To date, several DNA viral infections have been reported in psittacine birds. Psittacine beak and feather disease (PBFD) is characterized by symmetric feather dystrophy and loss and development of beak deformities. PBFD is caused by beak and feather virus, which belongs to the Circoviridae, and is the most important infection in psittacine birds worldwide. Avian polyomavirus infection causes acute death, abdominal distention, and feather abnormalities. Pacheco's disease (PD), which is caused by psittacid herpesvirus type 1, is an acute lethal disease without a prodrome. Psittacine adenovirus infections are described as having a clinical progression similar to PD. The clinical changes in psittacine poxvirus-infected birds include serious ocular discharge, rhinitis, and conjunctivitis, followed by the appearance of ulcerations on the medial canthi of the eyes. Internal papillomatosis of parrots (IPP) is a tumor disease characterized by progressive development of papillomas in the oral and cloacal mucosa. IPP has been suggested to caused by papillomavirus or herpesvirus. However, information about these diseases is limited. Here we review the etiology, clinical features, pathology, epidemiology, and diagnosis of these DNA viruses.

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Surfaces of the most luminal positions of mucosae are fundamental settlement sites of indigenous bacteria throughout the rat alimentary tract. In these positions, also epithelial cell-shedding sites, the special sugar expression in the glycocalyx is very important as it provides possible ligands of bacterial lectins for attachment to epithelial cells. Therefore, the sugar expression in glycocalyx of epithelial cells was lectin-histochemically surveyed using 21 lectins throughout the rat alimentary tract. From the tongue to the nonglandular part of the stomach, α-D-Man, α-D-Glc and α-D-GalNAc were detected on the surface of the keratinized stratified squamous epithelium. In the glandular part of the stomach, α-D-Man, β-D-Gal-4GlcNAc, D-Gal, D-GalNAc, D-GlcNAc, α-L-Fuc- α-D-Gal-β(1-4)GlcNAc and bisected triantennary N-glycans were detected on the surface of gastric superficial epithelial cells. From the duodenum to the ileum, (GlcNAc)_2-4 was expressed exclusively on the epithelial cells in the apical portions of the intestinal villi. From the cecum to the rectum, α-D-Man, β-D-Gal-4GlcNAc, D-Gal, D-GalNAc, α-D-Gal(1-3)D-GalNAc, (GalNAc)_n and NeuNAc were expressed on the intestinal superficial epithelial cells. These results suggest that special sugars are expressed on the most luminal portions of mucosae as exclusive epithelial cell-shedding sites, and that sugar expression differs among the various segments of the alimentary tract. These site differences might reflect differences in resident bacterial species in the rat alimentary tract.

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In this study, the microstructure of the cornea was compared among chickens (Gallus gallus), jungle crows (Corvus macrorhynchos), rats (Rattus norvegicus) and rabbits (Oryctolagus cuniculus). The density of keratocytes in the mammals was over 3 times that in the birds. The size of the keratocytes in the birds and rat were significantly lower than those in the rabbit. Using scanning and transmission electron microscopy, the bundles of collagen fibers in the birds were found to be well arranged, while those in the mammals were arranged randomly. The collagen lamellae of the birds were significantly thicker than those of the mammals, and the numbers of collagen lamellae in the birds were significantly smaller than in the mammals. The center-to-center distances between the collagen fibrils of the chicken and rabbit were significantly larger than those of the crow and rat. The densities of collagen fibrils in the chicken and rabbit were significantly less than those of the crow and rat.

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Cyclooxygenase (COX) generates free radicals and it is important in inflammatory response. In this study, we observed the immunoreactivity in mice (ICR and C57BL/6 strain), rats and gerbils. In these animals, COX-2 immunoreactivity was mainly detected in pyramidal cells of the hippocampal CA2/3 region and in granule cells of the dentate gyrus. COX-2 immunoreactivity in the CA2/3 region was the highest in ICR mice, while in gerbils COX-2 immunoreactivity was the lowest; COX-2 immunoreactivity in the dentate gyrus was the highest in rats and the lowest in gerbils. The protein levels of COX-2 were similar to the immunohistochemical data. COX-2 mRNA transcript was the highest in the gerbil and the lowest in the rat. In brief, COX-2 protein, not mRNA, in the hippocampus is generally higher in mice (ICR and C57BL/6 strain) than rats and gerbils.

