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111.
Groesslinger K Tham T Egerbacher M Lorinson D 《Journal of the American Veterinary Medical Association》2005,226(3):383-386
OBJECTIVE: To determine prevalence and radiologic and histologic appearance of vesicourachal diverticula in dogs without clinical signs of urinary tract disease. DESIGN: Original study. ANIMALS: 50 dogs between 4 months and 17 years old representing 22 breeds that had been euthanatized for unrelated reasons; none of the dogs had a history or clinical signs of urinary tract disease. PROCEDURE: Retrograde positive-contrast radiography was performed, and radiographs were examined for macroscopic diverticula. Necropsy specimens from the urinary bladder vertex were examined by means of light microscopy for diverticula and signs of inflammation. RESULTS: 17 of the 50 (34%) dogs had vesicourachal diverticula, and 1 additional dog had a urachal cyst. Fifteen of the 17 diverticula were macroscopic; surface area of the diverticulum could be measured radiographically in 13 of these dogs and ranged from 1 to 90 mm2. The remaining 2 diverticula were microscopic. Sixteen diverticula were intramural and 1 was extramural. Light microscopic signs of bladder wall inflammation could be detected in 5 dogs, 4 of which had macroscopic diverticula. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that a high percentage of dogs without clinical signs of urinary tract disease may have vesicourachal [corrected] diverticula. Further studies are needed to determine the clinical relevance of vesicourethral diverticula in dogs. 相似文献
112.
Jugl-Chizzola M Spergser J Schilcher F Novak J Bucher A Gabler C Hagmüller W Zitterl-Eglseer K 《Berliner und Münchener tier?rztliche Wochenschrift》2005,118(11-12):495-501
The aim of the study was to test Thymi herba (1.66% v/w essential oil with 39% p-cymene and 32% thymol) in the rearing period of piglets as feed additive. Therefore, two feeding trials were performed with piglet groups ranging from 17 to 22 animals each. Either 10 g of Thymi herba/kg feed (Thymi herba group), 10 mg flavophospholipol/kg feed (flavophospholipol group) or nothing (control group) was added to the animals' feed. No significant differences in the performance parameter daily weight gain among any groups were recorded. No differences concerning feed efficiency or isolation of haemolytic E. coli serotypes were shown. In addition, the antibacterial activity of the essential oil of Thymi herba against 39 haemolytic E. coli isolates from the same weaners was investigated in vitro by disk diffusion, minimum inhibitory concentration and bactericidal concentration testing. In contrast to the feeding results, the essential oil of the thyme batch fed showed antibacterial activity against all haemolytic E. coli investigated. This interesting antibacterial potential of Thymi herba prompts further investigations as to its value as feed additive. 相似文献
113.
Pinitkiatisakul S Mattsson JG Wikman M Friedman M Bengtsson KL Ståhl S Lundén A 《Veterinary parasitology》2005,129(1-2):25-34
The coccidian parasite Neospora caninum is an intracellular protozoan, causing abortion in cattle in many countries around the world. In this study, the protective potential of the major N. caninum surface antigen NcSRS2, expressed in Escherichia coli and formulated into immunostimulating complexes (iscoms), was investigated in an experimental mouse model. The recombinant protein was specially designed for binding to iscoms via biotin-streptavidin interaction. Two groups of 10 BALB/c mice were immunised twice, on days 0 and 28 with iscoms containing either the recombinant NcSRS2 (NcSRS2 iscoms) or similar iscoms with NcSRS2 substituted by an unrelated recombinant malaria peptide (M5) as a control (M5 iscoms). A third group of 10 age-matched BALB/c mice served as an uninfected control group. Immunisation with recombinant NcSRS2 iscoms resulted in production of substantial antibody titres against N. caninum antigen, while the mice immunised with M5 iscoms produced only very low levels of antibodies reacting with N. caninum antigen. After challenge infection with N. caninum tachyzoites on day 69, mice immunised with NcSRS2 iscoms showed only mild and transient symptoms, whereas the group immunised with M5 iscoms showed clinical symptoms until the end of the experiment at 31 days post inoculation. A competitive PCR assay detecting Nc5-repeats was applied to evaluate the level of parasite DNA in the brain. The amount of Nc5-repeats in the group vaccinated with NcSRS2 iscoms was significantly lower than in the control group given M5 iscoms. In conclusion, it was found that the recombinant NcSRS2 iscoms induced specific antibodies to native NcSRS2 and immunity sufficient to reduce the proliferation of N. caninum in the brains of immunised mice. 相似文献
114.
