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61.
The collection of epididymal sperm may be a valuable tool for canine reproduction especially since it can enable collection of cells after death of a valuable dog. The aim of the present study was to evaluate the viability of epididymal sperm after freeze-thawing. Epididymides were obtained from four adult dogs by elective orchiectomy. The caudal portion of the epididymides and part of the deferential ducts were squeezed by means of an anatomic clamp into a Petri dish containing either 0.9% saline solution (Group 1) or Ringer solution without lactate (Group 2). Samples were centrifuged at 800 × g for 10 min, the supernatant was removed and the pellet was diluted in one step with a Tris/citric acid/OEP (Orvus Es Paste) extender containing 7% glycerol and subjected to semen freezing. Oocytes were obtained from canine ovaries, after ovariohysterectomy. Only oocytes that were approximately 100 μm in diameter, with a dark ooplasm surrounded by three- or four-well formed cumulus cell layers were used for sperm testing. Frozen semen samples were thawed in a water bath at 70°C for 8 s and analysed at room temperature for sperm motility and velocity. Oocytes were incubated with spermatozoa in humidified atmosphere containing 5% CO2 at 38°C for 18 h. Morphological and functional characteristics of spermatozoa were similar in both groups. However, the percentage of sperm cells bound to oocytes was significantly higher in Group 2 than in Group 1. This result suggests that the Ringer solution without lactate was a more suitable medium for collecting epididymal canine sperm than 0.9% saline. 相似文献
62.
Jeffrey R. Crass MD Ronald L. Genovese VMD James A. Render DVM Errol M. Bellon MD 《Veterinary radiology & ultrasound》1992,33(4):206-216
Ultrasonography and MRI have become valuable tools for imaging of tendon injuries. The current study examines the histopathologic basis for the imaging abnormalities. Five injured equine forelimbs and two normal contralateral limbs were studied with high resolution real time ultrasound and MRI. Histologic sections were made and correlated with the diagnostic images. All lesions were readily seen by both modalities. Lesions characterized by hemorrhage, edma, and cellular infiltration were sonolucent on ultrasound and bright on MRI images. MRI returned to normal as fibrogenesis ensued. Ultrasound images remained abnormal until fibrillar reallgnment occured with completion of the healing process. High resolution real time ultrasound and MRI both accurately reflect the tissue abnormalities in acute tendon injuries. The injured horse does appear to be an effective model for correlative imaging studies of tendon injuries. 相似文献
63.
Roberto A. Santilli Med Vet Luigi V. Bontempi Med Vet Manuela Perego Med Vet Lara Fornai Med Vet Cristina Basso MD PhD 《Journal of Veterinary Cardiology》2009,11(1):47-51
A 5-year-old English Bulldog was presented for acute onset of syncope and fatigue caused by sustained ventricular tachycardia with left bundle block morphology and inferior axis. This arrhythmia had the electrocardiographic features of a ventricular tachycardia arising from the right ventricular outflow tract (RVOT), as described in an experimental canine model and in people. Since a RVOT aneurysm was identified by echocardiography, a segmental form of arrhythmogenic right ventricular cardiomyopathy (ARVC) was suspected. Gross examination of the heart confirmed the bulging of the RVOT and histological examination of the ventricular myocardium revealed segmental involvement of the RVOT with transmural fibro-fatty degeneration. To the authors' knowledge, this is the first reported case of AVRC in an English Bulldog and the first example of segmental AVRC described in the dog. 相似文献
64.
JLA Martins AISB Villaverde AFM Lima PVM Steagall JCP Ferreira CA Taconeli MD Lopes 《Reproduction in domestic animals》2009,44(S2):366-368
The aim of this study was to investigate the impact of a 24-h cooling period prior to freezing on domestic cat epididymal sperm viability. Fifteen tomcats were submitted to routine orchiectomy and sperm samples were retrieved from both epididymides in a Tris–glucose–20% egg yolk extender. For each tomcat, the diluted sperm was split into two equal volumes and cooled to 5°C at a rate of 0.5°C/min; one sample for 60 min (control) and the other for 24 h (cooled). After the cooling period, samples from both groups were frozen using an identical freezing protocol. Sperm samples were evaluated in three different periods: immediately after harvesting, after cooling at 5°C for 24 h (cooled group) and after freezing–thawing of control and cooled groups. Evaluations consisted of sperm motility and progressive status, sperm morphology and plasma membrane integrity (PMI) using two fluorescent probes. After cooling for 24 h, a decrease (p < 0.05) in sperm motility, progressive status and PMI was observed when compared to sperm samples immediately after collection. Comparing the results obtained after thawing, no difference (p < 0.05) was found regarding sperm motility, progressive status, PMI and sperm morphology between control and cooled groups. The results from the present study show that cooling cat epididymal spermatozoa at 5°C for 24 h prior to freezing does not lead to major damage of spermatozoa impairing the freeze–thaw process. 相似文献
65.