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During pregnancy, the mammary epithelium and its supporting vasculature undergo extensive growth and proliferation in preparation for lactation, which is thought to be dependent on vascular endothelial growth factor (VEGF). We investigated the expression of VEGF, using immunohistochemistry and immunoblotting, in the mouse mammary gland during the reproductive cycle. Immunohistochemical studies localized VEGF protein predominantly in the cytoplasm of the mammary epithelium and revealed it to be strongly expressed in late pregnancy and early lactation. In addition, immunoblot analysis revealed a 45-kD VEGF band, corresponding to the homodimer of the VEGF-A₁₆₄ isoform, with increased expression towards the end of pregnancy but no additional increase with the onset of lactation. As the post-lactation period advanced, a dramatic decrease in VEGF was observed in the regressed mammary epithelium. The expression of VEGF suggests that mammary epithelium-derived VEGF may be involved in pregnancy-associated mammary growth and differentiation and angiogenesis, and regulate vascular permeability during lactation in an autocrine or paracrine manner.

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Clostridium botulinum produces a large toxin complex (L-TC) composed of neurotoxin (BoNT) and non-toxic proteins. In animal botulism, BoNT or L-TC is absorbed via the intestinal epithelium. To establish the cellular mechanisms of botulinum toxin absorption, we used cultured rat intestinal epithelial cells to test the binding and transport of serotype C1 BoNT and L-TC through the cell layers. BoNT and L-TC bound to and passed through the cell layers, with L-TC exhibiting larger binding and transport. Binding and transport of these toxins were inhibited by N-acetyl neuraminic acid or neuraminidase treatment of the cells. These results suggest that binding of serotype C1 BoNT and L-TC to sialic acid on the cells promoted their transport through intestinal epithelial cell layers.

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It has been reported that type I interferons (IFN-α/β) play an important role in innate immune responses against viral and bacterial infections. In this study, we used and examined naturally occurred canine periodontal disease to show the therapeutic efficacy of low dose oral administration (LDOA) of canine IFN-α subtype 4 (CaIFN-α4). We administered purified recombinant CaIFN-α4 expressed in a baculovirus system to dogs with or without gingival inflammation. We found that LDOA of CaIFN-α4 reduce periodontopathic bactrerial counts. LDOA induced improvement of naturally occurring gingival inflammation, and reduction of the stress marker responses was also observed after LDOA. These results suggest that LDOA of CaIFN-α4 has effectiveness for improvement of naturally occurring gingival inflammation in dogs.

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Maesil (Prunus mume) has long been used as a traditional drug and healthy food in East Asian countries. It possesses a number of beneficial biological activities including potential antimicrobial effects against pathogens. Probiotics also have antibacterial effects. Moreover, some probiotics have an important role in regulating the immune system. The present study evaluated the immune enhancing effects of fermented Msesil with probiotics (Saccharomyces cerevisiae, Bacillus subtilis and Lactobacillus acidophilus) in mice, especially against Bordetella bronchiseptica, as an initial step towards the development of feed supplements for the promotion of immune activity and prevention of disease, especially in pigs. Continuous ingestion of fermented Masesil with probiotics markedly increased the macrophage ratio in peripheral blood and the T lymphocyte ratio in the spleen. In addition, antibody production against formalin-killed B. bronchiseptica significantly increased in the mice fed fermented Maesil compared with the control group. The number of leukocytes was significantly higher in the bronchio-alveolar lavage obtained from the fermented Maesil-fed animals compared to it in the control group at day 3 (maximal peak time) after experimental B. bronchiseptica infection. Moreover, at 7 day post-infection, relative messenger RNA expression levels of tumor necrosis factor- α and interferon-γ were significantly increased in splenocytes of mice fed fermented Maesil compared with those in the control group. Taken together, these findings suggest that feed containing fermented Maesil with probiotics enhances immune activity in mice, especially against B. bronchiseptica, via the potent stimulation of non-specific immune responses.

