The aim of this study was to verify the accuracy of echocardiography by dual-source computed tomography (DSCT). Seven normal beagles underwent DSCT and echocardiography. Echocardiographic measurements were obtained according to the American Society of Echocardiography guidelines. The DSCT images were reconstructed onto the same echocardiographic image plane by using a reconstruction program, and then anatomical measurements were obtained. Nonparametric analysis was used for verifying the significance of each of the measured parameters. The anatomical measurements obtained using echocardiography and DSCT were not significant (P>0.05), and the difference between the measurements obtained using both the methods were within 95% confidence intervals except those for interventricular septal thickness and left ventricular posterior wall thickness in end diastole. The reasons for these differences were considered to be the adjacent structures such as papillary muscles or chordae tendineae that may have influenced the echocardiographic findings, lower far-field image quality of echocardiography, low test-retest reproducibility of echocardiography, high-quality images of DSCT minimizing the motion artifact and the retrospective ECG gating technique of DSCT that offered an adequate timing decision for the systolic and diastolic phase during cardiac movement. Although there were differences in the measurements of interventricular septal thickness and left ventricular posterior wall thickness in end diastole obtained using echocardiography and DSCT, we could conclude that echocardiographic measurement is as accurate and reliable as DSCT for cardiac anatomical assessment.

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We examined sexual dimorphism in the craniodental traits of the raccoon dog Nyctereutes procyonoides from South Korea. Univariate comparisons of skull (cranium and mandible) and dental measurements revealed a small extent of sexual dimorphism in some measurements. The most indicative dimorphic measurements were the breadths of the upper and lower canines which were around 8% larger in male specimens on average. On the other hand, multivariate analyses using only skull traits showed slightly a clearer separation between sexes than those using only dental ones. This discrepancy may be derived from a higher variability in dental traits than in those of the skull. In conclusion, sexual dimorphism within N. procyonoides of South Korea is present, but was not so pronounced as for other local populations. However, measurements showing significant sexual dimorphism varied between different localities. This suggests that the selective forces acting upon craniodental morphology of each sex vary between populations of the species.

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To differentiate the avirulent from virulent strains of avian paramyxovirus serotype-1 (APMV-1, Newcastle disease virus), PCR and restriction endonuclease analysis (REA) was employed. Primer sequences were used to amplify a 766-base pair fragment that included the fusion protein cleavage site. REA of PCR products generated by Hin1 I and Apa I enabled the differentiation of avirulent field and vaccine strains from more virulent field strains of APMV-1 in Japan.

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As study of multidrug efflux pumps is a crucial step for development of efflux pump inhibitors for treatment of Pseudomonas aeruginosa infection, the objective of this study was to examine the contribution of the MexXY multidrug efflux systems and other chromosomal mechanisms in aminoglycoside (AMG) resistance in P. aeruginosa isolated from dogs and cats. Thirteen Pseudomonas aeruginosa isolates from canine and feline infections were examined for contribution of the MexXY multidrug efflux pump and four other chromosomally-encoded genes including PA5471, galU, nuoG and rplY to AMG resistance. All the isolates were resistant to multiple AMGs and expressed mexXY. Deletion of mexXY caused 2- to 16-fold reduction in AMG MICs. Overproduction of MexXY did not fully account for the observed AMG resistance. No good correlations were detected between MexXY transcription level and AMG MICs. While no mutations were found in mexZ, PA5471 expression varied and its impact on MexXY expression and AMG resistance is diverse. No mutations were found in galU. Only two isolates carried a single base change G-367-T in rplY. Complete transcription of nuoG was detected in all the isolates. In conclusion, the MexXY multidrug efflux pump plays a role in AMG resistance in the dog and cat P. aeruginosa isolates, while disruption of nuoG, rplY and galU did not have a significant impact. These results indicate the existence of uncharacterized AMG-resistance mechanisms.

