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101.
Objective To compare isoflurane, sevoflurane and desflurane for inhalant anesthesia in red‐tailed hawks (Buteo jamaicensis) in terms of the speed and characteristics of induction; cardiovascular and respiratory parameters while anesthetized; and speed and quality of recovery. Study design Prospective, cross over, randomized experimental study. Animals 12 healthy adult red‐tailed hawks. Methods Anesthesia was induced with isoflurane, sevoflurane or desflurane in oxygen via face mask in a crossover, randomized design with a 1 week washout period between each treatment. Hawks were tracheally intubated, allowed to breathe spontaneously, and instrumented for cardiopulmonary monitoring. Data collected included heart rate, respiratory rate, end‐tidal CO2, inspired and expired agent, SpO2, temperature, systolic blood pressure, time to intubation and time to recovery (tracking). Recovery was subjectively scored on a 4 point scale as well as a summary evaluation, by a single blinded observer. Results No significant difference in time to induction and time to extubation was noted with the administration of isoflurane, sevoflurane or desflurane. Time to the ability of the bird to follow a moving object with its eyes (tracking) was significantly faster with the administration of sevoflurane and desflurane. All recoveries were scored 1 or 2 and were assessed as good to excellent. No significant difference was noted in heart rate, blood pressure and temperature among the three inhalants. Administration of isoflurane resulted in lower respiratory rates. Conclusions and clinical relevance Overall, although isoflurane remains the most common inhaled anesthetic in avian practice, sevoflurane and desflurane both offer faster time to tracking, while similar changes in cardiopulmonary function were observed with each agent during anesthesia of healthy red‐tailed hawks.  相似文献   
102.
Fish Physiology and Biochemistry - In most fish exhibiting external fertilization, spermatozoa become motile after release into water, triggered by differences between intracellular and...  相似文献   
103.
The feasibility of using recycled granular tire rubber (GTR) to remove molinate from contaminated water bodies was evaluated in this study. Adsorption equilibrium data was well described by a linear isotherm, and the adsorption was completely reversible. Breakthrough curves showed column efficiencies of approximately 40%, based on total capacity, and complete bed regeneration was achieved using clean water. The effluent from the regeneration step was successfully decontaminated using a defined bacterial mixed culture, capable of molinate mineralization. It was shown that this treated water can be used for regenerating a subsequently saturated bed. The GTR adsorbent showed two important features: complete reversibility towards molinate adsorption and stability along successive adsorption/bio-regeneration cycles. Common adsorbents, such as activated carbons and resins, loose performance very quickly under the same conditions, due to irreversible adsorption.  相似文献   
104.
Pigeon circovirus (PiCV) was detected by real-time PCR in cloacal swabs, pharyngeal swabs, and serum samples taken from 74 feral pigeons (Columba livia var. domestica) that were caught at various locations in the city of Ljubljana, Slovenia. PiCV infections were detected in the majority of the tested birds. The highest (74.3%) detection rate was observed in the cloacal swabs and the lowest (31.1%) in serum samples. PiCV DNA was more readily detected in the cloacal swabs, pharyngeal swabs, and serum samples of birds younger than 1 yr. Molecular analysis of partial open reading frame V1 sequences showed that PiCV strains detected in feral pigeons share high nucleotide and amino acid sequence identities with PiCV strains detected in ornamental, racing, meat, and feral pigeons.  相似文献   
105.
Armillaria Species Infesting Vineyards in Northwestern Spain   总被引:1,自引:0,他引:1  
Twelve vineyards in northwestern Spain were studied to assess the incidence of white root rot during 1995 and 1997. In both years, diseased plant material was collected and the Armillaria species responsible was identified on the basis of compatibility testing. Subsequently, restriction fragment length polymorphism (RFLP) analysis of the intergenic spacer region of the nuclear ribosomal RNA gene cluster was used to identify Armillaria species in another 45 symptomatic samples submitted for diagnosis from this area. During 1995, 9 of the 12 vineyards showed white root rot, although in eight cases less than 2% of plants were affected; in the remaining vineyard 17% of plants were diseased. During 1997, 10 of the 12 vineyards were affected and three showed a marked increase in the number of plants with white root rot (to 43%, in the vineyard in which 17% were affected in 1995). The compatibility method detected Armillaria mellea in samples from 10 of the 12 vineyards, and Armillaria gallica in samples from two vineyards. RFLP–PCR analysis detected four restriction patterns corresponding to A. mellea, A. gallica and Armillaria cepistipes: patterns mel 1 (A. mellea, 71% of samples), mel 2 (A. mellea, 18%), gal 1 (A. gallica, 9%), and cep 1 (A. cepistipes, 2%, i.e. a single sample). This is the first report of A. gallica and A. cepistipes infecting Vitis spp. The presence of these two Armillaria species may be related to the fact that the vineyards from which they were isolated were located on cleared forestry sites.  相似文献   
106.
The aim of the present study was to determine the prevalence of Leishmania infantum infection in a wild reservoir host (Canis lupus) throughout an endemic area for the disease (Southern Europe). For that reason, the serum and peripheral blood samples of 33 captive wolves from the European Breeding of Endangered Species Programme (EEP) were analyzed using the enzyme-linked immunosorbent assay (ELISA) and real-time quantitative PCR (qPCR). L. infantum was detected in three samples from Central Portugal and Central and Northern Spain. Even though L. infantum infection in positive samples was low, surveillance of zoonotic leishmaniosis in this population is recommended as the parasite load could be higher in other tissues due to parasite tropism and most of the EEP institutions studied are located in endemic areas for canine leishmaniosis in Europe.  相似文献   
107.