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In this study, based on the data from FIV screening surveys of captive cats conducted by the Kyushu Veterinary Union and collaborators as part of the infection control program for Tsushima leopard cats (Prionailurus bengalensis euptilurus), we elucidated the spatial distribution of FIV-positive individuals among leopard cats and domestic cats using a geographic information system. Data from FIV screening surveys carried out among 86 leopard cats (1996-2006) and 713 captive domestic cats (2001-2006) were used for analysis. The analysis results were then spatially layered with the population density of leopard cats and that of captive domestic cats estimated from the number of households and used for assessment of FIV infection risk in each area. The prevalence rates of FIV were 3% (3/86) in leopard cats in Kami-shima, 13.6% (38/280) in domestic cats in Kami-shima and 10.6% (46/433) in domestic cats in Shimo-shima. The distribution of FIV on Tsushima Island was not uniform; on Kami-shima Island, FIV-positive domestic cats were concentrated in particular areas. We also performed risk analysis based on the population density of leopard cats, the prevalence rate of FIV among domestic cats in each area and the estimated population density of captive domestic cats and identified high FIV infection risk areas. All FIV-positive leopard cats were found in the identified high FIV infection risk areas.

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Chronic kidney disease is one of the most common disorders in dogs and cats. The plasma urea nitrogen (P-UN) and creatinine (P-Cre) concentrations are not sufficiently sensitive for early diagnosis of renal dysfunction. Although urine and plasma clearance methods allow earlier detection of reductions in the GFR, it is difficult to estimate a mildly reduced GFR from the values obtained by these methods, as they are also affected by physiological factors, such as body weight (BW) and age. The present study is a retrospective survey designed to assess the factors that affect markers of kidney function and to revaluate the clinical utility of the markers, including P-UN, P-Cre and GFR determined by plasma iohexol clearance (PCio) in dogs and cats. The P-UN, P-Cre and PCio values in dogs and the P-Cre and PCio values in cats were significantly correlated with BW (P<0.001). PCio in smaller dogs (≤ 15.0 kg) was significantly and inversely correlated with age. In smaller dogs, increase of P-UN alone might warrant a suspicion of a decreased GFR, but in contrast, P-Cre may be inefficient for detecting renal dysfunction or determining the severity of CKD compared with that in larger dogs (≥ 15.1 kg). P-Cre in larger dogs correlated better with PCio than in smaller dogs, suggesting that P-Cre in larger dogs was a more sensitive marker of reduced GFR.

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Expression levels of ABCB1, ABCC1, Lung resistance-associated protein (LRP), ABCG2, p53, p21^waf1, Bcl-2, CD40L, glutathione S-transferase alpha (GSTα), and O⁶-methylguanine-DNA-methyltransferase (MGMT) genes, and mutation of p53 gene were examined in 23 dogs with multicentric high-grade lymphoma to explore their association with drug resistance of the tumor cells. Dogs were divided into chemotherapy-sensitive (n=13) and -resistant (n=10) groups according to the response to a 6-month modified version of the University of Wisconsin (UW)-Madison chemotherapy protocol (UW-25), and expression levels of these factors and frequency of p53 gene mutation were compared between groups. No significant differences were observed in expression levels of each factor between groups. However, 4 dogs in the chemotherapy-resistant group showed high expression of ABCB1. No significant difference was observed in the frequency of p53 mutation between groups. A possible association of ABCB1 with resistance to UW-25 was shown, but no uniform mechanism associated with drug resistance could be identified in dogs with lymphoma.

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In order to determine the clinical conditions of Japanese Black (JB) cattle with growth retardation, we determined the changes of body growth, blood profiles of metabolism and hormones caused by intensified nutrition (sufficient total digestible nutrients and digestible crude protein for a target daily gain set at 1.2-1.3 kg/day) in three cattle. The daily gain (DG) was increased during the intensified period (Intense) compared with the preparation period (Pre), but the DG in the Intense period was 36-66% of the target DG. Serum albumin, total cholesterol, insulin and IGF-1 increased during the Intense period compared with the Pre period. Serum GH showed high levels in the Pre period, whereas it showed lower levels in the Intense period. These results suggested that the present growth retarded cattle had abnormalities in their metabolic systems and lacked nutrient absorption.

