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Since the emergence of deer farming as an alternative farming enterprise over the past 30 years, there has been an increasing awareness of the potential threat posed by tuberculosis (TB) to domesticated deer. TB, caused by Mycobacterium bovis, has been found in deer in every country involved with deer farming. Different types of TB control policies, which vary from whole-herd depopulation to selective testing and slaughter of reactor animals, have been implemented. Extensive research has been carried out, incorporating modern microbiological and immunological concepts and advanced molecular methodologies, to find new solutions for the eradication of TB from domesticated deer. This work has resulted in valuable new insights into the aetiology, transmission, pathogenesis, diagnosis, prevention and heritability of resistance to M. bovis infection in ruminants. This knowledge has complemented the existing literature database on bovine and human TB and will provide new strategies for improved diagnosis, vaccination and selective breeding to control TB, which should be relevant for human, domestic livestock and wildlife populations. 相似文献
424.
Effect of breed-type and feeding regimen on goat carcass traits 总被引:1,自引:0,他引:1
Meat-type (Boer x Spanish and Spanish) goats from two feeding regimens (feedlot and range) were slaughtered and live and carcass weights were obtained. At 24 h after death, various yield and quality measurements were collected. One side from each carcass was fabricated into major wholesale cuts for dissection into major carcass components. Feedlot goats had heavier (P<.05) live and carcass weights and carcasses that yielded more (P<.05) dissectible fat and lean and less (P<.05) bone, as a percentage of carcass weight, than did the carcasses of range goats. In the feedlot environment, Boer x Spanish goats had greater (P<.05) live weights, carcass weights, actual and adjusted fat thicknesses, carcass conformation scores, and leg circumference scores than did Spanish goats of similar age. The only breed-type differences that were significant after adjusting for live weight using analysis of covariance were that Boer x Spanish goats in the feedlot treatment had greater (P<.05) actual and adjusted fat thickness and carcass conformation than Spanish goats on the feedlot treatment. The Boer x Spanish goat carcass trait advantage could mainly be attributed to their larger size and enhanced capacity for growth. 相似文献
425.
Wildermuth BE Griffin CE Rosenkrantz WS Boord MJ 《Journal of the American Animal Hospital Association》2007,43(6):337-341
The purpose of this study was to compare susceptibilities of ear and skin Pseudomonas spp. isolates to enrofloxacin, marbofloxacin, and ciprofloxacin. Specimens were obtained from dogs examined in a veterinary dermatology referral hospital. Susceptibilities of ear isolates to enrofloxacin, marbofloxacin, and ciprofloxacin were 46.9%, 66.7%, and 75.0%, respectively. Susceptibilities of skin isolates to the same drugs were 76.2%, 81.0%, and 80.0%, respectively. Ear isolates were significantly less susceptible to enrofloxacin than to ciprofloxacin (P=0.021), and ear isolates were significantly less susceptible to enrofloxacin than were skin isolates (P=0.034). When fluoroquinolone resistance was present, ear isolates were significantly less susceptible to enrofloxacin than to ciprofloxacin (P<0.001) and marbofloxacin (P=0.014). 相似文献
426.
Griffin JS Scott DW Erb HN 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2007,54(8):424-427
This study was conducted on 32 dogs with Malassezia otitis externa to determine the effect of heat-fixing otic exudate on cytological analysis. Malassezia infection was confirmed by cytological examination of otic exudate. Otic discharge collected with cotton swabs was then rolled onto glass slides. One slide per dog was heat-fixed prior to staining; the other slide was not heat-fixed. The number of yeast in 10 oil-immersion fields (1000 x magnification) was counted for both slides from each dog. Heat-fixing did not systematically cause either increased or decreased numbers of Malassezia on cytology of otic exudate. 相似文献
427.
