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991.
Congenital ocular anomalies in purebred and crossbred Rocky and Kentucky Mountain horses in Canada 总被引:1,自引:1,他引:0
Grahn BH Pinard C Archer S Bellone R Forsyth G Sandmeyer LS 《The Canadian veterinary journal. La revue veterinaire canadienne》2008,49(7):675-681
Multiple congenital ocular anomalies in purebred and crossbred Rocky and Kentucky Mountain horses in Canada are frequently diagnosed with biomicroscopic and indirect ophthalmoscopic examination. In order of frequency detected, these include temporal ciliary epithelial cysts; iridal hypoplasia; prominent corneas; focal temporal retinal degeneration related to ciliary cysts; and, rarely, retinal detachment. A pedigree analysis confirms a dominant mode of inheritance with incomplete penetrance and with a linkage to coat color. 相似文献
992.
Yiannis G. Matsinos Antonios D. Mazaris Kimon D. Papadimitriou Andreas Mniestris George Hatzigiannidis Dimitris Maioglou John D. Pantis 《Landscape Ecology》2008,23(8):945-959
The study of landscape structure and functions, including the underlying ecological and anthropogenic processes has traditionally
relied on visual aspects without considering information of non-visionary cues, e.g. auditory. In this work we applied a complementary
approach for the study of landscapes using qualitative information for the sonic environment. In particular we studied the
qualitative linkages between landscape structure and functions and daily sound patterns. The main objectives were the investigation
of the spatial and temporal variability in sound perception, and the identification of the dominant sound categories (anthropogenic,
biological, geophysical originated sounds) in relation to landscape characteristics. Our results showed significant spatio-temporal
variability in the intensity of different sound categories, which reflects distinct soundscape patterns. Temporal sound variability
reflected the daily cycle of anthropogenic activities and biological processes, whereas the spatial sound viability was mainly
shaped by landscape attributes. The combination of the visual landscape information and its emergent acoustic profile enhances
our perception and understanding of nature and this integrated approach may have many practical applications in landscape
management, monitoring and planning. 相似文献
993.
OFF‐SITE SMARTPHONE VS. STANDARD WORKSTATION IN THE RADIOGRAPHIC DIAGNOSIS OF SMALL INTESTINAL MECHANICAL OBSTRUCTION IN DOGS AND CATS
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Peter G. Noel Anthony J. Fischetti George E. Moore Alexandre B. Le Roux 《Veterinary radiology & ultrasound》2016,57(5):457-461
Off‐site consultations by board‐certified veterinary radiologists benefit residents and emergency clinicians by providing immediate feedback and potentially improving patient outcome. Smartphone devices and compressed images transmitted by email or text greatly facilitate availability of these off‐site consultations. Criticism of a smartphone interface for off‐site consultation is mostly directed at image degradation relative to the standard radiographic viewing room and monitors. The purpose of this retrospective, cross‐sectional, methods comparison study was to compare the accuracy of abdominal radiographs in two imaging interfaces (Joint Photographic Experts Group, off‐site, smartphone vs. Digital Imaging and Communications in Medicine, on‐site, standard workstation) for the diagnosis of small intestinal mechanical obstruction in vomiting dogs and cats. Two board‐certified radiologists graded randomized abdominal radiographs using a five‐point Likert scale for the presence of mechanical obstruction in 100 dogs or cats presenting for vomiting. The area under the receiver operator characteristic curves for both imaging interfaces was high. The accuracy of the smartphone and traditional workstation was not statistically significantly different for either reviewer (P = 0.384 and P = 0.536). Correlation coefficients were 0.821 and 0.705 for each reviewer when the same radiographic study was viewed in different formats. Accuracy differences between radiologists were potentially related to years of experience. We conclude that off‐site expert consultation with a smartphone provides an acceptable interface for accurate diagnosis of small intestinal mechanical obstruction in dogs and cat. 相似文献
994.
995.
Habitat fragmentation,vole population fluctuations,and the ROMPA hypothesis: An experimental test using model landscapes
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George O. BATZLI 《Integrative zoology》2016,11(6):469-482
Increased habitat fragmentation leads to smaller size of habitat patches and to greater distance between patches. The ROMPA hypothesis (ratio of optimal to marginal patch area) uniquely links vole population fluctuations to the composition of the landscape. It states that as ROMPA decreases (fragmentation increases), vole population fluctuations will increase (including the tendency to display multi‐annual cycles in abundance) because decreased proportions of optimal habitat result in greater population declines and longer recovery time after a harsh season. To date, only comparative observations in the field have supported the hypothesis. This paper reports the results of the first experimental test. I used prairie voles, Microtus ochrogaster, and mowed grassland to create model landscapes with 3 levels of ROMPA (high with 25% mowed, medium with 50% mowed and low with 75% mowed). As ROMPA decreased, distances between patches of favorable habitat (high cover) increased owing to a greater proportion of unfavorable (mowed) habitat. Results from the first year with intensive live trapping indicated that the preconditions for operation of the hypothesis existed (inversely density dependent emigration and, as ROMPA decreased, increased per capita mortality and decreased per capita movement between optimal patches). Nevertheless, contrary to the prediction of the hypothesis that populations in landscapes with high ROMPA should have the lowest variability, 5 years of trapping indicated that variability was lowest with medium ROMPA. The design of field experiments may never be perfect, but these results indicate that the ROMPA hypothesis needs further rigorous testing. 相似文献
996.