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The present study was carried out to assess the frequency of methicillin-resistant staphylococci (MRS) among racehorses (n=209) and veterinary personnel (n=13) as well as environmental surfaces (n=14) at an equine hospital in Adana, Turkey. In addition, species distribution, antimicrobial susceptibility, resistance genes, staphylococcal chromosomal cassette mec (SCCmec) type and clonality of these isolates were also investigated. MRS were identified by 16S rRNA sequencing, and typed by pulsed-field gel electrophoresis (PFGE). As a result, MRS was isolated in horses (48.3%), clinic staff (92.3%) and environmental samples (71.4%). Of the 123 MRS isolates, 118 isolates were identified as Staphylococcus lentus, and the remaining ones were found to be S. sciuri (n=3), S. intermedius (n=1) and S. fleuretti (n=1). All isolates were found to be susceptible against vancomycin, quinupristin-dalfopristin and rifampicin. Additionally, single or various combinations of resistance genes were detected among MRS isolates. SCCmec type II was identified in all isolates. Similar PFGE patterns were observed among MRS isolated from horses, humans, and environmental samples. Since MRS were concurrently isolated from horses and humans it is suggested that cross-transmission of MRS between horses and humans might occur. However, it cannot be ruled out that transmission is human to animal or animal to human.

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Streptococcus suis is an important pathogen for both swine and humans. In this study, we genotyped 105 S. suis isolates from porcine endocarditis in East Japan on the basis of profiles of capsular serotype-specific, virulence-associated and pilus-associated genes. The most common genotype was cps2J/mrp+/epf-/sly-/sbp2-/sep1-/sgp1+ (76.19%), followed by nt(non-typeable)/mrp+/epf-/sly-/sbp2-/sep1-/sgp1+ (7.62%) and cps2J/mrp+/epf+/sly+/sbp2+/sep1-/sgp1- (7.62%). The representative isolates of mrp+/epf-/sly-/sbp2-/sep1-/sgp1+ were classified into ST28 complex, a clonal complex previously referred to as ST27 complex, whereas those of mrp+/epf+/sly+/sbp2+/sep1-/sgp1- were classified into ST1 complex by multilocus sequence typing. Because the majority of human clinical isolates were assigned to ST1 and ST28 complexes, most isolates from porcine endocarditis investigated in this study may have the potential to cause S. suis infection in humans.

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Melamine toxicity is recognized as a distinct form of renal failure due to occlusion of the renal tubules by the compound melamine and its deaminated derivative, cyanuric acid. The morphology of melamine-cyanurate crystals in vivo differs from that in vitro, being rounded in the former case but needle-like in the latter. The reasons for this difference in morphology between in vivo and in vitro crystals remain unknown. In the present study, we investigated the in vitro effects of several possible intra-renal factors, i.e., pH and serum and urinary proteins, on the morphology of melamine-cyanurate crystals in order to clarify what might be responsible for the formation of rounded urolites in vivo. We found that serum proteins, such as fetal bovine serum, bovine serum albumin and bovine gamma-globulin, can alter the morphology of melamine cyanurate, turning it into rounded crystals. The urinary protein beta-2-microglobulin had a less pronounced effect. The crystal morphology was unaffected by pH. Based on the present in vitro findings and known clinical data, we suggest a putative protein-related model for melamine-cyanurate formation in the kidney.

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A swine-specific CpG motif enriched plasmid (pUC18-CpG) was constructed in this study. Its immunostimulant property was tested in vitro via lymphocyte transformation assay using swine peripheral blood mononuclear cells (PBMCs). The recombinant plasmid showed higher Stimulation Index (SI) compared to the positive control (LPS). In a following animal experiment, pUC18-CpG was co-administered with a commercial swine FMD killed vaccine. Animals in the pUC18-CpG adjuvanted groups showed much higher antibody titers during the vaccination period.

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It has been considered that drinking oxygenated water improves oxygen availability, which may increase vitality and improve immune functions. The present study evaluated the effects of oxygenated drinking water on immune function in pigs. Continuous drinking of oxygenated water markedly increased peripheral blood mononuclear cell proliferation, interleukin-1β expression level and the CD4⁺:CD8⁺ cell ratio in pigs. During Salmonella Typhimurium infection, total leukocytes and relative cytokines expression levels were significantly increased in pigs consuming oxygenated water compared with pigs consuming tap water. These findings suggest that oxygenated drinking water enhances immune activity in pigs and increases immune responses of pigs during S. Typhimurium Infection.

