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71.
72.
Erythema ab igne, an old and rare disease in the human literature, is an erythematous, often pigmented, reticular, macular dermatosis that occurs at the site of repeated exposure to moderate heat. We identified lesions consistent with erythema ab igne in five dogs, three cats and one silvered langur (Trachypithecus cristatus[Raffles, 1821]). In dogs and cats, the cutaneous lesion distribution typically reflected chronic exposure to moderate heat during lateral or sternal recumbency. The silvered langur developed cutaneous lesions on the dorsal neck from exposure to a heat lamp. Principal clinical lesions consisted of irregular areas of alopecia (7/9) and erythema (7/9), sometimes with hyperpigmentation (3/9). Principal histological features consisted of karyomegaly (9/9) and keratinocyte atypia (4/9), scattered apoptotic or vacuolated basal cells and/or apoptotic keratinocytes (6/9), mild mixed mononuclear interstitial or interface dermatitis (9/9) with adnexal atrophy (8/9), and a variable number of wavy eosinophilic elastic fibres (9/9). The presence of these cutaneous lesions in an animal indicates that the environment should be evaluated for exposure to chronic moderate heat, and the heat source should be eliminated or modified to prevent further exposure and progression of lesions. 相似文献
73.
Leigh Ann Clayton Tracey K Ritzman 《Veterinary Clinics of North America: Exotic Animal Practice》2006,9(3):511-518
A 6-year-old cockatiel was diagnosed with egg binding based on clinical signs, physical examination findings, radiographs, and lack of oviposition. Medical management failed to induce oviposition, and surgical salpingotomy was used to remove the egg from the oviduct. Sterile egg yolk peritonitis was diagnosed based on histology. Postoperative management with leuprolide acetate and husbandary changes successfully prevented egg production for at least 2.5 months after the event. 相似文献
74.
Julie Perkins Alfonso Clavijo Josue I Ortiz Timothy J Salo Hilary J Holland Benjamin J Hindson Mary T McBride 《Journal of veterinary diagnostic investigation》2007,19(2):180-184
Initial results demonstrating the feasibility of a multiplexed liquid array immunoassay for foot-and-mouth disease viral antigen detection and simultaneous serotype differentiation are presented. Serotype-specific antibodies from rabbit and guinea pig hyperimmunesera were isolated and prepared for use in a multiplexed, bead-based assay. The performance of all of the available antibodies as both capture and detector reagents was evaluated in the multiplexed system to establish a combination exhibiting the highest homotypic responses and lowest heterotypic reactions. The multiplexed assay was evaluated against inactivated cell culture supernatant samples of the same subtype as the virus used to raise the capture and detector antibodies. Distinct serotype differentiation was observed, except in the case of serotype SAT1. Subsequently, cell culture supernatant samples from a larger pool of viral subtypes were analyzed. Distinct serotype differentiation was obtained when analyzing cell culture supernatant samples from viral serotypes C, Asia, and SAT3, irrespective of the subtype. However, limitations of the current antibody pairs were realized in some inconclusive results obtained when analyzing samples from a broader range of O, A, and SAT2 subtypes. The results obtained in this initial study will be used to further optimize the assay using polyvalent or monoclonal antibodies and move toward the analysis of clinical samples. 相似文献
75.
Mary Lynn Johnson Jessica M Evoniuk Charles L Stoltenow Katherine I O'rourke Dale A Redmer 《Journal of veterinary diagnostic investigation》2007,19(1):73-77
The objective of this study was to develop a reliable Taqman 5' Nuclease Assay for genotyping sheep for scrapie susceptibility. The sheep prion gene contains 2 single nucleotide polymorphisms (SNPs) that may mediate resistance to classical scrapie, one at codon 136, alanine (A) or valine (V), and another at codon 171, arginine (R) or glutamine (Q). The R allele appears to confer resistance to classical scrapie, with the AA(136) RR(171) genotype the most resistant to scrapie and QR(171) only rarely infected in the US sheep population. The Assays by Design protocol was used for development of probes and primers for codon 136 and Primer Express for codon 171. Commercially available kits were used to isolate genomic DNA from blood or muscle. For validation, 70 SNP determinations for each codon were compared to commercial testing with an error rate of less than 1%. Then, 935 samples from blood (n = 818) and muscle (n = 117) were tested for both codons with 928 successful determinations and only 7 samples (<1% of total samples) that needed repeating. Genotypes were AA QQ (n = 102; 11.0%), AV QQ (n = 28; 3.0%), AA QR (n = 396; 42.7%), AV QR (n = 54; 5.8%), and AA RR (n = 348; 37.5%). Thus, 86% of the sheep tested (n = 798) contained R at codon 171 and were expected to be scrapie-resistant. This new Taqman 5' Nuclease SNP genotyping assay is accurate, easy to perform, and useful in the study of classical scrapie in sheep and its prevention through selective breeding programs to eliminate highly susceptible animals. 相似文献
76.
