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排序方式: 共有198条查询结果,搜索用时 15 毫秒
11.
Gabhan Chalmers John McLean D. Bruce Hunter Marina Brash Durda Slavic David L. Pearl Patrick Boerlin 《Canadian journal of veterinary research》2015,79(2):129-135
Pododermatitis is a disease of concern for mink breeders in Canada and worldwide, as it causes discomfort and lowers the breeding rates on farms affected by the disease. Unfortunately, the etiology and pathogenesis of pododermatitis are still unknown. In this study, we compared Staphylococcus spp. and Streptococcus canis isolates from healthy mink with isolates from animals with pododermatitis on 2 farms in Ontario. Almost all hemolytic Staphylococcus spp. isolated were shown to be Staphylococcus delphini Group A by 16S ribosomal ribonucleic acid (rRNA) sequence analysis and polymerase chain reaction (PCR). Pulsed-field gel electrophoresis (PFGE) did not reveal any S. delphini or S. canis clonal lineages specifically associated with pododermatitis, which suggests that these bacteria do not act as primary pathogens, but does not dismiss their potential roles as opportunistic pathogens. While S. delphini and S. canis were the most prevalent bacterial pathogens in mink pododermatitis, they were also present in samples from healthy mink. Arcanobacterium phocae is occasionally isolated from pododermatitis cases, but is difficult to recover with conventional culture methods due to its slow growth. A quantitative real-time PCR was developed for the detection of A. phocae and was tested on 138 samples of footpad tissues from 14 farms. The bacterium was detected only in pododermatitis-endemic farms in Canada and was at higher concentrations in tissues from infected footpads than in healthy tissues. This finding suggests that A. phocae is involved in the pathogenesis of pododermatitis. 相似文献
12.
13.
Acanthocephalan and spargana parasites were identified within a body wall mass during exploratory surgery in a wild green tree snake. Acanthocephalan parasites have not previously been reported in this species. Surgical excision, the treatment of choice, could not be achieved because of the extensive infiltration of the coelomic cavity. 相似文献
14.
Cryptosporidium in farm rabbits is not often recognised due to a low prevalence and asymptomatic course of infection. Nonetheless, incidences of fatal diarrhoeic diseases are frequently noticed in the rabbitries. In this article, we report an outbreak where there was massive mortality among farm rabbits associated with Cryptosporidium infection. The disease was characterised by profuse diarrhoea resulting in the death of rabbits. A pooled faecal sample was screened for a presence of parasites using microscopy methods. In the tested sample no other parasites other than Cryptosporidium oocysts were found. Further identification of the parasite species was performed at a molecular level, using the 18 SSU rRNA, COWP and LIB13 PCR followed by a subtyping at the GP60 gene locus. Sequence analysis of GP60 gene fragment revealed the presence of a novel subtype VbA24 of Cryptosporidium cuniculus. In this outbreak a Cryptosporidium protozoan parasite played a major role in the etiology of the gastrointestinal disorders in rabbits resulting in massive mortality of the infected animals. 相似文献
15.
Shawn D. MacKenzie Jeff L. Caswell Brigitte A. Brisson Luis Gaitero Heather J. Chalmers 《Veterinary radiology & ultrasound》2014,55(5):571-581
A minimally invasive method for delivering injectable therapeutic agents would be desirable for the treatment of intervertebral disc disease in dogs. The purpose of this study was to compare computed tomography (CT), ultrasonography (US), and fluoroscopy modalities for guiding percutaneous injection into canine intervertebral discs. Intervertebral discs of 14 dog cadavers were injected with a gelified ethanol therapeutic agent. Successful injectate placement and injectate leakage were determined based on necropsy inspection of discs. Injection into the nucleus pulposus was successful in 55 of 78 (71%) of all injected discs. Injections guided using CT and fluoroscopy were significantly more successful than US‐guided injections. Odds of successful injection without leakage were greater for CT vs. US (P = 0.0026) but there was no significant difference between CT and fluoroscopy (P = 0.0620). Injection success rates did not differ among vertebral sites or dog cadavers of varying weights. Forty‐nine (63%) of injection sites had injectate leakage outside the disc and 10 of these involved structures within the vertebral canal. The highest rate of injection success with the least amount of leakage was achieved with CT guidance. Findings indicated that CT, fluoroscopy, and US are feasible modalities for guiding percutaneous injection of a gelified ethanol therapeutic agent into the canine intervertebral disc, with moderate to high success rates for different regions of the spine. However, a moderately high rate of injectate leakage occurred outside of the disc and this should be taken into consideration for future safety and efficacy studies. 相似文献
16.
From mid-2004 to mid-2005, several grass carp, Ctenophayngodon idella (Valenciennes), showing evidence of spinal deformity were presented to the Aquatic Animal Health Program, Cornell University. The carp were from three separate locations in New York State. The first case involved several fish from a natural body of water in the Catskill Mountain region of south-eastern New York State. The second was a single affected individual from a private pond in the Fingerlakes region of Central New York State. The third was a single individual from the Cold Springs Harbor Fish Hatchery, Cold Springs Harbor, Long Island. All fish were at least 7 years of age. Radiographs and computed tomography (CT) scans revealed the deformities to be of bony origin. The spinal deformities were characterized by variable amounts of kyphosis, scoliosis and rotation. While it is not possible to determine the specific cause(s) of the lesions, we consider a genetic component as a likely contributor to the observed pathology. 相似文献
17.
