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A total of 74 Staphylococcus pseudintermedius strains were isolated from the 99 clinical cases of canine pyoderma or chronic otitis in our veterinary teaching hospital during May 2006-February 2008. In this study, we examined the genetic distribution of staphylococcal pyogenic toxins such as staphylococcal enterotoxins A (sea), B (seb), C (sec), D (sed), E (see), and toxic shock syndrome toxin 1 (tst) as well as the previously characterized S. intermedius exfoliative toxin (siet) among those isolates. The polymerase chain reaction analyses with the toxin gene-specific primers revealed that 18 (24.3%) of 74 S. pseudintermedius isolates carried the sec genes, but none of the sea, seb, sed, see and tst genes. Further DNA sequencing analysis of the amplified sec genes revealed that they all belonged to the canine type C staphylococcal enterotoxin (SEC(canine) ) whose superantigenic activity has been demonstrated. In addition to the sec(canine) genes, our polymerase chain reaction results showed that all the 74 isolates carried the siet gene. Since both SEC(canine) and SIET toxins are known to be biologically active, it would be interesting to investigate how those toxins are involved in the pathogenesis of the canine diseases by S. pseudintermedius such as pyoderma or chronic otitis.

Administration of immunosuppressive doses of glucocorticosteroids is the traditional primary treatment in necrotizing meningoencephalitis (NME) in dogs. However, response is variable and clinical signs often recur quickly with tapering dosage. Prognosis is poor and long-term therapy causes many complications. In the present study, we compared the long-term effects of combination (cyclosporine plus prednisolone) therapy with sole prednisolone therapy in management in dogs with NME. All NME cases in this study were examined with magnetic resonance imaging and cerebrospinal fluid analysis, and confirmed by histopathologic examination. The mean survival time of combination therapy group was 305.7 +/- 94.7 days. The mean survival time of sole prednisolone therapy group was 58.3 +/- 30.5 days. This case report demonstrates that combination treatment of cyclosporine with prednisolone is more effective in survival time than administration of only prednisolone in NME cases.

A 4-month-old sexually intact female Roborovski hamster (Phodopus roborovskii) was evaluated because of multiple firm subcutaneous nodules in all 4 feet. The nodules were first identified 1 month earlier and had rapidly increased in size. The hamster was reared alone in a plastic cage with no toys or ornaments. The hamster was fed a commercial diet, and its bedding consisted of pine wood shavings.

Stem cell therapy is being special premise for various renal diseases. However, there is limited literature on localization and pathologic and functional effects of allogenic mesenchymal stem cells (MSCs) in healthy dogs. Two healthy dogs were included in this study. Canine MSCs (cMSCs) were cultured from canine bone marrow and incubated with superparamagnetic iron oxide (SPIO) for in vivo cell tracking via MR imaging. The dogs were given the MSC (3 × 10(6) cells) into a renal artery via femoral artery catheterization. Follow-up serial renal assessments included ultrasonography and MRI, serum chemistry, urine analysis, and renal clearance tests. The dogs were euthanized at days 8 and 35 respectively for histopathologic evaluation of kidney. Strong hypointensity in MRI was detected in the treated renal cortex the day after cMSCs infusion. However they disappeared from MR image by the 8th day. Of the serum chemistry tests, serum hepatic enzymes (ALT, AST) were significantly elevated for one week after cMSCs treatment. Histopathological findings also revealed infiltration of SPIO-containing cells into the parenchyma of kidney. On 35th day, histopathology, glomerular atrophy, tubular necrosis, and mineralization were found in the subcapsular cortex, with fibrosis of the interstitial tissues. In vivo MRI studies of stem cells were useful in determining the sequential location of stem cells in the renal parenchyma of healthy dogs. Allogenic stem cells administered via renal artery caused inflammation, tubular necrosis, mineralization, and fibrosis without functional complications.