77.
M Glade Weiser Linda M Vap Mary Anna Thrall 《Veterinary Clinics of North America: Small Animal Practice》2007,37(2):221-36, v
The typical technologies used in veterinary hematology and biochemical analyzers are reviewed, along with associated advantages and disadvantages. Guidelines for implementing a successful in-clinic laboratory are provided, including criteria for system evaluation and expectations for comparative performance evaluations. The more common problems and limitations associated with in-clinic laboratory diagnostics and how to best prevent them are also discussed. 相似文献
78.
The potential negative environmental impact of manure and biological waste (BW) can be minimised at a profit by recycling plant nutrients in the food chain. Current large-scale livestock production, epizootic diseases and increasing globalisation increase the need for biosecurity, to minimise the risk of disease transmission to the food chain. Arable use of manure and BW can inadvertently spread infectious diseases; opinion differs concerning the risk levels. To obtain general acceptance for arable use, a hygienically safe end-product is needed. This paper provides a detailed discussion of treatment alternatives for co-treatment, i.e., mixture before treatment of manure and BW. Composting, anaerobic digestion and ammonia treatment are the three options given. A decision support tool is also presented and discussed. Suitable treatment methods must combine biosecurity aspects with environmental, economic and nutrient recycling aspects to create a beneficial whole-farm approach. 相似文献
79.
Spatial and temporal landscape patterns have long been recognized to influence biological processes, but these processes often
operate at scales that are difficult to study by conventional means. Inferences from genetic markers can overcome some of
these limitations. We used a landscape genetics approach to test hypotheses concerning landscape processes influencing the
demography of Lahontan cutthroat trout in a complex stream network in the Great Basin desert of the western US. Predictions
were tested with population- and individual-based analyses of microsatellite DNA variation, reflecting patterns of dispersal,
population stability, and local effective population sizes. Complementary genetic inferences suggested samples from migratory
corridors housed a mixture of fish from tributaries, as predicted based on assumed migratory life histories in those habitats.
Also as predicted, populations presumed to have greater proportions of migratory fish or from physically connected, large,
or high quality habitats had higher genetic variability and reduced genetic differentiation from other populations. Populations
thought to contain largely non-migratory individuals generally showed the opposite pattern, suggesting behavioral isolation.
Estimated effective sizes were small, and we identified significant and severe genetic bottlenecks in several populations
that were isolated, recently founded, or that inhabit streams that desiccate frequently. Overall, this work suggested that
Lahontan cutthroat trout populations in stream networks are affected by a combination of landscape and metapopulation processes.
Results also demonstrated that genetic patterns can reveal unexpected processes, even within a system that is well studied
from a conventional ecological perspective. 相似文献
80.
The riverscape perspective recognizes the heterogeneous habitat types within the stream corridor as a single, integrated ecological
unit operating across spatial scales. Although there is ample evidence that the riverscape notion is appropriate in understanding
the physical phenomena of stream corridors, significantly less attention has focused on its ecological ramifications. To this
end, we surveyed riverscape habitat variables and bird community characteristics in the Champlain Valley of Vermont, USA.
From the data collected, we used information theoretic methodology (AICc) to model relationships between bird community attributes and key habitat variables across the riverscape. Our models with
the greatest support suggest that riverine bird communities respond to a suite of characteristics; representing a variety
of riverscape habitats at the in-stream, floodplain, and riparian levels. Channel slope, drainage area, percent conifers,
and in-stream habitat condition were among the most influential variables. We found that piscivores are potentially important
indicators of riverscape condition, responding to a host of variables across the riverscape. Our results endorse a holistic
approach to assessing and managing the mosaic of patches in the riverscape and suggest that a riverscape approach has significant
conservation potential. 相似文献