The phylogenic significance of the subdivision of dual olfactory system is reviewed mainly on the basis of our findings by electron microscopy and lectin histochemistry in the three amphibian species. The dual olfactory system is present in common in these species and consists of the projection from the olfactory epithelium (OE) to the main olfactory bulb (MOB) and that from the vomeronasal epithelium (VNE) to the accessory olfactory bulb (AOB). The phylogenic significance of subdivisions in the dual olfactory system in the amphibian must differently be interpreted. The subdivision of the MOB into its dorsal region (D-MOB) and ventral region (V-MOB) in Xenopus laevis must be attributed to the primitive features in their olfactory receptors. The middle cavity epithelium lining the middle cavity of this frog possesses both ciliated sensory cells and microvillous sensory cells, reminding the OE in fish. The subdivision of the AOB into the rostral (R-AOB) and caudal part (C-AOB) in Bufo japonicus formosus must be regarded as an advanced characteristic. The lack of subdivisions in both MOB and AOB in Cynops pyrrhogaster may reflect their phylogenic primitiveness. Since our lectin histochemistry to detect glycoconjugates expressed in the olfactory pathway reveals the subdivisions in the dual olfactory system in the amphibian, the glycoconjugates may deeply participate in the organization and function of olfactory pathways in phylogeny.

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The details of the embryonic and postnatal differentiation of the olfactory epithelium (OE) and vomeronasal organ (VNO) were examined by light and electron microscopy in the Syrian hamster. At 10 days of gestation, the nasal placode is invaginated to form the olfactory pit on either side at the rostral end of the embryo. Abundant mitotic figures are observed near the free surface of the epithelium lining the olfactory pit. At 11 days of gestation, the mass of the epithelium lining a recess is separated from the medial wall of the olfactory pit to form the VNO. At 13 days of gestation, mitotic figures become observable in the basal layer of the vomeronasal sensory epithelium (VSE) in addition to the superficial to middle layers, while in the OE mitotic figures are observed mainly in the middle to basal layer. At 1 day after birth, the OE is almost complete in differentiation. On the other hand, the VSE differentiate slowly to retain some immature properties even at 10 days after birth. These findings suggest that the olfactory function seems to be solely ascribed to the OE for a while after birth. The significance of mitotic figures are discussed in the course of development with special reference to the origin of the nasal placode from the central nervous system.

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Although it has been reported that specific proteins are present to take charge in the gustation in the taste buds, there have been only a few reports on the distribution of glycoconjugates binding to glycoproteins on the cellular membranes of the taste cells. In the present study, therefore, binding patters of 24 biotinylated lectins were examined in the three types of lingual papillae in five species of mammals belonging to different orders: cow (artiodactyl), horse (perissodactyl), monkey (primate), dog (carnivore) and mouse (rodent). As the results, lectin binding patterns were different among circumvallate, foliate and fungiform papillae, among the cells of the taste buds, and among animal species. These findings suggest that the different binding patterns of the lectins in the taste papillae and taste bud cells may be involved in different sensitivities of taste among mammalian species.

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Mycoplasma hyorhinis (M. hyorhinis) exerts multiple effects on cell metabolisms including apoptosis mediated by their endonucleases and nitric oxide production in vitro. Although AsA is preferable to health in general because of its reactive oxygen species scavenging activity, we found that in a human carcinoma cell line AZ-521 infected with M. hyorhinis, apoptosis was enhanced by addition of L-ascorbic acid (AsA) to the cell cultures. No significant differences were evident between the AZ-521 cells with and without AsA (AsA-) after 24 hr of incubation in the mitochondrial fluorescence. M. hyorhinis-infected AZ-521 cells treated with AsA (AsA +) have developed distinct DNA ladders as compared to the control cells AsA- after 24 hr of incubation. Marked cytopathic effects were rather apparent in AsA-treated cells than in control cells AsA- after 24 hr. Our data demonstrate that AsA addition to cell cultures enhances apoptosis induced by M. hyorhinis infection. We suggest that the presence of another external apoptotic pathway by M. hyorhinis infection.