The objective of the study was to investigate the effect of offering supplementary creep feed to piglets during the suckling period on the faecal shedding of haemolytic Escherichia coli bacteria and occurrence of spontaneous post-weaning diarrhoea 0-5 days after weaning. Supplementary creep feed was offered to half of the piglets in 12 litters, from 2 weeks of age until weaning at 4 weeks, and the individual feed contact was recorded by direct observations. It was found that diarrhoea occurrence was associated with faecal shedding of haemolytic E. coli bacteria (p=0.003), specifically E. coli O149 (p=0.004). Occurrence of diarrhoea and faecal shedding of haemolytic E. coli was not associated with creep feeding per se. However, the faecal E. coli O149 shedding occurred significantly less often in piglets that were offered creep feed in the suckling period but only showed limited interest in the feed (i.e. contacted the feed less than or equal to the median level of contact) compared to piglets that had frequent creep feed contact or piglets that had not had access to creep feed at all (p=0.015). Correspondingly, the diarrhoea occurrence tended to be lower in these piglets (p=0.081). Piglets with low creep feed contact during the suckling period ate the same total amount of feed during the 5 days after weaning, however, they ate less feed on days 0-2 after weaning compared to the piglets with frequent creep feed contact and non-creep fed piglets. It is suggested that intestinal function associated with a voluntary low creep feed contact during the suckling period leads to decreased feed intake just after weaning, and thus reduces the intestinal proliferation of E. coli O149 in these piglets. 相似文献
115.
Arbuscular Mycorrhizal Fungi Reduce Development of Pea Root-rot caused by Aphanomyces euteiches using Oospores as Pathogen Inoculum 总被引:5,自引:0,他引:5
Karin Thygesen John Larsen Lars Bødker 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(4):411-419
The effects of the arbuscular mycorrhizal (AM)-fungi Glomus intraradices and Glomus claroideum on pea root-rot development caused by the pathogen Aphanomyces euteiches were investigated in a greenhouse pot-experiment, over the course of three harvests, using oospores as pathogen inoculum. Signature whole cell fatty acids 16:15c and 14:19 were used to quantify AM-fungi and A. euteiches, respectively in both roots and soil. Disease incidence was reduced in AM plants, though this effect was more pronounced in plants with G. intraradices than plants with G. claroideum, and corresponded with a greater mycorrhiza development, both intra- and extra radical in plants with G. intraradices than with G. claroideum. At the final harvest, percentage of root length with oospores was similar in roots of mycorrhizal and non-mycorrhizal plants. Despite the fact that pea root-rot development was only slightly lower in mycorrhizal plants compared to that of non-mycorrhizal plants, in terms of shoot growth and disease severity, mycorrhizal plants suffered less. This suggests a possible mycorrhiza-induced tolerance against pea root-rot. Furthermore, the degree of tolerance induction differed between the two AM-fungi included in the present study. 相似文献
116.
117.
Cannizzo KL McLoughlin MA Mattoon JS Samii VF Chew DJ DiBartola SP 《Journal of the American Veterinary Medical Association》2003,223(4):475-481
OBJECTIVE: To evaluate transurethral cystoscopy and excretory urography for diagnosis of ectopic ureter in female dogs and identify concurrent urogenital abnormalities. DESIGN: Retrospective study. ANIMALS: 25 female dogs. PROCEDURE: Medical records of female dogs that underwent transurethral cystoscopy, excretory urography, and ventral cystotomy were reviewed for signalment, history, physical examination findings, results of bacteriologic culture of urine, and surgical findings. Videotapes of transurethral cystoscopy and radiographic studies were reviewed systematically without knowledge of surgical findings. RESULTS: Ectopic ureters were diagnosed in 24 of 25 (96%) of the dogs, bilaterally in 22 of 24 (91.6%) dogs. Cystoscopic evaluation yielded a correct diagnosis in all dogs when results of ventral cystotomy were used as the diagnostic standard. Cystoscopic evaluation identified a terminal ureteral opening for all ureters. Urethral fenestrations, troughs, striping, and tenting were identified. Abnormalities of the vestibule were identified in all examinations available for review (24/25). The paramesonephric septal remnant and its association with ectopic ureters were identified and characterized by cystoscopy. Radiographic findings were discordant with surgical findings and correctly identified 36 of 46 (78.2%) ectopic ureters and 2 of 4 normal ureters. Hydroureter and renal abnormalities were associated with distal urethral ectopic ureters on radiographic evaluations. CONCLUSIONS AND CLINICAL RELEVANCE: Transurethral cystoscopy was accurate and minimally invasive for identification and classification of ectopic ureters in dogs. Contrast radiography had limitations in diagnosis of ectopic ureters. Cystoscopic findings and associated vaginal and vestibular abnormalities support abnormal embryologic development in the pathogenesis of ectopic ureters. 相似文献
118.
