Development of the external genitalia of fetal and neonatal cat were studied macroscopically, paying attention to the formation of the labia and the sexual differentiation. The female urogenital folds budded from each side of the genital tubercle and, gradually extended to the tip of the genital tubercle by the 6.8 cm stage in crown-rump length. Then, the well-developed urogenital folds ensheathed completely the genital tubercle to form the prepuce of clitoris and the labia, flanking the external opening of vagina as the folds of skin which were equivalent to the labia minora in humans. The genital swellings known to become the labia majora in humans were clearly recognized in the caudolateral region of the genital tubercle during the fetal stage. These swellings became flat and obscure after birth. Thus, in cats the genital swellings did not join to the formation of the labia in the same way as in humans. The sex difference in the external genitalia was first observed at the 3.2-3.3 cm stages. In the male, the anogenital raphe appeared and the caudal portion of the genital swellings moved and fused each other at the caudal region of the genital tubercle. In the female, both features were not easy to observe.

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The aim of this study was to determine whether the thickness of the adrenocortical zone is associated with age in virgin and parous female DDD mice. The zona reticularis and zona glomerulosa of parous mice tended to be thicker than those of virgin mice at all ages. The zona fasciculata lactating parous mice was significantly thicker than that of virgin mice at 20 weeks of age (P<0.01). Age did not affect the thickness of the three outer adrenocortical zones in either group. However, in virgin mice, the X zone consisted of vacuolated and nonvacuolated cells at 5 weeks of age and only of vacuolated cells at 10 weeks of age; the number of vacuolated cells and the thickness of the zone decreased at 40 weeks of age. In contrast, parous mice of all ages lacked an X zone. The decrease in X zone thickness with age was most evident when expressed relative to organ weight. In conclusion, the thickness of the outer three adrenocortical zones is affected by endocrine changes associated with pregnancy and lactation but not by age. The thickness of the X zone is an index of growth and maturation in nulliparous female DDD mice less than one year of age.

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Neural progenitor cells in the dentate subgranular zone (SGZ) produce new cells all through life via proliferation. We observed differences in neuroblasts using doublecortin (DCX, a marker of neuronal differentiation) in the SGZ in variously aged dogs (German shepherds). In the 1-year-old group, DCX-immunoreactive (⁺) cells were abundantly observed in the SGZ: These cells had processes extending into the molecular layer. In the 3-year-old group, DCX⁺ cells were decreased by 53.0% compared to that in the 1-year-old group, and DCX⁺ processes were also markedly decreased. In the 6 and 8-year-old groups, DCX⁺ cells were decreased by 34.3% and 62.9% vs. the pre-aged group. In the 8-year-old group, DCX⁺ cells were decreased by 86.4% compared to that in the 1-year-old group. In the 12-year-old group, DCX⁺ cells and processes were nearly disappeared. This suggests that DCX⁺ cells processes significantly decreased at 3 years in the SGZ of the German shepherd.

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Uterine natural killer (uNK) cells have roles for immune responses at the feto-maternal interface in mice. We studied the effects of β₂-microglobulin (β₂m) and perforin on proliferation and differentiation of uNK cells in pregnancy, using β₂-microglobulin-deficient (β₂m^-/-) mice and perforin-deficient (P^-/-) mice. The cell population of uNK cells in the metrial gland of P^-/- mice was tended to be higher than the control B6 mice. The cell population of uNK cells in the metrial gland of β₂m^-/- mice was significantly increased at Day 12 of pregnancy comparing to B6 and P^-/- mice. On the other hand, the cell population of uNK cells in the decidua basalis of β₂m^-/- mice was tended to be lower than B6 and P^-/- mice. These results indicate that β₂m may be involved in proliferation of uNK cells in the metrial gland, and that β₂m may affect the maturation of uNK cells in the decidua basalis.

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A bacterial strain isolated from the oral cavity of a healthy dog revealed an unusual colony formation in nebular appearance on agar plates. The isolated bacterial strain was Gram-positive, spore-forming rod with peritrichous flagella, and grown under aerobic conditions, but unable to grow at 45°C. The strain was tentatively classified as Paenibacillus alvei according to the biochemical properties and the 16S rRNA gene sequence. The isolate exhibits collective locomotion on solid agar plates. The bacterial motility was inhibited with EDTA and was restored by adding magnesium. We concluded that magnesium ion is essential for collective locomotion of P. alvei. This suggests that EDTA is useful for inhibition of biofilm formation.

