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61.
INJURIES OF THE SAGITTAL GROOVE OF THE PROXIMAL PHALANX IN WARMBLOOD HORSES DETECTED WITH LOW‐FIELD MAGNETIC RESONANCE IMAGING: 19 CASES (2007–2016) 下载免费PDF全文
Sarah J. Gold Natasha M. Werpy Santiago D. Gutierrez‐Nibeyro 《Veterinary radiology & ultrasound》2017,58(3):344-353
Sagittal groove injuries of the proximal phalanx are an important cause of lameness in performance horses. The purpose of this retrospective case series study was to describe standing low‐field magnetic resonance imaging (MRI) characteristics of these injuries in a group of Warmblood horses. Horses with an MRI diagnosis of sagittal groove injuries involving the proximal phalanx and that had follow‐up MRI and clinical outcome information were included. Findings from clinical examinations, diagnostic tests, and other imaging modalities were recorded. All MRI studies were retrieved for re‐evaluation by an experienced, board‐certified veterinary radiologist. A total of 19 horses met inclusion criteria. All horses had MRI lesions consistent with unilateral or bilateral sagittal groove injuries of the proximal phalanx and abnormal mineralization of the sagittal ridge of the third metacarpal/metatarsal bone. Fifteen horses (79%) had concurrent osteoarthritis of the affected metacarpophalangeal/metatarsophalangeal joint. Eighteen horses received conservative therapy and all horses still had osseous abnormalities detected at the time of follow‐up MRI. Thirteen horses (68.5%) were still lame at the time of follow ‐ up, whereas the other six horses (31.5%) had become sound and returned to the previous level of exercise. Findings indicated that, for mature Warmblood horses, acute or chronic injuries of the sagittal groove of the proximal phalanx may have variable standing low‐field MRI characteristics. Based on this sample of 19 horses, findings also indicated that the prognosis for performance soundness in horses diagnosed with sagittal groove injury of the proximal phalanx and concurrent osteoarthritis is poor. 相似文献
62.
Abstract AIM: To describe the pathology of the reproductive tract of red deer stags with active Brucella ovis infection and in stags in which B. ovis infection had resolved. METHODS: Twenty-three red deer stags of varying history were slaughtered and their epididymides and accessory sex glands examined grossly and by histopathology. At the time of slaughter five of the stags had an active B. ovis infection of 24–55 days duration following exposure to infected rams, 10 stags had been experimentally infected with B. ovis by intravenous inoculation 649 days previously and had developed an active infection but the bacterial infection had resolved at least 308 days prior to slaughter, and eight stags had not been exposed to B. ovis at any time. RESULTS: Of the five stags with an active infection, one had gross enlargement of the epididymides that could be detected by scrotal palpation. Histological lesions in all five stags included mild to severe, predominantly non-suppurative epididymitis, vesiculitis, prostatitis and ampullitis, with neutrophil exudation in associated glandular ducts. Additional lesions in the epididymides were spermatic granulomas and epithelial hyperplasia with intra-epithelial cyst formation. Of the 10 stags in which the bacterial infection had resolved, two had gross enlargement of the epididymides. The histological lesions were similar to those in stags with active infection but were generally milder, with increased periductal scar tissue in the epididymides. The lesions seen in stags resembled those seen in rams with B. ovis infection but they were usually less florid and had fewer plasma cells. No gross abnormalities or histopathological lesions were detected in the non-infected stags. CONCLUSIONS: Only a small percentage of red deer stags infected with B. ovis develop lesions of epididymitis that can be detected by scrotal palpation. Gross and histological lesions of the genital tract of stags associated with B. ovis infection are similar to the lesions seen in rams. Lesions in stags persist for >300 days after the bacterial infection has resolved. CLINICAL RELEVANCE: Brucella ovis infection should be considered when there are gross lesions of epididymitis or histological evidence of inflammation in the epididymides or accessory sex glands of red deer stags. Retrospective diagnosis of B. ovis in stags could be achieved by histological examination of the reproductive organs. 相似文献
63.
A "Schrodinger Cat" Superposition State of an Atom 总被引:1,自引:0,他引:1
A "Schrodinger cat"-like state of matter was generated at the single atom level. A trapped 9Be+ ion was laser-cooled to the zero-point energy and then prepared in a superposition of spatially separated coherent harmonic oscillator states. This state was created by application of a sequence of laser pulses, which entangles internal (electronic) and external (motional) states of the ion. The Schrodinger cat superposition was verified by detection of the quantum mechanical interference between the localized wave packets. This mesoscopic system may provide insight into the fuzzy boundary between the classical and quantum worlds by allowing controlled studies of quantum measurement and quantum decoherence. 相似文献
64.
