyssopifolia are toxic to ovine hepatocytes and renal tubular epithelial cells. 相似文献
69.
Intra-specific diversity within Moraxella bovis was investigated analysing DNA fingerprints, outer membrane proteins (OMP) and lipopolysaccharides (LPS) profiles. Three collection strains and 57 isolates of M. bovis, collected during 3 years from cattle with infectious bovine keratoconjunctivitis (IBK) symptoms, from diverse geographical locations of Argentina, were examined. The LPS and OMP profiles were studied through SDS–PAGE analysis and genotype was determined by PCR-DNA fingerprinting. Genotyping identified five DNA types while analysis of LPS and OMP profiles identified three rough LPS types and three OMP types among the 60 isolates of M. bovis including the three collection strains. None of the three methods employed to assess diversity was discriminating when used alone because the degree of heterogeneity in each group of surface structures was limited, but when data of each typing method were combined, 15 distinct subgroups were determined. This subgrouping was clearly able to differentiate isolates of the same genotype. These typing methods appear to be useful to assess different aspects of the disease such as the diversity within a population of M. bovis associated to epidemic conditions, track the causal agent in an outbreak of the disease, monitoring vaccination programs and studies on virulence. 相似文献
70.