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An epidemiological survey of Iriomote cats (Prionailurus bengalensis iriomotensis) was conducted to understand the prevalence and molecular characteristics of hemotropic mycoplasma (hemoplasma). A series of ecological surveys of Iriomote cats were performed between November 2003 and September 2010. During this period, 31 Iriomote cats were captured or found, and 39 blood samples were collected. Polymerase chain reaction screening for hemoplasmas and BLAST searches revealed that 4 of the 31 cats were positive for hemoplasma infection (n=3, Mycoplasma haemofelis [Mhf]; n=1, ‘Candidatus M. turicensis’ [CMt]). The 4 infected cats were captured or found in the northern area of the island of Iriomote. Phylogenetic analyses revealed close relationships between Mhf and CMt isolated from Iriomote cats compared with those from domestic cats and other wild felids. In our study, we identified two species of hemoplasma in Iriomote cats. The number and location of the hemoplasma-positive cats appeared to be limited; however, continuous surveillance of hemoplasma infection in Iriomote cats is necessary.

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The BioMasher is a disposable homogenizer that was developed to homogenize bovine brain tissue for bovine spongiform encephalopathy diagnosis. Capable of preventing the biohazard risk from infectious samples, it also prevents cross-contamination among samples. The BioMasher is thus widely used in biochemical research, especially for RNA extraction. Here, we tested a novel BioMasher application for RNA extraction from animal and plant tissues. We also developed a grinding machine specific for the BioMasher, named the BioMasher Power-Plus. We developed RNA extraction protocols using the BioMasher combined with the BioMasher Power-Plus. We compared RNA extraction efficiency of the BioMasher with that of the FastPrep and the glass homogenizer. Though the RNA extraction efficiency by the BioMasher was nearly equivalent to that of the FastPrep and the glass homogenizer, sample preparation time was shorter for the BioMasher. The utility of RNA extraction by the BioMasher was examined in mouse, rat, and tomato tissue samples. In the rodent tissues, the highest extraction efficiency of total RNA was from liver, with lowest efficiency from fibrous tissues such as muscle. The quality of extracted total RNA was confirmed by agarose gel electrophoresis which produced highly visible clear bands of 18S and 28S rRNAs. Reproducibility among different operators in RNA extraction from tomato roots was improved by using the BioMasher Power-Plus. The BioMasher and BioMasher Power-Plus provide an effective and easy homogenization method for total RNA extraction from some rodent and plant tissues.

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Female reproductive organs show organ-specific morphological changes during estrous cycles. Perinatal exposure to natural and synthetic estrogens including diethylstilbestrol (DES) or estrogenic chemicals induces estrogen-independent persistent proliferation of vaginal epithelium in mice. To understand the underlying mechanism of the estrogen-independent persistent vaginal changes induced by perinatal DES exposure, we examined global gene expressions in the vaginae of ovariectomized adult mice exposed neonatally to DES using a microarray. The cell cycle-related gene, p21, a cyclin-dependent kinase inhibitor, showed upregulation in the vagina, and p21 protein was localized in the basal layer of the vaginal epithelium in mice exposed neonatally to DES and an estrogen receptor α agonist, propyl pyrazole triol (PPT). The expressions of Notch receptors and Notch ligands were unchanged; however, the mRNAs of hairy-related basic helix-loop-helix (bHLH) transcription factor genes, Hes1, Hey1 and Heyl were persistently downregulated in the vagina, indicating estrogen-independent epithelial cell proliferation in mice exposed neonatally to DES and PPT.

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Spontaneously Diabetic Torii (SDT) rat is a hereditary model of diabetes. Although the SDT rat shows severe diabetic complications, the onset of hyperglycemia is late. SDT fatty rat, established by introducing the fa allele of the Zucker fatty rat to SDT rat, develops diabetes much faster than SDT rat. In the present study, diabetic peripheral neuropathy (DPN) was evaluated to show the further usefulness of this animal model. Motor nerve conduction velocity (MNCV) was delayed, and the number of sural nerve fibers was decreased in SDT fatty rat. Treatment of pioglitazone lowered blood glucose level and prevented delay of MNCV in SDT fatty rats. SDT fatty rat is a useful animal model for studies of DPN in type 2 diabetes.