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Formalinized Aeromonas (A.) hydrophila agglutinated loosely with the formalinized American channel catfish erythrocytes (FACCE), while live A. hydrophila agglutinated tightly with the FACCE. There was a significant difference on the number of attaching bacterial cells to the FACCE (p<0.01) (n=40 erythrocytes) between formalinized and live A. hydrophila. The other bacteria such as Salmonella (S.) Typhimurium ST-5, Escherichia (E.) coli V-517 and Staphylococcus (S.) hyicus ATCC1249 used in this experiment did not attach the FACCE.

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Chemokines are important regulators of the selective recruitment of inflammatory cells into sites of allergic inflammation. Since canine atopic dermatitis (AD) shares many clinical features of human AD, patterns of chemokine production in dogs may also be similar with those in humans. The aim of this study was to examine mRNA expression of CCL27 and CCL28 in lesional skin of dogs with AD to demonstrate similarity of chemokine production with human counterparts. RNA was extracted from skin biopsy specimens of 12 dogs with AD. The mRNA expression of CC chemokines (CCL4, CCL19, CCL20, CCL21, CCL24, CCL27 and CCL28) was analyzed by quantitative real-time PCR and was compared between lesional and non-lesional skin. Seven types of chemokines examined were constitutively expressed in both lesional and non-lesional skin. It was found that mRNA expression levels of CCL27 and CCL28 among the chemokines were significantly different between lesional and non-lesional skin (P<0.05). Expression level of CCL27 mRNA in lesional skin was significantly lower than that in non-lesional skin. On the other hand, CCL28 mRNA expression in lesional skin was found to be higher than that in non-lesional skin. These results suggest that CCL28 but not CCL27 may play important roles in immunopathogenesis of canine AD, indicating that experimental canine study may provide additional information that can be extrapolated to human AD.

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We studied the effect of a small volume of 7.2% hypertonic saline solution (HSS) or HSS with 6% dextran 70 (HSD) on hemodynamic status, especially on cardiac contractility, in anesthetized dogs using the left ventricular end-systolic volume index (ESVI) and ejection fraction (EF), which can be obtained in noninvasive echocardiography. In the present study, the mean values of ESVI were unaffected by HSS and HSD infusion, whereas the left ventricular end-diastolic volume index (EDVI) was markedly and significant increased. As a result of the changes in EDVI but not in ESVI, EF increased transiently and significantly in the HSS and HSD group, whereas no such significant change was observed in the dogs that received isotonic saline solution. In addition, as a result of the increases in cardiac index but not arterial pressure, system vascular resistances (SVR) decreased transiently and significantly in the HSS and HSD groups, whereas no such significant change was observed in the ISS group. Therefore, the positive inotropic effects of HSS and HSD may be attributable to the increase in left ventricular preload and decreases in SVR rather than direct changes in myocardial contractility.

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To investigate the effect of hoof trimming before the dry period, the hooves of 10 cows (trimmed group) were trimmed at 79.6 ± 8.6 days before parturition and the hooves of 52 cows were left untrimmed (control group). Blood biochemistry and hormone concentrations were investigated for 6 cows from each group. The daily milk yield after parturition in the trimmed group tended to be higher than that of the control group. Between 0 and 30 days after parturition, the levels of non-esterified fatty acids were significantly lower stet, and the plasma glucose and glucose disposal rates were significantly higher in the trimmed group. The plasma cortisol concentration was stable before and after parturition in the trimmed group. Hoof trimming before the dry period appears to reduce stress and maintain the nutritional conditions of perinatal dairy cows.