Bacillus amyloliquefaciens is a kind of non-pathogenic bacteria and widely exists in the environment.During the metabolic process,Bacillus amyloliquefaciens can produce bioactive substances which highly inhibit the activation of multiple pathogens and fungus.In recent years,some bioactive substances are isolated,extracted and purified.With the deeper understanding of Bacillus amyloliquefaciens,it is gradually applied in animal husbandry and aquaculture.This paper summarizes the application and action mechanism of Bacillus amyloliquefaciens in animal breeding industry,it is expected to provide information for further exploration and application. 相似文献
997.
Peter O. Lamuka Francis M. Njeruh George C. Gitao Joseph Matofari Richard Bowen Khalif A. Abey 《Tropical animal health and production》2018,50(5):937-945
A cross-sectional study was conducted among 308 lactating camels selected from 15 herds from three different camel milk clusters in Isiolo County, Kenya, to determine prevalence of bovine and avian tuberculosis using Single Comparative Intradermal Tuberculin Skin test. Seventy-five (75) questionnaires were administered to pastoralists/herders, and focus group discussions were conducted among 3–5 pastoralists/herders selected from each camel herd to collect information on camel husbandry and health management practices and knowledge on tuberculosis in livestock and wildlife. An overall prevalence of bovine and avian reactors was 3.57 and 18.18%, respectively, with bovine and avian reactors for different clusters being 2.38, 3.82, and 4.48% and 25, 17.2, and 11.94%, respectively. There was significant difference (p?<?0.05) in prevalence of bovine and avian reactors between different clusters. There was a negative correction (r?=??0.1399) between herd size and bovine reactors, while there was a positive correlation (r?=?0.0445) between herd size and avian reactors. The respondents indicated that camel herds are exposed to several risk factors like close contact with other herds or livestock or wildlife during grazing and at watering points. Pastoralists have poor knowledge on mode of infection and transmission of bovine or avian tuberculosis. The high prevalence of bovine and avian reactors and pastoralists’ poor knowledge on mode of transmission signify potential risk to public health. 相似文献
998.
Maleko David Ng Wai-Tim Msalya George Mwilawa Angello Pasape Liliane Mtei Kelvin 《Tropical animal health and production》2018,50(7):1653-1664
Tropical Animal Health and Production - The aim of this study was to assess the seasonal effects on quantity and quality of fodder resources and associated utilization practices among smallholder... 相似文献
999.
Interobserver reliability of computed tomographic contouring of canine tonsils in radiation therapy treatment planning
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Keiko Murakami Nicholas J. Rancilio Jeannie Poulson Plantenga George E. Moore Hock Gan Heng Chee Kin Lim 《Veterinary radiology & ultrasound》2018,59(3):357-364
In radiation therapy (RT) treatment planning for canine head and neck cancer, the tonsils may be included as part of the treated volume. Delineation of tonsils on computed tomography (CT) scans is difficult. Error or uncertainty in the volume and location of contoured structures may result in treatment failure. The purpose of this prospective, observer agreement study was to assess the interobserver agreement of tonsillar contouring by two groups of trained observers. Thirty dogs undergoing pre‐ and post‐contrast CT studies of the head were included. After the pre‐ and postcontrast CT scans, the tonsils were identified via direct visualization, barium paste was applied bilaterally to the visible tonsils, and a third CT scan was acquired. Data from each of the three CT scans were registered in an RT treatment planning system. Two groups of observers (one veterinary radiologist and one veterinary radiation oncologist in each group) contoured bilateral tonsils by consensus, obtaining three sets of contours. Tonsil volume and location data were obtained from both groups. The contour volumes and locations were compared between groups using mixed (fixed and random effect) linear models. There was no significant difference between each group's contours in terms of three‐dimensional coordinates. However there was a significant difference between each group's contours in terms of the tonsillar volume (P < 0.0001). Pre‐ and postcontrast CT can be used to identify the location of canine tonsils with reasonable agreement between trained observers. Discrepancy in tonsillar volume between groups of trained observers may affect RT treatment outcome. 相似文献
1000.
Effect of different penetrating and non‐penetrating cryoprotectants and media temperature on the cryosurvival of vitrified in vitro produced porcine blastocysts
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Louise Katherine Bartolac Jenna Louise Lowe George Koustas Christopher Gerald Grupen Cecilia Sjöblom 《Animal Science Journal》2018,89(9):1230-1239
The aim of this study was to determine the most efficient vitrification protocol for the cryopreservation of day 7 in vitro produced (IVP) porcine blastocysts. The post‐warm survival rate of blastocysts vitrified in control (17% dimethyl sulfoxide + 17% ethylene glycol [EG] + 0.4 mol/L sucrose) and commercial media did not differ, nor did the post‐warm survival rate of blastocysts vitrified in medium containing 1,2‐propandiol in place of EG. However, vitrifying embryos in EG alone decreased the cryosurvival rate (55.6% and 33.6%, respectively, p < .05). Furthermore, the post‐warm survival rates of blastocysts vitrified with either trehalose or sucrose as the non‐penetrating cryoprotectant did not differ. There was also no significant difference in post‐warm survival of blastocysts vitrified in control (38°C) media and room temperature (22°C) media with extended equilibration times, although when blastocysts were vitrified using control media at room temperature, the post‐warm survival rate increased (56.8%, 57.3%, 72.5%, respectively, p < .05). The findings show that most cryoprotectant combinations examined proved equally effective at supporting the post‐warm survival of IVP porcine blastocysts. The improved post‐warm survival rate of blastocysts vitrified using media held at room temperature suggests that the cryoprotectant toxicity exerted in 22°C media was reduced. 相似文献