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Adiponectin is an adipokine that is specifically expressed in adipose tissues, directly sensitizes the body to insulin via specific receptors and its decreased plasma concentration is responsible for insulin resistance in obese humans. Diabetes is an important problem also in veterinary medicine, and feline diabetes is very similar to human type 2 diabetes, in which obesity is an important risk factor. In the present study, We obtained cDNA clones corresponding to feline adiponectin and adiponectin receptor 1 (AD-R1), whose nucleotide and deduced amino acid sequences were highly identical to those of other species, especially, the extra-cellular domain of feline AD-R1 was almost identical to that of human AD-R1. Adiponectin mRNA was exclusively detected in the adipose tissue, but AD-R1 was in all tissues tested in this study. Next, plasma samples were collected from 22 cats visiting veterinary practices. They were divided to 2 groups based on a five-point scale body condition score (BCS), such as normal group (BCS ranged from 2.5 through 3.5) and obese group (BCS ranged from 4.0 through 5.0). Plasma adiponectin in obese cats (7.2 ± 1.5 μg/ml) was significantly lower than that of normal cats (18.0 ± 3.2 μg/ml). These results suggest that adiponectin may be responsible for insulin function also in the cat, and it can be a target molecule for treatment of obesity and diabetes in cats.

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Reticulated platelets (RP) are young platelets that contain residual RNA, and measurement of RP has been to assess thrombopoiesis. In the present study, flow cytometric counts of RP were compared using paired specimens elicited from dogs with various platelet counts by different RP collection procedures, the whole blood method (WBM) and platelet rich plasma method (PRPM). The flow cytometric counts of RP for the specimens collected by WBM showed good and stable agreement with those taken by PRPM from the same canine subjects. The result revealed that WBM, as well as PRPM, can be used clinically to determine RP levels in dogs with abnormal platelet counts.

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This study evaluated the relationship between the serum vitamin A level and immune function in seventy non-diseased Japanese Black (JB) cattle during their fattening stages. The animals were divided into two groups, a Low Vitamin A (VA) group (N=9) with below 30 IU/dl of serum VA and a Control group (N=61). Blood samples were collected for biochemical analysis and examination of the leukocyte population and cytokine mRNA expression. The numbers of CD3⁺WC1⁺ T cells and MHC class-ll⁺CD14^- B cells were significantly lower in the Low VA group than in the Control group (P<0.05). The IFN-γ/IL-4 rate was significantly lower in the Low VA group, while IL-4 was higher and IFN-γ was lower in the Low group compared with the Control group. This study indicated that immune function imbalance was present in JB cattle with low serum VA levels during the fattening stage.

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A 4-year-old female miniature dachshund presented with a history of progressive decrease in vision, neck pain, and ataxia for which an MRI was performed 21 days after the initial consultation. The optic nerves showed isointensities on T1- (T1W) and T2-weighted (T2W) images that were enhanced by the contrast medium. The optic chiasm was swollen. Other parts of the cerebral parenchyma, not only the visual pathway, showed symmetrical hyperintensities on T2W images. Cerebrospinal fluid showed increased anti-GFAP autoantibodies. The dog received corticosteroid therapy despite which she exhibited anorexia, vomiting, and lethargy. Hence, a follow-up MRI was repeated 30 days after the initial consultation in which T2W images showed enlargement of the hyperintense area. The dog died 45 days after the initial consultation. Postmortem pathological examination confirmed a diagnosis of granulomatous meningoencephalomyelitis (GME).

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Enterocytozoon bieneusi is an emerging and clinically significant enteric pathogen in humans associated mainly with chronic diarrhea. It has been found in a variety of wild, domestic and companion mammals and birds. To date, epidemiological surveys of E. bieneusi infection in humans, other mammals and birds have been performed in more than 21 countries in Africa, the Americas, Australasia and Europe. In Asia E. bieneusi has been found in India, Thailand, Vietnam and Korea, but it has been quite unclear whether this pathogen is present in Japan. In the present study, we examined 149 DNAs extracted from 45 human (9 of them HIV-positive) and 104 animal fecal samples by PCR. Two dogs and a cat were positive and their genotypes were found to be dog specific and zoonotic (genotype K) types, respectively. Present study is the first record of E. bieneusi in Japan.