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A 5-year old neutered male cat was admitted to our hospital in the early morning with sudden onset of bilateral hindlimbs paralysis. Conservative anticoagulant therapy using heparin, warfarin, and dipyridamole, and thrombolytic therapy with urokinase administered by intravenous infusion were started. However, no improvement was noted even after 2 days of treatment, and the cat was started on local intra-arterial administration of urokinase via a catheter on disease day 3. Successful thrombolysis could be accomplished by this approach, and the motor function of both hindlimbs recovered on disease day 5. The cat could be discharged on disease day 9. Complications such as hemorrhage and hyperkalemia were not observed during the thrombolytic therapy. These results suggest that local intra-arterial administration of urokinase may be an effective approach for the treatment of FATE.

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The effect of a breath-hold on blood gas was evaluated in captive Pacific white-sided dolphins (Lagenorhynchus obliquidens). Serial blood collections were performed from a vessel on the ventral surface of the flukes during breath-hold. In total, 178 blood samples were taken from three dolphins for five trials in each animal. During a breath-hold, partial pressure of oxygen (Po₂) decreased from 152.5 to 21.8 mmHg and partial pressure of carbon dioxide (Po₂) conversely increased from 31.8 to 83.6 mmHg. The range of pH was 7.54 to 7.25, suggesting drastic change from alkalemia to acidemia. These wide ranges of blood gas imply a considerable change of oxygen affinity caused by the Bohr effect during breath-hold, which enable effective uptake and distribution of oxygen to metabolizing tissues.

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The ICR-derived glomerulonephritis (ICGN) mouse, an inbred strain with a hereditary nephrotic syndrome, is considered a good animal model of human idiopathic nephrotic syndrome. ICGN mice show proteinuria at a young age, developing hypoalbuminemia, hyperlipidemia, anemia and edema later on. However, their behavior associated with pruritus due to renal dysfunction has not been sufficiently investigated. In the present study, we examined whether ICGN mice exhibit the scratching behavior reflecting pruritus. Mice aged 21 or 27 weeks were found to scratch persistently or intermittently, particularly those with scars. Furthermore, the scratching may have reflected a pruritus associated with renal dysfunction because it was inhibited by an opioid antagonist, naltrexone (3 mg/kg), effective against pruritus in hemodialysis patients. The results suggest that the ICGN mouse is a useful model with which to examine pruritus due to renal dysfunction.

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Hepatocellular carcinoma with metastases to lymph nodes and adrenal glands was found in a 26-year-old male Hokkaido brown bear (Ursus arctos yesoensis). Left hepatic lobe was largely replaced by well-differentiated neoplastic cells, whereas poorly differentiated tumor cells had proliferated in part of the left hepatic lobe, in scattered nodules in the remainig liver tissue, and at the metastatic sites. Immunoreactivity for hepatocyte antigen (hepatocyte paraffin 1 antibody) and alpha-fetoprotein was observed in both well- and poorly differentiated neoplastic cells in the liver and metastatic foci. To our knowledge, this case is the first report of hepatocellular carcinoma in brown bears.

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The aim of this study was to develop in situ hybridization for detection of Mycoplasma hyorhinis in formalin-fixed, paraffin-wax-embedded tissues from pigs with polyserositis. M. hyorhinis was isolated from the spleen (2 pigs) and pericardium (1 pig). M. hyorhinis DNA was detected 16 out of 20 pigs with polyserositis. In situ hybridization produced a distinct positive signal for the M. hyorhinis p37 gene in inflammatory cells in the polyserositis. In situ hybridization developed in the present study present diagnostic tools capable of detection of M. hyorhinis in formalin-fixed, paraffin-wax-embedded tissues from the naturally infected pigs.