Incorporating indigenous knowledge of fodder trees into small-scale silvopastoral systems in Jamaica 总被引:2,自引:0,他引:2
A study was conducted to identify and explore indigenous knowledge relating to fodder trees and silvopastoral management systems of small-scale farmers in seasonally dry areas of Jamaica. The objectives of the study were to: 1) explore farmers indigenous knowledge relating to fodder trees and silvopastoral management systems in a subtropical dry climate; 2) examine pastoral land-use systems and technologies in current use; and 3) seek to integrate this information into silvopastoral tree fodder systems. Data were gathered via observation and semistructured interviewing. A snowball sampling strategy was used to purposively select all small-scale farmers who had cattle in the Green Park valley for interview.Of forty farmers interviewed, 37 males (92.5%) and 3 females (7.5%) were primary caretakers of cattle. Twenty-seven of 40 farmers (68%) raised cattle to generate income. During extended droughts farmers are forced to look for alternatives to desiccated, overgrazed pasture grasses, including: 1) local travel to harvest sugar cane tops and to cut Guinea grass (Panicum maximum); 2) purchase of bag feed; and 3) harvest and use of tree fodder. Preferred fodder trees were identified as Bacedar (Guazama ulmifolia), Guango (Albizia saman), Breadnut (Brosimum alicastrum) and Quickstick (Gliricidia sepium).Recommended silvopastoral management systems include fodder hedgerows, three strata forage systems, and living fences. In addition, production of indigenous fodder tree species, introducing improved tree fodder species, and planting improved pasture grasses concurrent with cash trees is suggested. 相似文献
65.
66.
Development of utility and location indices for classifying agroforestry species: the case of Rwanda
In a study of farmer knowledge and experimentation of trees and tree cultivation, two categories of farmer consultants were identified, tree experts (n = 44) and control farmers (n = 70), via a two stage process of knowledge ranking and community interviews conducted in three communes in southern Rwanda in 1992. A detailed inventory of tree species was conducted revealing two key characteristics for on-farm trees: multiple utility and high locational flexibility. In order to logically organize the species inventory, two indices, a utility index (UI) and a locational flexibility index (LFI), were developed. The two indices were calculated for each species and then plotted as the axes on a bivariate grid. While few species had both high utility and flexibility indices, the majority that did were indigenous species long used in agroforestry systems (e.g., Euphorbia tirucalli, Vernonia amygdalina, Erythrina abyssinica, etc.). A few naturalized exotics introduced in the 1930s (e.g., Grevillea robusta, Eucalyptus camaldulensis, E. saligna, E. maideni, Cupressus lusitanica and Persea gratissima) were also appreciated for their multiple utility and locational flexibility. Farm sizes varied, averaging 1.27 ha among tree experts and 0.18 ha in the control group. The mean number of species cultivated was significantly higher on tree expert farms (P < 0.01). However, tree density was much lower on tree expert farms (731 trees · ha–1) than on control farms (1,689 trees · ha–1). Competitive species were found primarily on larger farms, whereas smaller farms were associated with species of greater UI and LFI. Farmers demonstrated deliberate and rational choices about which trees to plant in accordance with each species utility and flexibility in relation to land availability. 相似文献
67.
H Ülker M Küçük A Ylmaz M Yörük L Arslan DM deAvila JJ Reeves 《Reproduction in domestic animals》2009,44(1):37-43
This study was designed to evaluate the effectiveness of recombinant Ovalbumin-LHRL (OL) immunization on changes in testicular size, histological appearance and testosterone production in buck kids. Thirty native buck kids at 18 weeks of age were divided into three groups, control (n = 10), immunization (n = 10) and castration (n = 10) groups. Immunized animals received OL protein generated by recombinant DNA technology. Ultrasonographic and histological examinations of the testes were performed. Animals were slaughtered at 44 weeks of age. Semen and epididymides were evaluated for the presence of sperm cells. Immunized animals generated anti-LHRH antibodies. Testosterone production, testicular and accessory glands development and sperm production were suppressed in the immunized animals (p < 0.01). Semineferous tubule diameters decreased (p < 0.01), basal membrane of the tubule was thickened and hyalinized in immunized kids. Immunization affected ultrasonographic appearance of the testes drastically. While testes of control animals gained their normal ultrasonographic appearance as the age increased, immunized animals had uniform hypoechogenic testicular structure as observed at 18 weeks of age until slaughter. Simultaneous histological and ultrasonographic evaluations indicated that the changes in testicular histology could partly be monitored via ultrasonographic imaging; nevertheless, it is difficult to claim that ultrasonographic image reflects the exact changes in such instances. In conclusion, these results indicate that recombinant OL fusion protein is effective in immunocastration in buck kids and has a potential to be used as an alternative to physical castration. Further researches should be conducted to help assessing reproductive status of testes from ultrasound images. 相似文献
68.