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Canine distemper caused by canine distemper virus (CDV) is a contagious, incurable, often fatal, multisystemic viral disease that affects the respiratory gastrointestinal and central nervous system. Strains Vn86 and Vn99 of CDV were isolated, we believe for the first time, in Vietnam from two 4-month-old autopsied dogs pathologically showing non-suppurative encephalitis with pneumonia, lymphoid depletion and severe gastroenteritis. These strains caused syncytium cytopathic effect in Vero cells and Vero cells expressing canine signaling lymphocyte activation molecules. The titers of cell-associated viruses of both strains were higher than for released viruses. Molecular analysis showed that both new isolates of CDV joined to the group of classic type that is far from the Asia 1 and Asia 2 groups. These results indicated that first isolation and characterization of canine distemper virus in Vietnam with the immunohistochemical examination of the dog.

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Epidemiological investigations suggest that increased age is associated with susceptibility to infection. Pseudomonas aeruginosa (P. aeruginosa) infection and associated exotoxin A (PEA) toxicity have been reported in hospitalized elderly patients and young children with cystic fibrosis. The present study investigated age-related differences in PEA-induced hepatotoxicity in post weaning (PW, 3 weeks), young adult (YA, 12 weeks), and mature adult (MA, 60-64 weeks) rats. PEA (20 μg/kg) was injected intraveneously and mortality, clinical chemistry, hepatic histopathology, TUNEL (Terminal deoxynucleotidyl transferase-mediated dUTP nick end-labelling) and PCNA (Proliferating cell nuclear antigen) staining, and serum cytokine levels were assessed at specific time points, up to 72 hr post-exposure (HPE). Mortality in MA rats was 100% at less than 48 HPE. Serum ALT levels in MA rats were approximately 5-fold greater than levels in PW and YA rats at 36 HPE. MA rat liver histological sections showed diffuse hepatocellular necrosis. In contrast, hepatocellular apoptosis, demonstrable by the TUNEL method, was noted simply in the periportal and midzonal regions from 36 to 48 HPE. Increased morphological mitoses and PCNA-positive hepatocytes were seen in PW and YA rats at 72 HPE. These parameters were correlated with age-dependent significant increases in TNF-α, IL-2, IL-6, and IL-18 levels. These data suggest that inflammatory cytokines play an important role in age-related differences in PEA-induced hepatotoxicity. Moreover, these cytokines might correlate with different patterns histopathologic features at various ages.

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Histopathological examination of clinically long-standing lesions with durations of one year or more in the extremities of two cattle revealed the presence of sarcomas with distant metastases. In case 1, neoplastic cells were fusiform to pleomorphic, stained for no specific differentiation markers, and diagnosed as undifferentiated sarcoma. Neoplastic growth in case 2 was composed of spindle to histiocytoid cells and a significant number of multinucleated giant cells, both of which were immunoreactive to histiocyte markers, and diagnosed as giant cell malignant fibrous histiocytoma. Neoplastic cells of both cases were immunohistochemically positive for nitric oxide-related antigens, which were recognized as markers of inflammation-induced carcinogenesis in human and laboratory animals.

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A Japanese Black bull aged 20 years died following progressive loss of the body weight. Pathological examination disclosed multiple endocrine tumors including thyroid C cell carcinoma with metastases to the cervical lymph nodes and lung, adrenal pheochromocytoma and pituitary chromophobe adenoma in the pars distalis. The serum calcium content was as mildly low as 8.0 mg/dl at the terminal stage. The bull had daily ingested the ration containing 1.9 times the recommended calcium amount for 8 years and 120,000 units of vitamin D₃ for 5 years prior to death. The long-term dietary intake of moderately excessive calcium with vitamin D₃ might be related to the pathogenesis of the thyroid C cell carcinoma.

