Dermatophilus chelonae in a king cobra (Ophiophagus hannah).

A mass was removed from the left flank of a 10-yr-old male king cobra (Ophiophagus hannah), and histologic examination revealed granulomatous dermatitis with intralesional gram-positive cocci and filamentous bacteria. Fourteen months later, a histologically similar subcutaneous mass was removed from a different site. One year later, a large subcutaneous mass at the first surgical site was removed, and histopathologic examination revealed multiloculated granulomas with intralesional gram-positive cocci. An organism was cultured and identified by 16S ribosomal RNA gene sequencing as Dermatophilus chelonae. After a course of antibiotic therapy, no further lesions were seen for 5 mo.     

An epizootic of chronic regurgitation associated with chlamydophilosis in recently imported emerald tree boas (Corallus caninus).

One hundred and five wild-caught emerald tree boas (Corallus caninus) were added to a collection of 15 others. in Central Florida, during a 4-mo period. Eighty-one boas (67%) developed repetitive regurgitation during the 23-mo period after the initial introduction, and 61 (75%) of these died. Regurgitation occurred 3-4 days after feeding. Prevalence of regurgitation in this population of snakes was 25%/mo (range 0-42%), and incidence was 3.52/mo (range 0-13/mo). The cumulative mortality for those boas developing repetitive regurgitation (61 of 120) during the 23-mo epizootic was 51%. Hematologic findings included anemia and leukocytosis, with lymphocytosis, monocytosis, and azurophilia. Histologic evaluation of the gastrointestinal tract showed multifocal to diffuse lymphoplasmacytic inflammation with granuloma formation and positive immunohistochemical staining for chlamydial antigen. Electron microscopic evaluation of granulomas showed organisms consistent with Chlamydophila sp.     

Five patellar proximodistal positioning indices compared in clinically normal Greenland sled dogs

Patellar luxation in large-breed dogs is associated with abnormal proximodistal patellar positioning. Using a clinically normal population of Greenland sled dogs, measurement reliability and the effect of limb position were compared for five patellar proximodistal positioning indices based on the Insall-Salvati (IS), modified Insall-Salvati (mIS), de Carvalho (dC), patellotrochlear (PT) and Blackburne-Peel (BP) indices. Indices were measured at one knee angle in 44 dogs and two knee angles in 10 dogs. Index susceptibility to error was modelled for different errors in knee angle estimation. Two reported techniques for determining knee angle were compared in a fox hind limb model. Indices dC and PT were significantly affected by knee angle (P<0.001). Error susceptibility was the lowest for IS and the greatest for PT. Intra- and inter-observer agreements were moderate to substantial for all indices. Measurement precision was good for all indices except BP. Patellar ligament laxity significantly affected IS, mIS, dC and BP (P<0.05). Knee angle measurements were technique dependent, with a bias of 9° to 13° and limits of agreement of ±5°. All five indices were reliable, but precision varied. For pre- and post-operative comparison, dC showed less error susceptibility than PT and better precision than BP. An ideal index for clinical use remains to be defined; the best option is dC, although with limitations. The method of knee angle measurement must be defined prior to index measurement and comparison of index values. Index values may vary with species and/or body size.     

A COMPARISON OF NORMAL FELINE THORACIC RADIOGRAPHS MADE IN DORSAL VERSUS VENTRAL RECUMBENCY

Thoracic radiographs of 11 normal cats were made in dorsal (VD) and ventral (DV) recumbency with a vertically directed x-ray beam. These radiographs were compared subjectively and objectively with each other and with an additional pair of radiographs made with the cats in dorsal and ventral recumbency using a horizontally directed x-ray beam. Differences were found between VD and DV thoracic radiographs but they were minimal. In VD radiographs the caudal mediastinum and accessory lobe regïon of the lung were more clearly seen but cardiac shape varied somewhat. In DV radiographs, the appearance of the heart was more constant and caudal lobar pulmonary arteries more clearly seen. The results of this study indicated that both VD and DV radiographs are satisfactory for radiographic examination of the feline thorax     

