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The genital tracts of 968 slaughtered bulls (46% of which were young post-puberal animals) were examined for defects of a congenital or developmental nature. The overall occurrence of such lesions was 7%. These comprised persistent penile frenulum (0.5%), hypospadias (0.3%), detached urethral process (0.4%), testicular hypoplasia (0.2%), cryptorchidism (0.6%), mesonephric duct abnormalities (1.1%) and bulbourethral cysts, fusion and aplasia (3.6%). Segmental aplasia of the mesonephric duct, not previously recorded in the study area, was found in 4 Shorthorn bulls (0.4%); 2 affected animals were from one herd. In 3 cases of hypospadias (2 from one herd), the urethra communicated with the ventral surface of the penis at the junction of the body and glans through a slit-like orifice. The occurrence of defects observed was generally comparable to that found in bull populations elsewhere but elevated occurrence of several defects in particular herds emphasized the need for further study. 相似文献
3.
Characterizing historical and modern fire regimes in Michigan (USA): A landscape ecosystem approach 总被引:4,自引:0,他引:4
Cleland David T. Crow Thomas R. Saunders Sari C. Dickmann Donald I. Maclean Ann L. Jordan James K. Watson Richard L. Sloan Alyssa M. Brosofske Kimberley D. 《Landscape Ecology》2004,19(3):311-325
We studied the relationships of landscape ecosystems to historical and contemporary fire regimes across 4.3 million hectares in northern lower Michigan (USA). Changes in fire regimes were documented by comparing historical fire rotations in different landscape ecosystems to those occurring between 1985 and 2000. Previously published data and a synthesis of the literature were used to identify six forest-replacement fire regime categories with fire rotations ranging from very short (<100 years) to very long (>1,000 years). We derived spatially-explicit estimates of the susceptibility of landscape ecosystems to fire disturbance using Landtype Association maps as initial units of investigation. Each Landtype Association polygon was assigned to a fire regime category based on associations of ecological factors known to influence fire regimes. Spatial statistics were used to interpolate fire points recorded by the General Land Office. Historical fire rotations were determined by calculating the area burned for each category of fire regime and dividing this area by fifteen (years) to estimate area burned per annum. Modern fire rotations were estimated using data on fire location and size obtained from federal and state agencies. Landtype Associations networked into fire regime categories exhibited differences in both historical and modern fire rotations. Historical rotations varied by 23-fold across all fire rotation categories, and modern forest fire rotations by 13-fold. Modern fire rotations were an order of magnitude longer than historical rotations. The magnitude of these changes has important implications for forest health and understanding of ecological processes in most of the fire rotation categories that we identified.This revised version was published online in May 2005 with corrections to the Cover Date. 相似文献
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Taeymans O Peremans K Saunders JH 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(4):673-684
This review describes the advantages and disadvantages of radiography, ultrasonography, and nuclear medicine in the 2 most frequent thyroid pathologies of the dog: acquired primary hypothyroidism and thyroid neoplasia. Ultrasonography and scintigraphy remain the 2 most indicated imaging modalities for these thyroid abnormalities. However, as in human medicine, computed tomography and magnetic resonance imaging also have potential indications. This is especially the case in the evaluation of the extent, local invasiveness, and local or distant metastases of thyroid neoplasia. Based on experience with different imaging modalities in people, we suggest future directions in the imaging of the canine thyroid gland. 相似文献
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Virginia Buechner-Maxwell Mark Crisman Michael Murray William Ley Geoffrey Saunders Amelia Walton 《Journal of Equine Veterinary Science》1996,16(9):375-379
Transtracheal wash and bronchoalveolar lavage are diagnostic techniques that have been adopted from human medicine for monitoring inflammatory changes in the airway of the horse. Transendoscopic biopsy has also proven to be a valuable tool for obtaining samples of the airway mucosa in human patients. A transendoscopic technique was developed in this study for obtaining a respiratory mucosal biopsy from standing, sedated horses. Six normal adult horses were sampled at eight-week intervals for a total of three sample periods. Horses were monitored for adverse effects of the technique and none were noted. Sample sites were completely healed after eight weeks with no gross or histologic abnormalities. Biopsy samples were 3 to 4 millimeters in diameter, and 17 of 18 samples provided interpretable histological sections. Methods for handling, staining and evaluating tissue were also developed. The results of this study demonstrated that airway mucosal biopsy is a safe, repeatable technique that can be performed in the sedated, standing horse. 相似文献
7.
Martha L. Moon DVM MS Geoffrey K. Saunders DVM MS Robert A. Martin DVM 《Veterinary radiology & ultrasound》1990,31(1):39-41
A 5–year–old cat was presented for pelvic limb weakness. Sclerosis of the vertebral body of T–10 was visible on thoracic radiographs. A compressive lesion at this area was noted on myelography. A tumor was partially removed at surgery, but the cat was killed because of poor postoperative response. Rhabdomyosarcoma was diagnosed at necropsy, with bone marrow necrosis and myelofibrosis, and new bone proliferation of the body of T–10. Causes of bone necrosis are discussed. 相似文献
8.
Advanced imaging modalities are becoming more widely available in veterinary cardiology, including the use of transesophageal echocardiography (TEE) during occlusion of patent ductus arteriosus (PDA) in dogs. The dog in this report had a complex history of attempted ligation and a large PDA that initially precluded device placement thereby limiting the options for PDA closure. Following a second thoracotomy and partial ligation, the morphology of the PDA was altered and device occlusion was an option. Angiographic assessment of the PDA was limited by the presence of hemoclips, and the direction of ductal flow related to the change in anatomy following ligature placement. Intra-operative TEE, in particular real-time three-dimensional imaging, was pivotal for assessing the PDA morphology, monitoring during the procedure, selecting the device size, and confirming device placement. The TEE images increased operator confidence that the size and location of the device were appropriate before release despite the unusual position. This report highlights the benefit of intra-operative TEE, in particular real-time three-dimensional imaging, for successful PDA occlusion in a complicated case. 相似文献
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J Go I Marsh M Gabor V Saunders RL Reece J Frances C Boys LJ Gabor 《Australian veterinary journal》2012,90(12):513-514
Epizootic ulcerative syndrome was diagnosed, and the presence of Aphanomyces invadans confirmed, from an outbreak of clinical disease in wild‐caught bony bream (Nematalosa erebi) from the Darling River near Bourke, in New South Wales, Australia, during 2008. This confirms a significant extension of the agent beyond its historical range. 相似文献