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A 5-year-old female miniature dachshund presenting with persistent vomiting and diarrhea had two concurrent rare pathological conditions: systemic candidiasis and mesenteric mast cell tumor with multiorgan metastases. Neoplastic mast cells formed mass in the mesentery of the cecal-colonic region and were also found in the liver, spleen, kidneys, lungs, adrenal grands, ovaries, bone marrow and other tissues. The cells had intracytoplasmic granules with metachromasia and were immunohistochemically positive for c-kit and histamine. Granulomatous lesions with fungal organisms were present in the heart, lungs, kidneys, pancreas, subserosal and surrounding adipose tissue of the duodenum, thyroid glands and mesenteric mass, and phagocytosed organisms were detected in the liver and bone marrow. Bacteriologically and immunohistochemically, the fungi were consistent with Candida albicans.

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The potential roles of the spleen in lipid metabolism have been debated for the last 2 decades. Although there are some discrepancies among investigations, they are in agreement on the point that the spleen has roles in lipid metabolism. In the present study, role of the spleen in lipid metabolism was investigated by use of a hereditary asplenic mouse strain carrying a Dominant hemimelia (Dh) mutation. In studies on females, asplenic mice (Dh/+) had significantly lower plasma high-density lipoprotein-cholesterol (HDL-CHO) levels than did eusplenic mice (+/+) on a chow diet. On a high-fat diet, Dh/+ had significantly higher HDL-CHO than did +/+. In studies on Y-consomic strains (DH-Chr Y), DH-Chr Y-Dh/+ had significantly lower values than did DH-Chr Y-+/+ for all traits. For body weight and HDL-CHO, there were significant differences in mean trait values among DH-Chr Y-+/+, suggesting that Y-linked genes affect these traits. Furthermore, pattern of distribution of mean trait values among Y-consomic strains largely differed between DH-Chr Y-+/+ and DH-Chr Y-Dh/+, suggesting the presence of interaction between Dh and Y-linked genes. The present study shows that Dh has effects on lipid metabolism. Although Dh has multiple phenotypic effects it is possible that the change in lipid levels is affected in part by the absence of the spleen.

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All cattle imported from the United Kingdom to Japan since 1980 and slaughtered before 2002 were traced (n=33), and the number of cattle that were possibly infected with BSE and entered the animal feed chain was calculated. Because there was no effective system to avoid recycling of the BSE agent via animal feed until the early 1990s, of the 33 cattle imported from the UK into Japan, most probably 7 or 8 were infected and entered the animal feed chain, 2 of which entered the animal feed chain in each of 1992 and 1993. In terms of infectivity, 400-550 cattle oral ID₅₀ of the BSE agent entered the feed chain in each of these years. The amount of infectivity that entered the feed chain in 1989, 1991 and 1995 was smaller but still substantial, suggesting that the BSE agent might have entered the Japanese feed chain in any of these years.

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Antivascular photodynamic therapy (PDT) suppresses tumor growth and prolonged the survival in solid tumor-bearing mice. The purpose of this study was to assess the efficacy of antivascular PDT using BPD-MA for treatment of oral and nasal tumors in 14 dogs. At 15 min after initiating intravenous infusion of 0.5 mg/kg benzoporphyrin derivative monoacid ring A, tumors were irradiated with laser light at 690 nm emitted by a diode laser. The 1-year survival rate of 7 dogs with oral tumors was 71%. The 1-year survival rate of 7 dogs with nasal tumors was 57%. Imaging of each tumor was performed by using angiographic computed tomography before and after each antivascular PDT. Contrast-enhanced tumors were observed before antivascular PDT, but these tumors were not enhanced with contrast medium following antivascular PDT. Antivascular PDT is suggested to be a promising method for dogs with oral and nasal tumors that cannot be effectively treated with current antitumor therapies.

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Fibrocartilaginous embolism (FCE) is a disorder of acute onset that presents with nonprogressive ataxia. We performed a retrospective examination of FCE of the spinal cord diagnosed by characteristic clinical findings and magnetic resonance imaging (MRI) in 26 dogs. In the present study, treatment consisting of physiotherapy alone, or this in combination with corticosteroid administration, was initiated immediately following diagnosis of FCE. Age at onset and the gender ratio in the present study closely correlated with those previously reported. In the present study, 88% of the dogs that developed FCE were small- to medium-sized, which is different from previously reported studies. There is a possibility that FCE also develops relatively frequently in small- to medium-sized dogs. No significant difference was observed between the physiotherapy alone and the physiotherapy and corticosteroids groups of dogs. FCE development has been reported predominantly at the vertebral levels C6-T2 and L4-S3 and less frequently at C1-5 and T3-L3. However, in the present study, FCE developed predominantly at T3-L3. FCE developed at T3-L3 or C1-5 in 69% of the cases in the present study, suggesting that there is relatively frequent development of FCE at these vertebral levels. The recovery time of T3-L3 was the shortest (10.2 ± 7.4 days), and that of C1-5 was next-shortest (15.8 ± 5.4) in this study. This suggested the possibility that the detection ratio of cases was low, because the symptoms in cases of FCE that has developed in C1-5 and T3-L3 would have improved before inspection in the secondary institution, where the MRI and diagnosis were performed.

