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781.
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A 523 kg Quarter Horse was anesthetized for unilateral eye enucleation. The anesthetic period was unremarkable. During anesthetic recovery the cap on the jugular venous catheter became dislodged. Clinical signs of pulmonary edema associated with moderate arterial hypoxemia subsequently developed. Although pulmonary edema resolved with medical therapy, the day following anesthetic recovery, clinical signs of vestibular disease and blindness developed. Treatment included nasal oxygen insufflation, flunixin meglumine, furosemide, dexamethasone, thiamine, dimethylsulfoxide, antimicrobials, and phenylbutazone. The horse recovered and was discharged from the hospital after 7 days of treatment and was neurologically normal at 6 weeks. While venous air embolism was not confirmed in this case, the catheter cap complication followed by signs of pulmonary edema and neurologic sequelae support the presumptive pathogenesis of this horse's complications. Diagnostic confirmation of air embolism in horses with compatible acute clinical signs should be documented with echocardiography.  相似文献   
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786.
  1. In 2016, the UK government announced plans for a large‐scale Marine Protected Area around Ascension Island, a UK Overseas Territory in the South Atlantic.
  2. To improve baselines for marine life to support ambitious conservation and assess change over time, archives were searched for historical accounts of wildlife from Ascension's discovery in 1501 to the present. For more recent changes, 139 interviews with past and present inhabitants were conducted.
  3. Ascension's marine life has, from first discovery to the present, been consistently remarked upon for its exceptional abundance. Historical sources indicate declines in seabird and turtle populations from human exploitation and introduction of rats and cats. They are recovering with good management, although still below pre‐settlement abundance.
  4. Interviews with residents indicate more recent changes, notably declines in catch per unit of fishing effort at popular shore angling sites, a decline in yellowfin tuna (Thunnus albacares) and increase in Galapagos sharks (Carcharhinus galapagensis).
  5. What is very notable, however, based on the interviews, was that there was no temporal signal suggestive of recent systemic decline, in marked contrast to many parts of the world where recent wildlife declines have been pervasive and steep. Ascension represents a remarkable and immensely important centre of abundance in a sea of depletion and change, warranting full protection for all the island's waters.
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787.
The treatment of amoebic gill disease (AGD) in cultured Atlantic salmon, Salmo salar L., using mucolytic agents has been previously reported. The agent L‐cysteine ethyl ester reduces salmonid mucus viscosity and potentially increases the flushing of the gill. In the present study, the effects of the mucolytic agent N‐acetyl cysteine (NAC) were assessed. Cutaneous mucus from rainbow trout, Oncorhynchus mykiss Walbaum, and Atlantic salmon was shown to have reduced viscosity when mixed in vitro with 100 or 200 μg/mL NAC. Saltwater‐acclimated rainbow trout and Atlantic salmon were fed an oil‐incorporated, NAC‐medicated diet (8 g NAC/kg diet) for up to 24 d and challenged with inoculation of 300 cells/L Neoparamoeba spp., the etiological agent of AGD. Control fish were fed normal oil‐coated pellets and received no NAC. NAC medication failed to reduce the severity of gill lesions associated with AGD even though the mucus viscosity from medicated fish was less than that of controls. Oral NAC medication does not appear to be an effective method for controlling AGD in salmonids despite reducing cutaneous mucus viscosity.  相似文献   
788.
Antibody prevalence for several infectious and parasitic diseases in a population of roe deer (Capreolus capreolus) inhabiting a mixed agricultural landscape (south of France) has been analyzed. Serological analyses with ELISA in 245 animals captured from 2008 to 2012 has been performed. We found a high prevalence of Toxoplasma gondii (46.4%), Chlamydophila abortus (17.27%) and Coxiella burnetii (11.26%) compared to other studies in Europe. Seroprevalence varied strongly among years for T. gondii (27–91%), C. abortus (0–42%) and C. burnetii (0–27%). T. gondii prevalence was lower in juvenile females, compared to juvenile males and adults of both sexes. Other pathogens had low prevalences: Neospora caninum (1.56%), Bovine herpesvirus 1 (1.17%, 2008/09; 1.1%, 2010/11), Mycoplasma agalactiae (1.45%, 2009/10), Mycobacterium avium subsp. paratuberculosis (0.9%) and Slow viruses (CAEV–MVV) (0.15%, 2008/10; 0%, 2011/12). Antibodies to bluetongue virus and pestiviruses were not found in any individual.  相似文献   
789.
The extent of within-field spatial variability of pesticide degradation was characterised in topsoil and subsoil, using the compounds isoproturon, bentazone and mecoprop, which are major contaminants of groundwater and surface freshwater in Europe. Twenty topsoil samples from 0 to 15 cm depth and twenty subsoil samples from 50 to 60 cm depth were collected from a single agricultural field within a 160×90 grid. It was shown that degradation rates of all compounds declined with soil depth. Variability of pesticide degradation rates, pesticide sorption and formation of non-extractable pesticide residues was higher in subsoil relative to topsoil. Furthermore, in the subsoil, there was variation in large scale soil physicochemical composition, which did not occur in topsoil. The greater variability in pesticide degradation rates in subsoil relative to topsoil could be the result of a greater range of degradation kinetics, which could reflect greater spatial variability in the distribution and/or activities of pesticide metabolising communities.  相似文献   
790.
This study investigates the dynamics and viability of a marsh fritillary butterfly Euphydryas aurinia metapopulation in a Belgian successional landscape. Based on capture-mark-recapture and winter nest census data, we first estimated demography (survival and recruitment rates, population size, density dependence) and dispersal parameters (emigration rate, effect of patch connectivity on dispersal, mortality during dispersal). Then using RAMAS/GIS platform, we parameterised a population viability analysis (PVA) model with these parameters to simulate the future of this metapopulation under different scenarios.The metapopulation does not seem viable even if natural reforestation is controlled by adequate management. In its present state, the patch system is not able to sustain enough individuals: due to the large temporal fluctuations in demographic parameters, a carrying capacity far higher than currently would be necessary to limit extinction risk to 1%, suggesting the existence of an extinction debt for the species in Belgium. The situation of E. aurinia appears much worse compared to two other fritillary species threatened in Belgium, for which similar PVA are available. It is therefore urgent to increase the carrying capacity of the patch system. How and where it is achieved are of secondary importance for the gain in viability: improvement of habitat quality through restoration, or increase of habitat quantity via enlargement of existing patches and/or creation of new habitat in the matrix. A regime of management based on regular re-opening and maintenance of habitat patches may be the only guarantee of long-term persistence for this critically endangered species in Belgium.  相似文献   
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