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Jacqueline A. Johnson BVM&S MS Sanghita Bhattacharya PhD Vijay Goel PhD Matthew J. Allen Vet MB PhD 《Veterinary surgery : VS》2011,40(6):720-727
Objective: To define the kinematic motion patterns of the canine cervical spine, with a particular emphasis on identifying differences between the cranial (C2–C4) and caudal (C5–C7) segments, and to determine the significance of coupled motions (CM) in the canine cervical spine. Study Design: Cadaveric biomechanical study. Sample Population: Cervical spines of 8 Foxhounds. Methods: Spinal specimens were considered free of pathology based on radiographic, computed tomography, and magnetic resonance imaging examinations. All musculature was removed without damaging ligaments or joint capsules. Spines were mounted in a customized pure‐moment spine testing jig, and data were collected using an optoelectronic motion capture system. Range of motion, neutral zone and CM in flexion/extension, left/right lateral bending and left/right axial rotation were established. Data were analyzed using mixed‐effects maximum likelihood regression models. Results: Total flexion/extension did not change across the 4 levels. There was no difference between flexion and extension, and no CM was identified. Lateral bending was not different across levels, but tended to be greater in the cranial spine. Axial rotation was ～2.6 times greater in the caudal segments. Lateral bending and axial rotation were coupled. Conclusions: Kinematics of the cranial and caudal cervical spine differed markedly with greater mobility in the caudal cervical spine. 相似文献
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Benz P Maass G Csokai J Fuchs-Baumgartinger A Schwendenwein I Tichy A Nell B 《Veterinary ophthalmology》2011,14(Z1):37-47
Purpose Identification of Encephalitozoon cuniculi (E. cuniculi) as a possible causative agent for cataracts and uveitis in cats. Methods Within a 12‐month study period, cats that were presented with focal anterior cortical or mature cataract and secondary uveitis underwent a complete ophthalmic examination, complete blood count, serum biochemistry, serologic tests for E. cuniculi and tests for feline immunodeficiency virus (FIV), feline infectious peritonitis (FIP), feline leukemia virus (FeLV) and Toxoplasma gondii (T. gondii). PCR for DNA detection of E. cuniculi and T. gondii as well as cytologic examination of aqueous humor after paracentesis and phacoemulsified lens material were also performed. In addition histopathologic examination of the resected anterior lens capsule and attached lens epithelial cells was performed. Serologic testing for antibodies against E. cuniculi was also performed in 100 ophthalmologically healthy cats. Results Eleven (19 eyes) European shorthair cats with a median age of 3.5 years were included. Nine of 11 cats had bilateral cataracts, with 12/19 eyes having focal anterior cortical cataracts and 7/19 eyes having mature cataracts. In 14/19 eyes anterior uveitis was present. All cats had a positive antibody titer (1:80–1:10 000) for E. cuniculi. Encephalitozoon cuniculi DNA was detected by PCR and sequencing in 18/19 lenses and in 10/19 aqueous samples. Five tentative positive results were detected by cytologic examination. Spores were detected in 15/19 samples of lens material with histopathologic staining. Only 2/100 ophthalmologically healthy cats showed a positive antibody titer for E. cuniculi. Conclusion Encephalitozoon cuniculi is a cause of focal anterior cortical cataract and anterior uveitis in cats. 相似文献
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Mathieu Leblond Jacqueline Frair Daniel Fortin Christian Dussault Jean-Pierre Ouellet Réhaume Courtois 《Landscape Ecology》2011,26(10):1433-1446
Efforts in isolating the relative effects of resources and disturbances on animal-distribution patterns remain hindered by
the difficulty of accounting for multiple scales of resource selection by animals with seasonally dynamic drivers. We developed
multi-scale, seasonal models to explore how local resource selection by the threatened forest-dwelling woodland caribou (Rangifer tarandus caribou) was influenced by both broad-scale landscape context and local resource heterogeneity in the intensively managed region
of Charlevoix, Québec, Canada, located on the southern border of the North American caribou range. We estimated resource selection
functions using 23 GPS-collared caribou monitored from 2004 to 2006 and landscape data on vegetation classes, terrain conditions,
and roads. We found evidence of thresholds in road “proximity” effects (up to 1.25 km), which underscores the importance of
including landscape context variables in addition to locally measured variables, and of fitting seasonal-specific models given
temporal variation in the magnitude of selection and optimal scale of measurement. Open lichen woodlands were an important
cover type for caribou during winter and spring, whereas deciduous forests, wetlands, and even young disturbed stands became
important during calving and summer. Caribou consistently avoided roads and rugged terrain conditions at both local and landscape
levels. Landscape context fundamentally constrains the choices available to animals, and we showed that failing to consider
landscape context, or arbitrarily choosing an inappropriate scale for measuring covariates, may provide biased inferences
with respect to habitat selection patterns. Effective habitat management for rare or declining species should carefully consider
the hierarchical nature of habitat selection. 相似文献
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A Polymerase chain reaction was developed to amplify the entire open reading frame of flaB, the gene encoding the endoflagellin subunit protein. The 852 bp amplified products from 23 serovars of the genus Leptospira were subjected to restriction endonuclease analysis and the profiles correlated well with phylogenetic relationships between these serovars. The flaB deoxynucleotide sequences of L. hardjo-bovis, L. hardjo-prajitno and L. grippotyphosa were determined. The deduced primary amino acid sequences of each were highly conserved with only three amino acid residue differences observed. The deoxynucleotide sequences showed genetic drift with alternative bases in the third position of codons. The PCR product derived by amplification of flaB from L. grippotyphosa was cloned into the expression vector pGEX-2T and a recombinant FlaB fusion protein made. As predicted from the deduced amino acid sequences, the recombinant FlaB cross-reacted with heterologous antiserum derived from a rabbit infected with L. hardjo-bovis. 相似文献
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