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A 16-year-old male mixed-breed dog was euthanized due to progression of renal failure caused by renal adenocarcinoma in the left kidney. Apart from main symptomatic lesion, accumulation of transparent jelly-like fluid was observed between the right femoral muscles. Gross examination of the right hindlimb revealed multiple nodules in the articular surface and capsule of the stifle joints, which extended into the crural muscles. Histopathologically, the joint and intermuscular masses were characterized by variously-sized hypocellular nodules consisting of spindle to stellate cells suspended in an abundant myxoid matrix. There were cystic structures within the intermuscular masses, lined by synoviocyte-like cells. Based on the gross and histopathologic findings, the case was diagnosed as synovial myxoma with extensive intermuscular infiltration. Synovial myxoma should be considered in the differential diagnosis of dogs with myxomatous tumor between skeletal muscles, even in absence of joint or muscle symptoms.

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A case of mast cell sarcoma in a 5-month-old Holstein female calf is described. Macroscopically, enlargement of the spleen, lymph nodes, tonsils and kidneys was noted, and there were tumor masses in the neck region and on the pleura and peritoneum. The pericardium and uterine and ureter walls were also involved by tumor. Most neoplastic cells had eosinophilic granules, which were metachromatic and positive for naphthol AS-D chloroacetate esterase and tryptase, whereas smaller numbers of cells were positive for factor VIII-related antigen, a marker of megakaryocytes. Some of the predominant type of these tumor cells were found within the epithelia of the lungs, tonsils, gastrointestinal tract, liver, ureters, urinary bladder and uterus. Their normal counterparts were considered to be globule leukocytes.

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This study elucidated differences in predisposition to the gastrointestinal adverse effects of ketoprofen between young and adult cats. Ketoprofen was administered subcutaneously (2.0 mg/kg, s.c.) once a day for 3 days. The animals were sacrificed 24 hr after final injection to allow examination of gastrointestinal mucosal lesions. Ketoprofen caused gastric lesions in adult cats (>6 months) but not in young cats (<3 months). Ketoprofen caused more severe small intestinal lesions in adult cats than in young cats. In the study of prevention of lipopolysaccharide (LPS)-induced hyperthermia using ketoprofen, young and adult cats of both sexes were administered LPS (0.3 μg/kg, intravenously), and body temperature was measured 24 hr later. Ketoprofen was administered subcutaneously 30 min before LPS injection. LPS-induced hyperthermia was almost completely inhibited by pretreatment with ketoprofen in both adult and young cats. In the pharmacokinetics of ketoprofen, plasma concentrations were analyzed by high-performance liquid chromatography. No significant differences were observed in plasma concentrations of two mirror-image R(-) and S(+) ketoprofen between young and adult cats from 0.5–4 hr after injection. As observed in a previous study using flunixin, the degree of gastrointestinal damage was unrelated to plasma concentrations of ketoprofen. The results of this study demonstrated that ketoprofen is safer for use in young cats than in adult cats from the viewpoint of gastrointestinal adverse effects.

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It has been reported that green tea catechins enhance the force of contraction of isolated heart muscle preparations. However, it remains controversial whether or not the increase in force of contraction is related to an increase in the intracellular Ca²⁺ concentration ([Ca²⁺]i). In this study, the relationship was investigated using a left atrial muscle preparation isolated from guinea pig heart. In the left atrial muscle preparations without fura-2/AM loading, neither EGC (epigallocatechin) nor EC (epicatechin) influenced the force of contraction, but EGCG (epigallocatechin gallate) and ECG (epicatechin gallate) increased the force of contraction in a dose-dependent manner. The ED₅₀ value of EGCG was significantly higher than that of ECG. In the atrial muscle preparations loaded with fura-2/AM, EGCG and ECG increased the amplitude of [Ca²⁺]i(peak [Ca²⁺]i minus diastolic [Ca²⁺]i) which is associated with the increase in force of contraction. Simple regression analysis between the degree of increase in the force of contraction and the increase in the amplitude of [Ca²⁺]i revealed a positive correlation in EGCG, ECG and CaCl₂. In addition, the slopes of the regression lines of EGCG and ECG were comparable with those of CaCl₂. It was suggested that atrial muscle preparations had a higher affinity for ECG than EGCG, and that the increase in the force of contraction by EGCG and ECG was closely related to the increase in the amplitude of [Ca²⁺]i.

