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31.
Bradley J O'Hagan Shane R Raidal 《Veterinary Clinics of North America: Exotic Animal Practice》2006,9(3):729-733
The surgical removal of retrobulbar hemangioma is described in a mature fantail goldfish (Carassius auratus) with a 6-week history of a swollen right eye.The fish was anesthetized using alfaxalnone at a concentration in the water of 5 mg/L to facilitate fine-needle aspiration and surgical removal of the eye. The fish was treated with enrofloxacin 5 mg intraperitoneally and recovered with major buoyancy deficits that corrected 20 minutes after treatment with methadone at a dose of 0.4 mg intramuscularly. Histologic examination of the excised tissue demonstrated that the tumor was a compact hemangioma. 相似文献
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Yuri Zharikov David B. Lank Falk Huettmann Russell W. Bradley Nadine Parker Peggy P. -W. Yen Laura A. Mcfarlane-Tranquilla Fred Cooke 《Landscape Ecology》2006,21(1):107-120
We studied habitat selection and breeding success in marked populations of a protected seabird (family Alcidae), the marbled
murrelet (Brachyramphus marmoratus), in a relatively intact and a heavily logged old-growth forest landscape in south-western Canada. Murrelets used old-growth
fragments either proportionately to their size frequency distribution (intact) or they tended to nest in disproportionately
smaller fragments (logged). Multiple regression modelling showed that murrelet distribution could be explained by proximity
of nests to landscape features producing biotic and abiotic edge effects. Streams, steeper slopes and lower elevations were
selected in both landscapes, probably due to good nesting habitat conditions and easier access to nest sites. In the logged
landscape, the murrelets nested closer to recent clearcuts than would be expected. Proximity to the ocean was favoured in
the intact area. The models of habitat selection had satisfactory discriminatory ability in both landscapes. Breeding success
(probability of nest survival to the middle of the chick rearing period), inferred from nest attendance patterns by radio-tagged
parents, was modelled in the logged landscape. Survivorship was greater in areas with recent clearcuts and lower in areas
with much regrowth, i.e. it was positively correlated with recent habitat fragmentation. We conclude that marbled murrelets
can successfully breed in old-growth forests fragmented by logging. 相似文献
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Context
North American grassland songbird populations have declined significantly due to habitat loss and fragmentation. Understanding the influence of the surrounding landscape on prairie fragment occupancy is vital for predicting the fate of grassland birds in these heavily altered landscapes.Objectives
We examined the relative importance of local and landscape variables on grassland bird occupancy of prairie fragments using a focal-patch study. We also investigated the spatial scale at which landscape variables were most influential.Methods
We surveyed birds on 29 unplowed prairie fragments in western Minnesota and eastern North and South Dakota. We quantified local habitat on the fragment using vegetation surveys and aerial photographs and the landscape surrounding the fragment out to 4 km using aerial photographs. We analyzed occupancy using multi-model approaches applied to multiple logistic regression.Results
Of 38 species encountered, nine were neither too rare nor too abundant to be analyzed. Predictors of patch occupancy were unique for each bird species, yet general patterns emerged. For eight species, landscape variables were more important than local variables. Mostly, those landscape variables measured configuration (e.g., edge density) and not composition (e.g., percent cover of a particular matrix element). Landscape effects were mostly from variables measured at the greatest extents from the prairie fragment.Conclusions
Using a focal-patch study design we demonstrated the importance of the surrounding landscape, often out to 4 km from the fragment edge, on prairie occupancy by grassland birds. Effective management of grassland songbirds will require attention to the landscape context of prairie fragments.36.
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38.
The effectiveness of a morantel sustained-release bolus (MSRB) in controlling gastrointestinal nematode infections was determined in 70 Holstein heifer calves with no prior grazing experience. Calves were allotted to 2 treatment groups and were maintained in Florida during the grazing season on divided pastures of equal area. One MSRB was administered to each calf in 1 group at the time of turnout onto spring pasture, whereas calves in the other group remained as nonmedicated controls. By the end of the grazing season, treatment resulted in significantly (P less than 0.05) lower worm burdens and significantly improved weight gains. The MSRB-treated calves were able to reach breeding weight 2 to 4 weeks earlier than did nonmedicated calves. 相似文献
39.
Perceptions and opinions of pet owners in the United Sates about surgery,pain management,and anesthesia in dogs and cats 下载免费PDF全文
Bradley T. Simon DVM MSc DACVAA Elizabeth M. Scallan DVM MBA MS CVA CCRP Dirsko J. F. Von Pfeil DVM DACVS DECVS DACVSMR Daniel T. Boruta DVM DACVAA Rick Wall DVM DACVSMR CCRP Belle M. Nibblett DVM MVSc DACVIM O Odette DVM DACVAA Guy Beauchamp PhD Paulo V. Steagall DVM MSc PhD DACVAA 《Veterinary surgery : VS》2018,47(2):277-284
40.
Many authors suggest the need to define ‘sustainable development’in operational terms. This paper looks at the problems ofattempting to ask whether peasant farming systems are sustainable.Any attempt at sustainability assessment needs to consider issuesrelated to the selected indicators or performance criteria, spatialscale or boundaries, and temporal scale. While there is certainlya need for more rigorous analysis of sustainability issues, thereis limited outlook for an approach based on indicators. Even if themany purely technical problems associated with specific indicatorscan be surmounted, will accurate bio-physical data advance ourknowledge about sustainability? Peasant systems arepolitically-guided management systems, whose boundaries are the state,not the field or the farm. Given the dynamic nature of peasant farmingsystems, where do we draw the line in assessing sustainability?Attempts at sustainability assessment 100 years ago or even 20–30years ago would have been completely superseded by events. We drawattention to the system as a whole, to a web of interconnections,causes and effects – of varying significance over both time andspace. 相似文献