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A dead whooper swan was found in an area of cropland near a stream and was submitted to the National Veterinary Research and Quarantine Service (NVRQS) in Korea. The affected animal was in relatively good condition. Grossly, the heart was enlarged and had pale and dark red stripes. A white, elongate parasite was seen on the cut surface of the heart. Histopathologically, severe lymphohistiocytic inflammation, myocardial necrosis, many adult heart worms and microfilariae were observed in the myocardium. Hemorrhage, lymphocytic inflammation, mineralization, and myocardial degeneration were also seen around the adult worms. No bacteria or viruses were isolated from the affected bird. The pathological findings indicate that the whooper swan was infected with nematodes, presumably Sarconema eurycerca, resulting in non-suppurative myocarditis.

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The objective of the present study was to determine whether corticotropin-releasing hormone (CRH) influences porcine corpus luteum function. The gene expressions of CRH receptors (CRH-R) were determined in the CLs of Chinese Meishan pigs during the estrous cycle. The effects of CRH on progesterone (P), estradiol-17β (E) and prostaglandin (PG) F_2α secretion by cultured luteal cells were also investigated. Messenger RNAs of the CRH-R were clearly expressed in the CL throughout the estrous cycle, and the mRNA level was higher at the regressed stage than at the other stages (P<0.05). When the cultured luteal cells obtained from the mid-luteal stage CL (days 8-11) were exposed to CRH (50-5000 ng/ml), P secretion by the cells was significantly reduced at the highest dose (P<0.05), whereas CRH had no effect on E and PGF_2α secretion by the cells. The overall results suggest that CRH inhibits local P production from luteal cells via its specific CRH-R, implying that CRH plays some roles in regulating porcine CL function during the estrous cycle, especially in the period of luteolysis.

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To evaluate the effects of IV fentanyl administration on the end-tidal sevoflurane concentration (ET_SEVO) in thoroughbred racehorses, the ET_SEVO required for internal fixation of longitudinal fractures was compared between horses anesthetized with sevoflurane-fentanyl (Group SF; n=9) and those anesthetized with sevoflurane alone (Group S; n=9). The loading dose of fentanyl (5.0 μg/kg) was administered over 15 min followed by a maintenance dose of fentanyl (0.1 μg/kg/min) throughout the operation in Group SF. The mean ET_SEVO during the operation in Group SF (2.6 ± 0.2%) was significantly lower than in Group S (3.0 ± 0.3%). The plasma fentanyl concentrations (6.12 ± 0.88 to 7.78 ± 1.12 ng/ml) in 7 out of 9 horses in Group SF were stable and did not change significantly throughout the operation. The mean dobutamine infusion rate required for maintaining a mean arterial blood pressure between 60 and 80 mmHg during the operation in Group SF (0.56 ± 0.30 μg/kg/min) was significantly lower than in Group S (0.90 ± 0.16 μg/kg/min). The qualities of the recoveries were clinically acceptable, and serious complications were not observed in either group. In conclusion, continuous IV fentanyl administration reduced the sevoflurane requirement by 13% in thoroughbred racehorses undergoing orthopedic surgery; however, fentanyl was considered to be less effective in horses compared with other species.

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A 5-year-old castrated male ferret was referred for hind limb paresis and subcutaneous mass at the lumber area. Based on clinical examination including computed tomography, extension of the mass to the abdominal cavity was confirmed. An exploratory laparotomy revealed that the mass at the cranial area of the left kidney extended dorsally to the vertebra and to the subcutis. The excised mass was histologically diagnosed as a medullary tumor of the adrenal gland, and some neoplastic cells were beta III-tubulin-, doublecortin- and neurofilament-positive. Based on these findings, the tumor was considered to be a neuroblastoma.

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As part of an ongoing effort to understand the biological response of wild and domestic ungulates to different environmental pollutants such as dioxin-like compounds, cDNAs encoding for CYP1A1 and CYP1A2 were cloned and characterized. Four novel CYP1A cDNA fragments from the livers of four wild ungulates (elephant, hippopotamus, tapir and deer) were identified. Three fragments from hippopotamus, tapir and deer were classified as CYP1A2, and the other fragment from elephant was designated as CYP1A1/2. The deduced amino acid sequences of these fragment CYP1As showed identities ranging from 76 to 97% with other animal CYP1As. The phylogenetic analysis of these fragments showed that both elephant and hippopotamus CYP1As made separate branches, while tapir and deer CYP1As were located beside that of horse and cattle respectively in the phylogenetic tree. Analysis of dN/dS ratio among the identified CYP1As indicated that odd toed ungulate CYP1A2s were exposed to different selection pressure.