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The objective of this study was to compare the method of thermography by using three different resolution thermal cameras and basic software for thermographic images, separating the two persons taking the thermographic images (thermographers) from the three persons interpreting the thermographic images (interpreters). This was accomplished by studying the repeatability between thermographers and interpreters. Forty-nine client-owned dogs of 26 breeds were enrolled in the study. The thermal cameras used were of different resolutions-80 × 80, 180 × 180 and 320 × 240 pixels. Two trained thermographers took thermographic images of the hip area in all dogs using all three cameras. A total of six thermographic images per dog were taken. The thermographic images were analyzed using appropriate computer software, FLIR QuickReport 2.1. Three trained interpreters independently evaluated the mean temperatures of hip joint areas of the six thermographic images for each dog. The repeatability between thermographers was >0.975 with the two higher-resolution cameras and 0.927 with the lowest resolution camera. The repeatability between interpreters was >0.97 with each camera. Thus, the between-interpreter variation was small. The repeatability between thermographers and interpreters was considered high enough to encourage further studies with thermographic imaging in dogs.

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Anaplasma phagocytophilum causes human granulocytic anaplasmosis (HGA) and tick-borne fever in ruminants. A closely related and potentially novel Anaplasma sp. in Japan was recently characterized. The aims of the study were to provide molecular evidence for the presence of these 2 species in Japan, and to develop a reliable PCR method based on the nucleotide differences within the citrate synthase (gltA) gene. DNA samples from 182 ixodid ticks (134 Ixodes persulcatus, 35 Haemaphysalis douglasii and 13 I. ovatus) collected from 2 sites in Hokkaido, Japan, were screened for A. phagocytophilum and its closely related Anaplasma sp. (herein designated as Anaplasma sp. Japan) using 16S rRNA PCR, revealing a combined prevalence rate of 27.5% (50 samples). The positive samples were then used to evaluate a newly developed gltA-based nested PCR method. Selected positive samples were further characterized using the groEL gene for confirmation and phylogenetic analyses. Two groups of sequence results were obtained: those that had closer identities with (1) A. phagocytophilum (99.5–99.6% for 16S rRNA, 97.5% for gltA and 98.4% for groEL), and those that had closer identities with (2) Anaplasma sp. closely related to A. phagocytophilum in Japan (99.3% for 16S rRNA, 96.4–98.7% for gltA and 97.5–97.9% for groEL). The present study confirmed the distinct presence of A. phagocytophilum and its closely related Anaplasma sp. in Japan, and developed a new PCR detection method based on gltA that can distinguish the 2 organisms.

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To clarify the factors for occurrence of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli in broilers, two flocks (1 day of age) fed a diet with or without antibiotics were kept in a broiler house sanitized with disinfectants. ESBL-producing E. coli, however, was detected at a concentration of over 10⁶ CFU/g of feces at 9 days of age to 49 days of age in both broiler flocks. Therefore, this indicated that the antibiotics other than cephalosporins used in this study had no effect due to co-selection on the numbers of ESBL-producing E. coli in broiler feces during this period. When a flock was kept with diet containing antibiotics for 49 days in a laboratory animal room, no ESBL-producing E. coli was detected in the flock. These results suggest that the occurrence of ESBL-producing E. coli may not be related to feeding with antibiotics and that the contamination of broiler houses with ESBL-producing E. coli might be an important factor.

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Hepatitis E virus (HEV) infection has previously been reported in wild mongooses on Okinawa Island; to date however, only one HEV RNA sequence has been identified in a mongoose. Hence, this study was performed to detect HEV RNA in 209 wild mongooses on Okinawa Island. Six (2.9%) samples tested positive for HEV RNA. Phylogenetic analysis revealed that 6 HEV RNAs belonged to genotype 3 and were classified into groups A and B. In group B, mongoose-derived HEV sequences were very similar to mongoose HEV previously detected on Okinawa Island, as well as to those of a pig. This investigation emphasized the possibility that the mongoose is a reservoir animal for HEV on Okinawa Island.