Evaluation of magnetic resonance imaging for the differentiation of inflammatory,neoplastic, and vascular intradural spinal cord diseases in the dog
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Amanda E. Masciarelli John F. Griffin IV Geoffrey T. Fosgate Silke Hecht Joseph M. Mankin Shannon P. Holmes Simon R. Platt Marc Kent Theresa E. Pancotto Annie V. Chen Jonathan M. Levine 《Veterinary radiology & ultrasound》2017,58(4):444-453
Magnetic resonance imaging (MRI) is a common test for dogs with suspected intradural spinal cord lesions, however studies on diagnostic performance for this test are lacking. Objectives of this multi‐institutional, retrospective, case‐control study were to estimate sensitivity and specificity of MRI for (1) distinguishing between histopathologically confirmed intradural spinal cord disease versus degenerative myelopathy in dogs, (2) categorizing intradural spinal cord diseases as neoplastic, inflammatory, or vascular; and (3) determining tumor type within the etiologic category of neoplasia. Additional aims were to (1) determine whether knowledge of clinical data affects sensitivity and specificity of MRI diagnoses; and (2) report interrater agreement for MRI classification of intradural spinal lesions. Cases were recruited from participating hospital databases over a 7‐year period. Three reviewers independently evaluated each MRI study prior to and after provision of clinical information. A total of 87 cases were sampled (17 degenerative myelopathy, 53 neoplasia, nine inflammatory, and eight vascular). Magnetic resonance imaging had excellent (>97.6%) sensitivity for diagnosis of intradural spinal cord lesions but specificity varied before and after provision of clinical data (68.6% vs. 82.4%, P = 0.023). Magnetic resonance imaging had good sensitivity (86.8%) and moderate specificity (64.7–72.5%) for diagnosing neoplasia. Sensitivity was lower for classifying inflammatory lesions but improved with provision of clinical data (48.1% vs. 81.5%, P = 0.015). Magnetic resonance imaging was insensitive for diagnosing vascular lesions (25.0%). Interrater agreement was very good for correctly diagnosing dogs with intradural lesions (? = 0.882–0.833), and good (? = 0.726–0.671) for diagnosing dogs with neoplasia. 相似文献
428.
Jason A. Fuerst Jean K. Reichle David Szabo Eli B. Cohen David S. Biller Justin M. Goggin John F. Griffin IV Stacie Aarsvold Susan E. Emerson 《Veterinary radiology & ultrasound》2017,58(1):23-28
Computed tomography (CT) continues to become more widely available for assessment of tumors in dogs, yet there are no studies describing the CT appearance of canine liposarcomas. In this retrospective, multicenter study, CT images of dogs with histologically confirmed liposarcomas were reviewed for size, location, attenuation, contrast enhancement, border definition, internal homogeneity, local infiltration, and mineralization. A total of 24 dogs with 26 liposarcomas were sampled. Mean attenuation was +15.2 (SD = 22.3) Hounsfield units (HU) with a range of –36 to +47.5 HU based on representative regions of interest. Twenty tumors (77%) contained focal areas of fat attenuation. All masses enhanced with contrast medium administration, which is distinct from what has been reported previously in infiltrative lipomas. Other CT features associated with canine liposarcomas included heterogeneous internal attenuation (81%) and lack of a clearly defined capsule (38%) suggesting infiltration of local structures. Six tumors (23%) had foci of mineralization. Findings from the current study indicated that liposarcoma should be considered as a differential diagnosis for mixed‐attenuation, contrast‐enhancing masses in dogs that contain at least one focus of fat attenuation on precontrast images; however, presence of foci of fat attenuation was not a necessary finding for the diagnosis of canine liposarcoma. 相似文献
429.
Cumulative and residual effects of different potato cropping system management strategies on soilborne diseases and soil microbial communities over time
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R. P. Larkin C. W. Honeycutt T. S. Griffin O. M. Olanya Z. He J. M. Halloran 《Plant pathology》2017,66(3):437-449
Soilborne potato diseases and soil microbial community characteristics were evaluated over 8 years in different potato cropping systems designed to address specific management goals of soil conservation, soil improvement and disease suppression. Results were compared to a standard rotation and non‐rotation control in field trials in Maine. Standard rotation consisted of barley underseeded with red clover, followed by potato (2‐year). Soil‐conserving system (SC) featured an additional year of forage grass and reduced tillage (3‐year, barley/timothy–timothy–potato). Soil‐improving system (SI) added yearly compost amendments to SC, and the disease‐suppressive system (DS) featured crops with known disease‐suppressive capability (3‐year, mustard/rapeseed–sudangrass/rye–potato). Systems were established in 2004, evaluated with and without irrigation, and actively managed until 2010, with potato also planted in 2011 and 2012 to examine residual effects. All rotations reduced soilborne diseases black scurf and common scab, and increased yield after one rotation cycle (3 years), but diseases increased overall after two rotation cycles. DS maintained lower soilborne disease levels than all other rotations, as well as high yields, throughout the study. Cropping system effects became more pronounced after multiple cycles. SI system and irrigation both resulted in higher yields, but also higher levels of soilborne disease. Cropping system and irrigation effects were significant even after systems were no longer maintained. Soil microbial community data showed significant changes associated with cropping system, and differences increased over time. Cropping system strategy had significant and lasting effects on soil microbiology and soilborne diseases, and can be used to effectively enhance potato production. 相似文献
430.
Precision Agriculture - On-farm adoption of individual and groups of precision agriculture technologies has grown in the past 15 years. Based on a sample of 545 farm observations collected by the... 相似文献