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ORP150 is a hypoxic stress-induced protein located in the endoplasmic reticulum. Transgenic mice overexpressing ORP150 (ORP-Tg) exhibit vacuolar degeneration in the heart. To determine whether vacuolization is present in skeletal muscle, we pathologically examined ORP-Tg mice. After 60 days of age, severe vacuolization was found in the soleus muscles of the hind legs of the ORP-Tg mice. Immunohistochemical staining of ORP150 revealed co-localization of ORP150 and vacuolization in the affected cells. Electron microscopy revealed a marked increase in the number of rough-surfaced endoplasmic reticula (rER) and distention of the cisterna. These findings suggest that overexpression of ORP150 causes accumulation of ORP150 in the rER, resulting in vacuolar degeneration in the skeletal muscle of ORP-Tg mice.

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Using microPET and ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) as a tracer, we investigated regional brain activation in a rat model of visceral hypersensitivity induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS). TNBS injection into the proximal colon through laparotomy resulted in a significant, sustained decrease in the pain threshold to mechanical distention of the distal colon, indicating a phenomenon referred to as visceral hypersensitivity. When TNBS-induced colonic hypersensitivity was fully developed, all the TNBS-treated rats presented characteristic pain behaviors in response to colonic distention at previously innocuous pressure (0-35 mmHg) that produced no abdominal pain in sham-operated control animals. In microPET study, colonic distention at the normally non-painful pressure produced significant increases in ¹⁸F-FDG uptake in the thalamus and sensory cortex I of TNBS-treated rats. Since the increases in ¹⁸F-FDG uptake in the brain regions were completely abolished by an analgesic dose of morphine (375 μg/kg, s.c.), it is most likely that the regional brain activation detected by microPET is a pain-related central event. The pharmacological and microPET data indicate that colonic distention at the normally non-painful pressure activates specific brain regions in rats with TNBS-induced visceral hypersensitivity, and the microPET protocol described here could provide an objective measure to test visceral analgesic compounds.

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Fluconazole (Fcz) is successfully used in human organ transplant patients as an antifungal therapy. However, Fcz can increase the cyclosporine (CsA) trough level and lead to CsA nephrotoxicity. In canine renal transplantation, CsA has been used as a major immunosuppressant, and it is important to control its trough level. However, the interaction of Fcz with CsA has not yet been reported in dogs. In this study, the effect of Fcz treatment on the pharmacokinetics of CsA in four healthy beagles was investigated using a four-period crossover design. The treatments included CsA alone (A), CsA + multiple-dose Fcz 50 mg (B), CsA + multiple-dose Fcz 25 mg (C) and CsA + single-dose Fcz 50 mg (D). Blood CsA concentrations were measured at 0.5, 1, 2, 4, 6, 8, 10, 12 and 24 hr after CsA administration. The AUC_0-12 and C_max values for treatment B were significantly higher than those for the other treatments. In particular, the AUC_0-12 of treatment B was about two times higher than that of treatment A. Fcz administration did not significantly prolong the half-life or mean residence time of CsA. The results of our study show that administration of multiple therapeutic doses of Fcz can significantly increase the CsA blood concentration, which might partially depend upon the Fcz blood concentration. When Fcz is used in CsA-based canine renal transplantation, it may be necessary to adjust the CsA trough level by decreasing the dose.

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Clinical pharmacokinetic profiles were investigated following intramuscular (i.m.) administration to pigs with a commercial tylosin-florfenicol combination product at a dose of 2.5 mg/kg tylosin and 5 mg/kg florfenicol or 10 mg/kg tylosin and 20 mg/kg florfenicol. The quantitation limit (QL) of florfenicol was 0.1 μg/ml, the inter-day and intra-day precision (CV%) were both beow 10%. The quantitation limit (QL) of tylosin was 0.05 μg/mL. The pharmacokinetic characteristics after i.m. doses were fitted by a one compartment open model. A fourfold decrease in the normal dose of each drug (20 mg/kg to 5 mg/kg for florfenicol, and 10 mg/kg to 2.5 mg/kg for tylosin) resulted in a corresponding two fold decrease in each drug of the maximum plasma concentration (C_max) and the area under curve (AUC) values.