Giot L Bader JS Brouwer C Chaudhuri A Kuang B Li Y Hao YL Ooi CE Godwin B Vitols E Vijayadamodar G Pochart P Machineni H Welsh M Kong Y Zerhusen B Malcolm R Varrone Z Collis A Minto M Burgess S McDaniel L Stimpson E Spriggs F Williams J Neurath K Ioime N Agee M Voss E Furtak K Renzulli R Aanensen N Carrolla S Bickelhaupt E Lazovatsky Y DaSilva A Zhong J Stanyon CA Finley RL White KP Braverman M Jarvie T Gold S Leach M Knight J Shimkets RA McKenna MP Chant J Rothberg JM 《Science (New York, N.Y.)》2003,302(5651):1727-1736
69.
ABSTRACT Both typical late season stem infections and atypical early season rosette infections of canola, a relatively new crop in the southeastern United States, were caused by Sclerotinia sclerotiorum. The 51 DNA fingerprints (from 71 isolates) did not match any fingerprints from previous studies of canola or other crops. Single locus haplotypes from nuclear DNA sequences included 18 in the intergenic spacer (IGS) of the rRNA repeat, four in 44.11, six in translation elongation factor 1alpha, three in calmodulin (CAL), and two in chitin synthase 1. Contingency permutation testing for associations of infection type with DNA fingerprint, single- or multilocus haplotype, or hierarchically nested clades based on single locus haplotypes found significant association of haplotype with mycelial compatibility group and DNA fingerprint for all loci except CAL. Significant association of IGS haplotypes with symptom type was detected in one pathogen population. Southeastern U.S. canola was infected by both recently evolved, geographically dispersed pathogen genotypes and older, indigenous genotypes (Carbone and Kohn, 2001. Mol. Ecol. 10:947-964). Indigenous haplotypes are infection-type generalists, and the most frequently isolated from rosette infections. In contrast, haplotypes from the most recently evolved, dispersed population were associated one-to-one with infection type, with only the most recently evolved haplotypes infecting rosettes. 相似文献
70.
Wagner B Glaser A Hillegas JM Erb H Gold C Freer H 《Veterinary immunology and immunopathology》2008,122(1-2):46-56
West Nile virus (WNV) is a zoonotic pathogen of global importance. In horses with neurological signs, detection of WNV-specific immunoglobulin M (IgM) in serum is widely used to identify clinical cases of WNV encephalitis. Here, we describe the development of two monoclonal antibodies (mAbs) to equine IgM which were used in a WNV IgM-specific enzyme-linked immunosorbent assay (ELISA). Their performance was compared to an established assay based on polyclonal anti-IgM. Check test serum samples from the National Veterinary Service Laboratory (NVSL) were used to evaluate the performance of the three anti-IgM antibodies. The anti-IgM 1-22 mAb correctly identified all NVSL samples. Both the polyclonal antibody and monoclonal anti-IgM 2B-63 identified eight out of ten samples correctly. The three assays were then compared using serum samples from clinically healthy animals (n=33) and horses with neurological signs (n=21). High Spearman rank correlations (0.76-0.86) were found among the ELISA results. Inter-test agreements (weighted kappa) for assay interpretation resulted in strong agreement (0.95) of the results obtained by the mAbs and moderate agreements when monoclonal and polyclonal anti-IgM-based assays were compared. To determine the analytical sensitivities of anti-WNV IgM detection, serial dilutions of WNV IgM-positive serum samples were analyzed. The highest sensitivity was obtained by using the anti-IgM 1-22 mAb to capture IgM from equine serum. In conclusion, the use of monoclonal anti-IgM antibodies can improve the sensitivity of IgM detection in the acute phase of WN disease. 相似文献