The purpose of this study was to describe relevant canine brain structures as seen on T2-weighted images following magnetic resonance (MR) imaging at 7 T and to compare the results with imaging at 1.5 T. Imaging was performed on five healthy laboratory beagle dogs using 1.5 and 7 T clinical scanners. At 1.5 T, spin echo images were acquired, while gradient echo images were acquired at 3 T. Image quality and conspicuity of anatomic structures were evaluated qualitatively by direct comparison of the images obtained from the two different magnetic fields. The signal-to-nose ratio (SNR) and contrast-to-noise ratio (CNR) were calculated and compared between 1.5 and 7 T. The T2-weighted images at 7 T provided good spatial and contrast resolution for the identification of clinically relevant brain anatomy; these images provided better delineation and conspicuity of the brain stem and cerebellar structures, which were difficult to unequivocally identify at 1.5 T. However, frontal and parietal lobe and the trigeminal nerve were difficult to identify at 7 T due to susceptibility artifact. The SNR and CNR of the images at 7 T were significantly increased up to 318% and 715% compared with the 1.5 T images. If some disadvantages of 7 T imaging, such as susceptibility artifacts, technical difficulties, and high cost, can be improved, 7 T clinical MR imaging could provide a good experimental and diagnostic tool for the evaluation of canine brain disorders.

A 6-year-old, intact female Maltese dog was presented with generalized seizures. Based on the neurological and physical examinations, intracranial lesion was suspected. Magnetic resonance imaging (MRI) of the brain was performed at three different magnetic field strengths (0.2, 1.5 and 7.0 T). Diffuse hypo- and hyperintense lesions involving the left caudate nucleus and internal capsule to the cranial diencephalon were identified on T2-weighted images. The detailed anatomical locations, the inflammatory and hemorrhagic changes of the lesions could be detected more apparently at 7.0 T. Histopathologically, granulomatous meningoencephalitis (GME) was diagnosed. This is the first case describing histopathologically confirmed GME lesions using 0.2, 1.5 and 7.0 T clinical MR scanner.

The effects of electroacupuncture (EA) on intraocular pressure (IOP) and hemodynamic parameters were evaluated in isoflurane anesthetized 10 (5 males, 5 females) normal mongrel dogs (8.1-9.8 kg, 6-8 years old). After determination of baseline IOP and hemodynamic parameters (cardiac index, systolic arterial pressure, diastolic arterial pressure, heart rate and systemic vascular resistance index), EA was applied at 3 acupoints (LI-4, LIV-3 and GB-37) for 20 min. After the EA treatment, IOP was significantly decreased in the both eyes (p

Three dogs were presented to us for evaluation of cardiac problems. Electrocardiographic recordings revealed severe tachyarrhythmia and atrial fibrillation with ventricular tachycardia in 2 of the 3 dogs. The echocardiographic findings of the 3 dogs revealed markedly decreased fractional shortening and a marked increase in E-point septal separation. Based on the results of electrocardiographic and echocardiographic evaluation, the 3 dogs were diagnosed as dilated cardiomyopathy (DCM). The dogs were treated with conventional cardiac medication, but cardiac function did not improve and the clinical signs remained. We subsequently attempted treatment with granulocyte-colony stimulating factor (G-CSF; 10 microg/kg, subcutaneously). The specific purpose of G-CSF therapy for DCM was to improve cardiac function and a significant improvement in cardiac function was confirmed. The three dogs had no treatment side effects. This case report suggests that G-CSF might have therapeutic effects for medically refractory DCM in dogs.

An 11-year-old, castrated male Miniature Poodle dog was referred due to daily plant eating followed by vomiting for 7 years. Each time the dog went out for a walk, he had been munched grass, and then vomited. There were no abnormal findings on medical examinations. Through behavior examination and consultation, we diagnosed this dog as having a plant eating problem. Because we assumed that the dog had eaten plants to supply of dietary deficiency or relieve digestive problems, advised the owner to discontinue supplying previous diet and to feed high-fiber diet. On the follow up, the owner said that the dog had not eaten plants and vomited from 3 days after initial dietary change. The dog has not shown any clinical signs for 13 months. This clinical finding shows a possibility that deficient diet, especially fiber, relates to the plant eating behavior of a dog.

The hemodynamic effects of vasopressin of high/low doses on dogs were investigated using experimentally induced hemorrhagic shock model. Experimental groups were categorized according to administered doses of vasopressin (0.1, 0.4 and 1.6 IU/kg) and hemodynamic parameters were measured before and after the graded-dose administration of vasopressin. Administration of high- and middle-dose vasopressin (0.4 and 1.6 IU/kg) showed superior increase in blood pressure and systemic vascular resistance, compared with those of low-dose one (0.1 IU/kg). Results of systolic arterial pressure and mean arterial pressure in 1.6 IU/kg-administered group revealed lower efficacy than that in 0.4 IU/kg group in spite of administration of higher dose. This study demonstrates that 0.4 IU/kg of vasopressin can be used as the most effective dose for improving hemodynamic condition in the decompensatory phase of hemorrhagic shock in dogs.