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The vhs (virion host shutoff) is highly conserved in alphaherpesvirus, including pseudorabies virus (PRV). In an attempt to explore the function of vhs of PRV, we constructed and characterized a mutant virus (Δ41). In the absence of vhs activity, Δ41 mutant is highly attenuated in mice model and the lethality is correlated with the virus dissemination in neural tissues. As with herpes simplex virus type 1 (HSV-1), the prototype virus of alphaherpesvirus, the pronounced decrease in cellular protein synthesis triggered by wild type PRV was largely restored in cells infected with Δ41 virus. Furthermore, tumor necrosis factor-α (TNF-α) protein expression was elevated significantly in spleen of mice infected with vhs mutant virus. Since TNF-α has been indicated to be an important cytokine in the innate immune response against various infections, our results implicate vhs may contribute to the protection against PRV lethality via the action of TNF-α. Overall, we confirm the shutoff function of vhs protein in PRV, and demonstrate the role that vhs protein plays in virulence, and regulation of cytokine production.

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Although vaccination against feline calicivirus (FCV) infection is widespread in Japan, FCV-associated diseases are still a significant problem in cats. Thus, we developed a new trivalent inactivated vaccine, Kyoto Biken Feline-CPR, consisting of three FCV strains; one was the production strain of our previous vaccine, and the others were screened from 60 field isolates obtained between 1998 and 2000 based on cross-neutralization tests. In this report, the three FCV strains used for development of the new vaccine were antigenically and genetically characterized. The three strains were antigenically quite different, as revealed by cross-neutralization tests. Alignment of deduced amino acid sequences of capsid regions A to E revealed that there were marked differences between the strains in both the N- and C ends of region E. Antisera against the three vaccine strains, our new vaccine and 2 commercial vaccines were then evaluated for neutralization with 58 field isolates collected between 2003 and 2006. Rat antisera against the three vaccine strains and a mixture of the 3 strains neutralized 49, 37, 42 and 55 isolates, respectively. Cat antiserum against the new vaccine neutralized 50 (86.2%) isolates, whereas the numbers neutralized by cat antisera against 2 commercial vaccines were 37 (63.8%) and 25 (43.1%). In conclusion, the immunological and genetic properties of the 3 vaccine strains investigated varied widely, and the Kyoto Biken Feline-CPR vaccine may have more potential to meet the antigenic diversity of FCVs spreading throughout Japan.

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The relationship between canine respiratory coronavirus (CRCoV) and canine influenza virus (CIV) seropositivity in dogs in Korea was examined. Sixty-two of the 483 samples (12.8%) were seropositive for CRCoV by indirect fluorescent antibody (IFA) analysis. Nineteen animals were seropositive for CIV by ELISA out of the 385 samples tested. Serum antibodies for both viruses were detected in 6 of the 483 dogs sampled, suggesting that these viruses are present in dogs in Korea. Although the role of CRCoV in canine infectious tracheobronchitis has not been fully elucidated, co-infection with CIV may synergistically worsen respiratory clinical signs and result in more severe canine tracheobronchitis.

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We evaluated antigen detection kits for human rotavirus with regard to their usefulness for diagnosing equine rotavirus infection. Limiting dilution analyses showed that of the seven kits investigated the Dipstick `Eiken' Rota (Dipstick) had the highest sensitivity to two serotypes of equine rotavirus. The Dipstick did not cross-react with several equine intestinal pathogens. An investigation using 249 fecal samples indicated that the sensitivity of the Dipstick was 81.9% and 47.3%, and its specificity was 98.2% and 99.0%, and its concordance rate was 92.8% and 68.3%, compared with values obtained using reverse transcription polymerase chain reaction and reverse transcription loop-mediated isothermal amplification, respectively. Although a negative result does not preclude the possibility of equine rotavirus infection, the Dipstick would be useful as routine test for diagnosing equine rotavirus infection in daily clinical practice because of its ease of handling.

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