High-throughput retrotransposon-based fluorescent markers: improved information content and allele discrimination

Background  

Dense genetic maps, together with the efficiency and accuracy of their construction, are integral to genetic studies and marker assisted selection for plant breeding. High-throughput multiplex markers that are robust and reproducible can contribute to both efficiency and accuracy. Multiplex markers are often dominant and so have low information content, this coupled with the pressure to find alternatives to radio-labelling, has led us to adapt the SSAP (sequence specific amplified polymorphism) marker method from a ³³P labelling procedure to fluorescently tagged markers analysed from an automated ABI 3730 xl platform. This method is illustrated for multiplexed SSAP markers based on retrotransposon insertions of pea and is applicable for the rapid and efficient generation of markers from genomes where repetitive element sequence information is available for primer design. We cross-reference SSAP markers previously generated using the ³³P manual PAGE system to fluorescent peaks, and use these high-throughput fluorescent SSAP markers for further genetic studies in Pisum.     

The use of a geographic information system to analyze long-term landscape alteration by beaver

A Geographic Information System (GIS) was used to analyze how beaver (Castor canadensis) have altered the hydrology and vegetation of Voyageurs National Park, Minnesota over a 46-year period. Maps of beaver ponds prepared from 1940, 1948, 1961, 1972, 1981, and 1986 aerial photographs were analyzed with a rasterbased based GIS to determine impoundment hydrology and vegetation distributions for each map date. Overlay and classification techniques were used to quantify hydrologic and vegetation changes between map dates. The GIS was superior to manual methods for some analyses (e.g., area measurement), and indispensible for others (e.g., transition analysis). Total area impounded increased from 1% to 13% of the landscape between 1940 and 1986, as the beaver population increased from near extirpation to a density of 1 colony/km². Most of the impoundment area increase occurred during the first two decades, when 77% of cumulative impoundment area was flooded. Once impounded ≥60% of the area maintained the same water depth or vegetation during any decade. GIS procedures were combined with field data to show that available nitrogen stocks nearly tripled between 1940 and 1986 as a result of beaver impoundment.     

A sequential multi-level framework to improve habitat suitability modelling

Landscape Ecology - Habitat suitability models (HSM) can improve our understanding of a species’ ecology and are valuable tools for informing landscape-scale decisions. We can increase HSM...     

Modeling patch occupancy: Relative performance of ecologically scaled landscape indices

In fragmented landscapes, the likelihood that a species occupies a particular habitat patch is thought to be a function of both patch area and patch isolation. Ecologically scaled landscape indices (ESLIs) combine a species’ ecological profile, i.e., area requirements and dispersal ability, with indices of patch area and connectivity. Since their introduction, ESLIs for area have been modified to incorporate patch quality. ESLIs for connectivity have been modified to incorporate niche breadth, which may influence a species’ ease in crossing the non-habitat matrix between patches. We evaluated the ability of 4 ESLIs, the original and modified indices of area and connectivity, to explain patterns in patch occupancy of 5 forest rodents. Occupancy of eastern gray squirrels (Sciurus carolinensis), North American red squirrels (Tamiasciurus hudsconicus), fox squirrels (Sciurus niger), white-footed mice (Peromyscus leucopus), and eastern chipmunks (Tamias striatus) was modeled at 471 sites in 35 landscapes sampled from the upper Wabash River basin in Indiana. Models containing ESLIs received support for gray squirrels, red squirrels, and chipmunks. Modified ESLIs were important in models for red squirrels. However, none of the models demonstrated high predictive ability. Incorporating habitat quality and using surrogate measures of dispersal can have important effects on model results. Additionally, different responses of species to area, isolation, and habitat quality suggest that generalizing patterns of metapopulation dynamics was not justified, even across closely related species.