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A male Pomeranian dog aged 1 year and 8 months was presented for evaluation of severe systolic ejection, cardiac murmur and syncope on excitation. Supravalvular pulmonary stenosis was diagnosed. An echocardiogram showed a supravalvular membranous stricture and a severely increased pulmonary arterial velocity in the stricture (6.49 m/s, pressure gradient of 169 mmHg). The supravalvular stricture was surgically removed by pulmonary arteriotomy with the heart beating using a cardiopulmonary bypass system. The postoperative pulmonary arterial velocity at the narrow area decreased to 3.80 m/s, and the pressure gradient decreased to 57.7 mmHg. Six months after the operation, there were no signs of restenosis, and the dog was in good condition without syncope. Surgical correction of pulmonary stenosis with the heart beating using a cardiopulmonary bypass system is useful because of the improvement it brings in safety and reliability.

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A 3-year-old spayed, female, domestic shorthair cat presented in the recumbent position. Clinical examination revealed decreased consciousness and ataxia. Neurological findings suggested a lesion in the forebrain and brainstem, and magnetic resonance imaging (MRI) of the brain was performed. A nodular lesion approximately 1 cm in diameter in the left parietal lobe, overlying the temporal lobe, was observed on MRI scans. T2-weighted images revealed iso- to slightly low-intensity signals in the cerebral white matter. The lesion was detected as low-intensity signals by T1-weighted images and was emphasized by enhanced T1-weighted images. The cat died on the 3rd hospital day. By complete pathological examinations including immunohistochemical investigations, the cat was diagnosed as primary intra-axial B-cell lymphoma.

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The purpose of this study was to obtain the computed tomography (CT) data for the hip joints of 22 Border Collies. The dorsolateral subluxation (DLS) score, lateral center edge angle (LCEA), dorsal acetabular rim angle (DARA) and center distance (CD) index were measured on the CT images in a weight-bearing position. Radiographic Norberg angle (NA) was also measured. The mean values were 45.7 ± 10.2% for DLS score, 85.9° ± 10.3 ° for LCEA, 18.5° ± 7.3 ° for DARA, 0.40 ± 0.17 for CD index and 102.7° ± 6.9° for NA. Since the DLS score and LCEA showed strong correlation, combined use of these parameters might improve diagnostic accuracy. We consider CT evaluation in a weight-bearing position to be a useful method for multidirectional evaluation of hips.

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We describe a high-performance liquid chromatographic method for determining ustiloxin A, a mycotoxin produced by Ustilaginoidea virens, in forage rice silage. Lyophilized silage samples were ground and extracted with water. The extracts were purified by solid-phase extraction and subjected to high-performance liquid chromatography using an octadecylsilane-bonded column. Separated ustiloxin A was detected with ultraviolet (UV) absorption at 254 nm. The limit of quantitation for ustiloxin A in silage found to be 2.5 mg/kg. The present method can be used for routine monitoring of the contamination of ustiloxin A in forage rice silage.

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The surface glycoprotein (G) of Borna disease virus (BDV) plays central roles in the process of viral entry. BDV G is cleaved by cellular furin-like proteases into two components, GP1 and GP2. Although GP1 is involved in the virus entry into cells, the binding activity of GP1 to cells is unknown. Therefore, we expressed the wild-type GP1 and a variety of GP1 deletion mutants that were FLAG-tagged at the C-terminus in human embryonic kidney 293T cells. These proteins were then purified using an anti-FLAG antibody and evaluated for their ability to bind to cell lines. GP1 bound to BDV-permissive cells but not to non-permissive cells. GP1 also inhibited BDV infection via its binding to cells. This binding assay should prove useful to map the receptor-binding domain of BDV.

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