Objective To study the efficacy of multiple striate keratotomy for the treatment of persistent corneal erosions suspected to be caused by primary corneal epithelial basement membrane disease.
Design A retrospective study.
Animals 16 dogs, three cats and one Australian dingo.
Procedure A technique called multiple striate keratotomy was used to treat twenty animals suffering from persistent corneal erosions.
Results All persistent corneal erosions healed with only one treatment. Most cases healed within 2 weeks. One case developed a second erosion in the same eye but in a different position to the original erosion.
Conclusions Multiple striate keratotomy is a safe, effective and well tolerated technique for the treatment of persistent corneal erosions thought to be caused by corneal epithelial basement membrane disease. 相似文献
Design A retrospective study.
Animals 16 dogs, three cats and one Australian dingo.
Procedure A technique called multiple striate keratotomy was used to treat twenty animals suffering from persistent corneal erosions.
Results All persistent corneal erosions healed with only one treatment. Most cases healed within 2 weeks. One case developed a second erosion in the same eye but in a different position to the original erosion.
Conclusions Multiple striate keratotomy is a safe, effective and well tolerated technique for the treatment of persistent corneal erosions thought to be caused by corneal epithelial basement membrane disease. 相似文献
18.
Genetic diversity within Australian wheat breeding programs based on molecular and pedigree data 总被引:8,自引:0,他引:8
124 wheat cultivars and breeding lines were screened with 19 microsatellite (SSR) loci generating 160 scorable bands which
were used to construct a genetic distance (GD) matrix. A distance matrix based on coefficient of parentage (COP) scores was
also generated for the cultivars for which good pedigree records were available. The SSR and COP data for 101 of the wheat
cultivars were compared with genetic distance scores obtained using1898 scorable restriction fragment length polymorphism
(RFLP) bands previously generated. Phylograms were generated based on the SSR, RFLP,combined SSR and RFLP and COP data. The
standardised Mantel's Z test showed that the distance matrices generated from all of the data sets were significantly correlated.
Bootstrap analysis showed that, although the SSR and RFLP data were correlated, a large number of SSR loci are required for
determining robust genetic relationships between large numbers of cultivars. In addition, accurate pedigree records are needed
to determine genetic relatedness using COP. The molecular data were also used to determine the level of genetic variability
within breeding programs and to assess the impact of the introduction of semidwarf and other germplasm. The results showed
that the level of genetic diversity in Australian wheat cultivars has increased over time and that in particular, the introduction
of semidwarf germplasm resulted in an increase in the overall diversity.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
19.
Nitrate leaching following autumn and winter application of animal manures to grassland 总被引:2,自引:0,他引:2
Abstract. Under a UK Government consultation procedure announced in 2001, it was proposed that measures agreed within already designated Nitrate Vulnerable Zones (NVZ 's) would be extended to include a considerably increased area of England, Wales and Scotland. Since existing NVZ 's in the UK have included relatively little grassland, it is important to examine how nitrate losses from grassland areas, especially from animal manures, one of the major potential sources of nitrate loss, can be minimized. Experiments were carried out on freely draining grassland soils at four sites (Devon, Hampshire, Shropshire and N Yorkshire) representative of a wide range of climatic and farming conditions across lowland England, over a four year period, 1990/91 to 1993/94. Slurry was applied to experimental plots over a range of times (including June and then monthly, from September to January) at a target rate of 200 kg N ha–1 . Nitrogen leaching over the four years ranged from 0 to >50% of applied slurry N, with the largest losses occurring following applications in the September to November period. The use of a nitrification inhibitor with slurry applied in November failed to provide consistent reduction in nitrate leaching.
A strategy to reduce the risk of N leaching from manures applied to freely draining grassland soils must take account of the characteristics of the manure, in particular its N content, the application rate and the amount of excess rainfall following application. The experimental results suggest that slurry applications to freely draining grassland, in September, October and November should generally be avoided, the rationale for this being dependent on the amount of excess rainfall subsequent to application. Farmyard manure represents a lower risk and does not justify the restrictions on application timing that appear to be necessary with slurry. 相似文献
A strategy to reduce the risk of N leaching from manures applied to freely draining grassland soils must take account of the characteristics of the manure, in particular its N content, the application rate and the amount of excess rainfall following application. The experimental results suggest that slurry applications to freely draining grassland, in September, October and November should generally be avoided, the rationale for this being dependent on the amount of excess rainfall subsequent to application. Farmyard manure represents a lower risk and does not justify the restrictions on application timing that appear to be necessary with slurry. 相似文献
20.
The nation‐building process of Timor‐Leste, the newest nation in Asia, faces significant demographic challenges due to its high population growth, which is the fastest in Asia. The major contributor for this unprecedented growth is the extremely high total fertility rate of Timor‐Leste, among the highest in the world. It is of great concern that if the current fertility rate and its implied population growth continue the population of Timor‐Leste will double in 17 years. The analysis in this paper clearly shows that the current extremely high dependency ratio will decline only marginally in the next 10 years and this will put tremendous pressure on the government to constantly keep up with the increasing number of children entering school every year. However, as the intrinsic value of human resource development feeds back into the overall society and economy, an adequate public investment in knowledge‐producing services at the earliest stages of life and throughout that life has the potential to change the demographic concern of Timor‐Leste into a future demographic dividend. 相似文献