119.
Karin Sorenmo Marissa Samluk Craig Clifford Jennifer Baez Beth Overley Katherine Skorupski Karen Oberthaler Jeffrey Barrett Tom Van Winkle Gabriela Seiler Robert Poppenga Frances Shofer 《Veterinary and comparative oncology》2005,3(1):55-56
Introduction: Canine hemangiosarcoma (HSA) is a fatal malignancy and most dogs die within 6–8 months of diagnosis. The spleen is a common primary site, representing 50% of all cases. These dogs typically present with clinical signs due to tumor rupture and intra‐abdominal dissemination; the abdomen is also the main site of disease progression when these patients fail. Direct delivery of chemotherapy into the abdominal cavity may therefore be a rational approach in this malignancy.
Methods: 14 dogs with stage 2 or 3 splenic HSA were recruited. Doxil at a dose of 1 mg/kg was diluted in saline and administered via ultrasound‐guidance into the abdominal cavity. The dogs were scheduled to receive 4 treatments every 3 weeks. Samples of plasma and abdominal fluid were collected for pharmacokinetic analysis. All dogs were monitored for recurrence and complete necropsies were requested at death.
Results: 8 dogs with stage 3 and 6 dogs with stage 2 HSA were enrolled. All 14 dogs have died, 12/14 due to tumor and 2 from other causes. There was no difference in median survival days between stages (stage 2: 244, stage 3: 125, p = .22). All 12 dogs that died due to tumor‐related causes failed with intra‐abdominal recurrence. Necropsies showed that the dogs in this study had relatively fewer extra‐abdominal metastasis compared to dogs treated with systemic chemotherapy. Pk analysis showed detectable plasma doxorubicin 1 and 2 weeks after treatment.
Conclusion: Direct abdominal administration of Doxil did not prevent intra‐abdominal recurrence; however, it appeared to provide effective systemic coverage. 相似文献
Methods: 14 dogs with stage 2 or 3 splenic HSA were recruited. Doxil at a dose of 1 mg/kg was diluted in saline and administered via ultrasound‐guidance into the abdominal cavity. The dogs were scheduled to receive 4 treatments every 3 weeks. Samples of plasma and abdominal fluid were collected for pharmacokinetic analysis. All dogs were monitored for recurrence and complete necropsies were requested at death.
Results: 8 dogs with stage 3 and 6 dogs with stage 2 HSA were enrolled. All 14 dogs have died, 12/14 due to tumor and 2 from other causes. There was no difference in median survival days between stages (stage 2: 244, stage 3: 125, p = .22). All 12 dogs that died due to tumor‐related causes failed with intra‐abdominal recurrence. Necropsies showed that the dogs in this study had relatively fewer extra‐abdominal metastasis compared to dogs treated with systemic chemotherapy. Pk analysis showed detectable plasma doxorubicin 1 and 2 weeks after treatment.
Conclusion: Direct abdominal administration of Doxil did not prevent intra‐abdominal recurrence; however, it appeared to provide effective systemic coverage. 相似文献
120.
Animal response to landscape heterogeneity directs dispersal and affects connectivity between populations. Topographical heterogeneity
is a major source of landscape heterogeneity, which is rarely studied in the contexts of movement, dispersal, or connectivity.
The current study aims at characterizing and quantifying the impacts of topography on landscape connectivity. We focus on
‘hilltopping’ behavior in butterflies, a dispersal-like behavior where males and virgin females ascend to mountain summits
and mate there. Our approach integrates three elements: an individual-based model for simulating animal movements across topographically
heterogeneous landscapes; a formula for the accessibility of patches in homogenous landscapes; and a graphical analysis of
the plots of the simulation-based vs. the formula-based accessibility values. We characterize the functional relationship
between accessibility values and landscape structure (referred to as ‘accessibility patterns’) and analyze the influence of
two factors: the intensity of the individuals’ response to topography, and the level of topographical noise. We show that,
despite the diversity of topographical landscapes, animal response to topography results in the formation of two, quantifiable
accessibility patterns. We term them ‘effectively homogeneous’ and ‘effectively channeled’. The latter, in which individuals
move toward a single summit, prevails over a wide range of behavioral and spatial parameters. Therefore, ‘channeled’ accessibilities
may occur in a variety of landscapes and contexts. Our work provides novel tools for understanding and predicting accessibility
patterns in heterogeneous landscapes. These tools are essential for linking movement behavior, movement patterns and connectivity.
We also present new insights into the practical value of ecologically scaled landscape indices. 相似文献