In the present study, we tested the hypothesis that vasopressin administration prior to crystalloid resuscitation can be used to improve hemodynamic and oxygen delivery functions. Hemorrhagic shock was experimentally induced by maintaining mean arterial pressure at 60 mmHg for 30 min in sixteen healthy dogs weighing from 8 to 10.6 kg. Vasopressin was administered and then volume resuscitation was performed for the 6 dogs of V-C group, while vasopressin was administered at the end of volume resuscitation in the 5 dogs of C-V group. The control group (n=5) was administered 0.4 IU/kg of vasopressin after induction of shock without fluid resuscitation. In all groups, hemodynamic parameters were measured pre- and post-hemorrhage and for 60 min after fluid resuscitation. The dogs in V-C group had substantially increased systolic arterial pressure (SAP) for 60 min and improved pulmonary capillary wedge pressure (PCWP), cardiac output (CO), oxygen delivery, and oxygen consumption indexes compared with C-V and control groups. Diastolic pressure and systemic vascular resistance was significantly lower in the V-C group than those in the C-V and control groups (P

The effect of vasopressin was compared with that of the established vasopressor epinephrine in experimentally induced hemorrhagic shock. After rapid crystalloid resuscitation in a ratio of three volumes of 0.9% saline to one volume of blood (3:1 crystalloid resuscitation), six dogs were given 0.4 IU/kg vasopressin and another six dogs were given 0.1 mg/kg epinephrine. Five dogs in the control group were given fluid resuscitation in the same manner as above without administration of any drugs. Administration of vasopressin increased diastolic arterial pressure (DAP) from 45.0 +/- 4.9 to 91.2 +/- 9.6 mmHg within 5 min, compared with epinephrine from 46 +/- 4.0 to 51.8 +/- 7.7, and control from 47.3 +/- 7.5 to 46.3 +/- 7.3. Systolic arterial pressure (SAP) did not increase significantly following vasopressin compared with epinephrine and control group. Results of DAP and systemic vascular resistance index (SVRI) suggested that vasopressin administration was vasoconstrictive after fluid resuscitation in decompensatory hemorrhagic shock in dogs, whereas epinephrine did not compared with control. In addition, epinephrine did not affect the cardiac index (CI) and SVRI, while a significant decrease in CI and increase in SVRI were observed in vasopressin group. The pressor effect of epinephrine in the vascular system was abrupt and only lasted a short period of time (within 5 min), while that of vasopressin was steady and lasted for more than 1 hr, especially regard to in DAP. When compared with epinephrine, vasopressin can be a more effective and safer choice in patients with severe hemorrhagic shock.

The prevalence, virulence potential, and antibiotic resistance of ophthalmic Staphylococcus pseudintermedius (SP) isolated from dogs were examined. Sixty-seven Staphylococcus species were isolated from ophthalmic samples and surveyed for species-specific sequences in the Staphylococcus intermedius group (SIG) nuclease gene (SInuc), exfoliative toxin gene for SIG (siet), and antibiotic resistance genes (blaZ and mecA). PCR-restriction fragment length polymorphism analysis of the pta gene was also performed. Fifty isolates were identified as SIG strains, all of which were found to be SP. The blaZ gene was detected in 42 of the 50 SP strains and mecA gene was observed in 18 of the 50 SP strains. The 50 SP strains were most susceptible to amoxicillin/clavulanic acid (94%) and chlorampenicol (70%), and highly resistant to tetracycline (94%) and penicillin (92%). It was also found that 16 (88.9%) mecA-positive SP strains were resistant to oxacillin, tetracycline and penicillin. All mecA-positive SP were resistant to more than four of the eight tested antibiotics and therefore considered SP with multi-drug resistance (MDR). Our results indicate a high prevalence of antibiotic resistance genes in ophthalmic SP along with a close relationship between MDR SP strains and the mecA gene. Based on our findings, judicious administration of antibiotics to companion dogs is necessary.

Three small breed dogs were referred for the evaluation of neurologic deficits. Upon physical and neurologic examination, all dogs displayed hyperesthesia, pain, and neck stiffness. Magnetic resonance imaging was performed on the brain and spinal cord, and all three dogs presented Chiari- like malformations and syringomyelia. These dogs were treated with prednisolone and furosemide, and showed rapid improvement of clinical signs. Chiari malformations and syringomyelia were not improved because of congenital disorders. This case report demonstrates the clinical and diagnostic features of Chiari-like malformations and syringomyelia in three small breed dogs.