PAUL A. KLOC II DVM MA MICHAEL P. KOWALESKI DVM Diplomate ACVS ALAN S. LITSKY MD ScD NANCY O. BROWN VMD Diplomate ACVS ACVIM KENNETH A. JOHNSON MVSc PhD Diplomate ACVS ECVS 《Veterinary surgery : VS》2009,38(1):40-48
Objective— To compare the axial compression stiffness of osteotomized canine tibiae stabilized with Slocum, Securos, or Synthes plates after a tibial plateau leveling osteotomy (TPLO) procedure. Study Design— In vitro, paired comparison of cadaveric tibial constructs subjected to mechanical testing under an axial load. Sample Population— Canine tibiae (n=16 pairs) from skeletally mature male and female dogs of various breeds (18–55 kg). Methods— Tibial pairs (n=16) were randomly assigned to 1 of 2 study cohorts (n=8 pairs/cohort): cohort 1, tibial osteotomy stabilization with a Slocum or a Securos plate, or cohort 2, tibial osteotomy stabilization with a Slocum or a Synthes plate. One tibia from each pair was stabilized with 1 of each plate design assigned to the cohort after TPLO. A 3.2 mm osteotomy gap was maintained during plate application in all constructs. Load and axial displacement were recorded while constructs were loaded to 2000 N in axial compression. Failure loads were not reported because no distinct yield point or failure point was evident within the load range for many specimens. Failure modes were recorded for each construct, and photographs of typical failures were obtained. Stiffness (N/mm) was calculated from load–displacement curves. Paired comparisons of mean stiffness were performed within study groups using a paired t‐test. Significance was set at P<.05. Results— The mean construct stiffnesses for the Slocum (383±183 N/mm) and Securos (258±64.1 N/mm) constructs were not significantly different (P=.164; power=0.566). The mean construct stiffness for the Synthes constructs (486±91.0 N/mm) was significantly greater than that of the Slocum constructs (400±117 N/mm); P=.0468. Modes of failure for the Slocum (16/16) and Securos (8/8) constructs included plastic deformation of the implant with valgus deformity combined with fibular luxation (2/16 Slocum; 1/8 Securos) or fibular fracture (2/16 Slocum; 4/8 Securos). Most Synthes constructs underwent elastic deformation (7/8). One Synthes construct fractured in the saggital plane through the tibial plateau depression at the point of load application. Conclusions— The Slocum and Securos plate/tibia construct have similar stiffness, whereas the Synthes/tibia constructs are significantly stiffer than the Slocum/tibia constructs. Modes of fixation failure observed in this model were consistent with TPLO fixation failures observed clinically. Clinical relevance— Construct stiffness in axial load varies with implant type. Implants that confer higher stiffness to the construct may result in greater fixation stability in tibial metaphyseal osteotomies. 相似文献
66.
67.
Interest in magnetic resonance (MR) imaging as a major diagnostic tool in veterinary clinical medicine is increasing. Most MR studies are performed with the use of contrast enhancement via intravenous injection of paramagnetic gadolinium-containing contrast media. A vast number of publications are available regarding the use of contrast media in humans. The purpose of this paper is to assist practicing veterinary radiologists in understanding mechanisms of MR contrast enhancement. This paper reviews certain aspects of MR contrast enhancement, including physical, chemical and biologic characteristics of most common MR contrast media targeted primarily at the central nervous system (CNS). Authors also describe processes that explain changes in signal intensity on the MR images. 相似文献
68.
Ingrid Allgoewer DVM Susanne Lucas DVM Stephan Albert Schmitz MD 《Veterinary radiology & ultrasound》2000,41(5):413-418
The magnetic resonance imaging appearance of the feline middle ear is described in three healthy cats and in five cats with middle ear disease. Owing to the good spatial resolution, multiplanar slice orientation as well as display high contrast resolution of soft tissue, in particular fluids, MR imaging was helpful prior to surgery. It is superior to radiography which failed to allow identification of the abnormality in two of our five cats. MR imaging for middle ear disease should include dorsal and transverse plane images using T1- and T2-weighted sequences. In the presence of a mass within the bulla or the external ear canal application of contrast medium is helpful. 相似文献
69.
Zahid R. Shah MD Jeffrey R. Crass MD Dubravka C. Oravec MD Errol M. Bellon MD 《Veterinary radiology & ultrasound》1992,33(2):94-100
Foreign bodies in the soft tissues are frequent problems in both veterinary and human medical practice. Radiography has been the principle tool for diagnosis, but is unable to define many foreign bodies. This study was undertaken to compare the sonographic and radiographic visualization for a variety of foreign bodies. Fresh turkey muscle (pectoral and thigh) with skin was used as the soft tissue model. Assorted foreign bodies were introduced 1 cm into the muscle. Materials examined were small wood fragments, steel wire, glass, nails, graphite, rock, BB pellets, and polystyrene plastic. Following introduction of the foreign bodies radiographs were obtained and the specimens were studied sonographically at 5.0 mHz and 7.5 mHz. All foreign bodies were visible with sonography. A bright echo with either acoustic shadowing or reverberations was present for all specimens. Radiographically metallic foreign bodies were visible but wood, some graphite, and plastic were not seen. We conclude that radiography should remain the primary imaging modality for foreign body detection because of its general availability and low cost. If radiography is negative ultrasound can detect and guide the removal of radiolucent foreign bodies. 相似文献
70.
Piper L. Wall DVM PhD † Akella Chendrasekhar MD †Gregory A. Timberlake MD † 《Journal of Veterinary Emergency and Critical Care》1998,8(2):109-115
The accuracy and precision of an end-tidal infrared CO2 monitor and customized capnography tubing system designed to measure gastrointestinal intraluminal CO2 partial pressure (Pi CO2 ) were tested in vitro. Samples were taken from the customized capnography tubing placed in either 5% or 10% CO2 gas at discrete intervals ranging from one minute to twelve minutes. For a given time interval, the tubing PCO2 measurement was a constant fraction of the actual PCO2 (all standard errors < 0.02). For increasing time intervals, the ratio of the tubing PCO2 to actual PCO2 increased logarithmically. In the 5% and 10% CO2 , the regression coefficients were 0.89 and 0.85 for 8 French tubing and 0.99 and 0.91 for 6 French tubing. Beacuase of its accuracy and precision, this system may provide automated gastrointestinal CO2 partial pressure monitoring at short intervals (e.g. 5 minutes), facilitating testing of the role of gastrointestinal Pi CO2 information in treatment algorithms. (Vet Emerg & Crit Care, 1998; 8: 109–116) 相似文献