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Soil samples from the ground surface and feces and blood from a mixed-breed male pig were collected on April 10, 2011 at a farm within 20 km of the Fukushima Daiichi nuclear power plant. The radioactivity of each sample was measured using a Ge semiconductor detector. Despite the fact that the pig had been fed non-contaminated imported feed, ¹³¹I, ¹³⁴Cs and ¹³⁷Cs were detected in the feces, and ¹³⁴Cs and ¹³⁷Cs were detected in the blood clots. Because it is considerably difficult to measure radioactive contamination in the edible muscle of living livestock, bioassays are an option for the screening of radioactive contamination in living livestock to ensure food safety.

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Previous animal studies have shown that transplantation of mesenchymal stem cells (MSCs) into spinal cord lesions enhances axonal regeneration and promotes functional recovery. We isolated the MSCs derived from fat, bone marrow, Wharton’s jelly and umbilical cord blood (UCB) positive for MSC markers and negative for hematopoietic cell markers. Their effects on the regeneration of injured canine spinal cords were compared. Spinal cord injury was induced by balloon catheter compression. Dogs with injured spinal cords were treated with only matrigel or matrigel mixed with each type of MSCs. Olby and modified Tarlov scores, immunohistochemistry, ELISA and Western blot analysis were used to evaluate the therapeutic effects. The different MSC groups showed significant improvements in locomotion at 8 weeks after transplantation (P<0.05). This recovery was accompanied by increased numbers of surviving neuron and neurofilament-positive fibers in the lesion site. Compared to the control, the lesion sizes were smaller, and fewer microglia and reactive astrocytes were found in the spinal cord epicenter of all MSC groups. Although there were no significant differences in functional recovery among the MSCs groups, UCB-derived MSCs (UCSCs) induced more nerve regeneration and anti-inflammation activity (P<0.05). Transplanted MSCs survived for 8 weeks and reduced IL-6 and COX-2 levels, which may have promoted neuronal regeneration in the spinal cord. Our data suggest that transplantation of MSCs promotes functional recovery after SCI. Furthermore, application of UCSCs led to more nerve regeneration, neuroprotection and less inflammation compared to other MSCs.

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We hypothesized that semi-quantitative determinations of changeable blood flows in granulation and scar tissues during tendon healing could be helpful for differentiation between the acute phase rich in blood vessels and the remodeling phase with fewer vessels. Ten Thoroughbreds with injured superficial digital flexor tendon (SDFT) in a forelimb were used for evaluation of blood flows in the injured tendons of racehorses using color Doppler (CD) ultrasonography. Using longitudinal CD images, features of maximum color activities were defined. These were rhythmically blinking, tiny to small signals (grade 1), pulsatile expanded dots (grade 2), and dynamic streams (grade 3). Grade of color activity in CD ultrasonography could be useful for quantitative assessment of equine SDFT repair.

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The aim of this study was to evaluate the relationships between carapace parameters as indicators of age and plasma elements in 25 captive hawksbill sea turtles. Particle-induced X-ray emission allowed detection of 23 trace and major elements. There were significant but weak correlations between the virtual carapace surface area and plasma bromide (r= -0.552, P<0.01), phosphorus (r=0.547, P<0.01), lead (r=-0.434, P<0.05) and strontium (r=0.599, P<0.01), while there were no significant correlations with other elements. These results suggest that major and trace plasma elements in captive sea turtles show almost no variation with carapace parameters, suggesting that the increase in plasma elements seen in wild sea turtles might be the result of marine pollution.

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A national serological survey of caprine arthritis-encephalitis virus (CAEV) infection was conducted using an enzyme-linked immunosorbent assay (ELISA) and an agar gel immunodiffusion (AGID) test. A total of 658 black goats of various breeds were sampled from 59 farms in three regions of Korea. The CAEV-positive goats were predominantly detected in the Southern region (n=17) as compared with the Northern (n=1) and Central regions (n=0) (χ²=6.26, P=0.044). Among 658 goats tested, 18 were positive in both ELISA and AGID, indicating a CAEV prevalence of 2.73% (95% confidence interval: 1.74–4.28). These results indicate that CAEV is present in Korean black goats.

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