Previous serological surveys have reported the presence of different organisms in cats from Spain but little reports exist about the exact identity of these organisms. The purpose of the study reported here was to assess the presence of DNA of several vector-borne infections in a population of cats from Barcelona area. One hundred blood samples obtained from cats admitted to the UAB-VTH were entered into the study and classified as healthy (n=48) or unhealthy (n=52). EDTA-blood samples were assayed for Leishmania infantum, Ehrlichia spp., Anaplasma spp., Rickettsia spp., Bartonella spp., Hepatozoon spp., Babesia spp. and Theileria spp. DNA by means of PCR amplification and amplicons obtained were sequenced. Prevalence of infectious agents found were Leishmania infantum (3%), Ehrlichia/Anaplasma sp. (1%), Hepatozoon felis (4%) and Bartonella clarridgeiae (1%). Cats being less than 5 years old had more probability of having at less one PCR positive result (P=0.028). The results of this study show a low prevalence of several vector-borne pathogens among cats from Barcelona area. Although higher feline seroprevalences are previously reported, they evidenced exposure and probably overestimate the real or active degree of infection. However, it is important to maintain a high index of suspicion on these infectious diseases, both in sick and asymptomatic cats, and molecular techniques could aid in the identification of these pathogens.  相似文献   
108.
Thirty six isolates of Phoma tracheiphila from Italy, the causal agent of the mal secco disease on Citrus species, were characterised by different molecular tools in comparison with representative isolates of other phytopathogenic Phoma species. These included analysis of the distribution of RAPD and microsatellite markers and sequencing of the internal transcribed spacer (ITS) region of the nuclear rRNA genes. The results obtained with 12 RAPD primers (92 markers) and 7 microsatellite primers (56 markers) suggest that Italian isolates of P. tracheiphila are genetically homogeneous, leading to identical patterns upon amplification with all the tested primers. Accordingly, ITSI-5.8S-ITS2 sequences were highly conserved (98–100% identity along a 544-characters alignment) among all the isolates of P. tracheiphila. A neighbor-joining analysis of ITS sequences of P. tracheiphila in comparison with those of other Phoma species, as well as with alignable sequences from anamorphic and teleomorphic taxa retrieved in BLAST searches, revealed a close relationship between P. tracheiphila and Leptosphaeria congesta. A pair of P. tracheiphila-specific primers was designed on the consensus sequence (555 residues) obtained from the alignment of the newly generated P. tracheiphila ITS sequences. A PCR-based specific assay coupled to electrophoretic separation of amplicons made it possible to detect P. tracheiphila in naturally infected Citrus wood tissue collected from both symptomatic and symptomless plants. The limit of detection was 10 pg of genomic DNA and 5 fg of the ITS target sequence.  相似文献   
109.
Breeding for resistance to rhizomania in sugar beet: A review   总被引:2,自引:0,他引:2  
Currently rhizomania is the most important disease in sugar beet worldwide, and attack can lead to serious yield losses. The disease is caused by beet necrotic yellow vein virus (BNYVV) that is transmitted by the soil-borne fungus Polymyxa betae. Breeding sugar beet cultivars with resistance to rhizomania is regarded as the most appropriate way to enable continued production of this crop in BNYVV-infested fields and also to slow the spread of the disease. Breeding for resistance started with selection by scoring disease symptoms in field experiments. The development of non-destructive greenhouse tests, with determination of the virus concentration in rootlets using ELISA, has greatly improved the efficiency of selection. In this paper the impact of scientific research on the progress in breeding cultivars with resistance to rhizomania is reviewed. This includes the distribution, composition, and pathogenicity of the virus, the sources of resistance to virus and vector, the genetics of virus resistance, progress with breeding methods, and the use of molecular markers and pathogen-derived resistance. The yields and quality characteristics of recently introduced resistant cultivars now equal those of the commercial susceptible cultivars. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
110.

Understanding how species-specific disturbances affect the dynamics of mixed forests is becoming increasingly important due to rapidly changing disturbance regimes. This study estimated the effect of Norway spruce (Picea abies (L.) Karst.) mortality on the disturbance processes in two mixed beech stands of the Western Carpathians that were affected by a bark beetle outbreak. We evaluated the size distribution, fraction of canopy and expanded gaps, the characteristics of gapmakers and the contribution of different species to gap size. The measured canopy gap fraction was <5%, and most canopy gaps were small (<100 m2). Spruce was the most abundant gapmaker, and its share among gapmakers was 3–6 times higher than its share in the canopy. We found that the increase in spruce mortality due to the outbreak resulted in a fine-scale mortality pattern. However, spruce gapmakers did not contribute much to gap area size, as shown by a weak correlation between the number of spruce gapmakers and the area of expanded gaps. Diameter distribution of living versus recently dead trees showed that beech mortality occurred disproportionately in large size classes. However, dead spruce trees were equally frequent in all diameter classes, which means beetles did not exclusively attack larger trees in these stands during the outbreak. We conclude that spruce mortality may have influenced successional processes by giving a competitive advantage to two other species that were not affected by the outbreak, provided that a high deer browsing intensity does not hinder the regeneration of new seedlings.

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