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The aim of this study was to compare thiobarbituric acid reactive substances (TBARS) concentrations in serum, plasma with heparin (heparin plasma), and plasma with ethylenediaminetetraacetic acid disodium salt (EDTA plasma) as anticoagulants from dairy cattle. Serum, heparin plasma, and EDTA plasma TBARS were not sufficiently strongly correlated to allow accurate prediction of one set of values from the other. Heparin plasma TBARS concentrations were found to be lower, and were affected by the duration of mixing during the assay process. The results suggest that it is necessary to differentiate TBARS concentrations between different sample types such as serum, heparin plasma, and EDTA plasma. For measurements of TBARS concentrations in cattle, EDTA plasma samples may be more suitable than the other samples.

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Sparing effects of carprofen and meloxicam with or without butorphanol on the minimum alveolar concentration (MAC) of sevoflurane were determined in 6 dogs. Anesthesia was induced and maintained with sevoflurane in oxygen, and MAC was determined by use of a tail clamp method. The dogs were administered a subcutaneous injection of carprofen (4 mg/kg) or meloxicam (0.2 mg/kg), or no medication (control) one hour prior to induction of anesthesia. Following the initial determination of MAC, butorphanol (0.3 mg/kg) was administered intramuscularly, and MAC was determined again. The sevoflurane MACs for carprofen alone (2.10 ± 0.26%) and meloxicam alone (2.06 ± 0.20%) were significantly less than the control (2.39 ± 0.26%). The sevoflurane MACs for the combination of carprofen with butorphanol (1.78 ± 0.20%) and meloxicam with butorphanol (1.66 ± 0.29%) were also significantly less than the control value after the administration of butorphanol (2.12 ± 0.28%). The sevoflurane sparing effects of the combinations of carprofen with butorphanol and meloxicam with butorphanol were additive.

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The causes of early degeneration and calcification of the nucleus pulposus in the chondrodystrophoid dog are poorly understood, and the underlying molecular mechanism of this process has not yet been clearly defined. Type X collagen is one of the key molecules in endochondral bone growth and development, especially matrix calcification. The relationship between type X collagen and disc degeneration and calcification in chondrodystrophoid dogs has not yet been studied. We analyzed the expression of type X collagen in degeneration and calcification of the intervertebral disc in chondrodystrophoid dogs, using type X collagen immunohistochemistry. Control intervertebral discs were collected from five dogs (4 female, 1 male, average age 1.3 years, beagle breed). Degenerated intervertebral discs were surgically removed from 11 canine patients with intervertebral disc extrusion (1 female, 10 male, average age 5.1 years, dachshund breed) in Nippon Veterinary and Animal Science University. All extruded disc samples showed hypertrophic changes and clustering of cells, typical features observed in the degenerated nucleus pulposus. The relative expression of type X collagen in the degenerated nucleus pulposus (84.3 ± 11.0%) was significantly increased compared to the control nucleus pulposus (5.4 ± 5.4%). Our findings suggest that type X collagen might contribute to the development of degeneration or calcification in the nucleus pulposus of the chondrodystrophoid dog.

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We found odontoclastic resorptive lesions on premolars and molars in a 4- year-old miniature dachshund. The teeth had been extracted because the dentin was resorbed. In some teeth, the roots had been replaced by hard tissue, and so we amputated the crowns and curetted roots and alveolar bone. Histopathological examination revealed that the dentin was resorbed by odontoclasts and was replaced with bony tissue. Ten months later we found resorptive lesions in other teeth, and we treated them along with the first treatment. At the time of writing, since this is the first report of a dog with the same lesion in other teeth after the first treatment, we hope to establish better treatment and prevention methods.

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High mortality in female pigs on breeding farms is a critical problem in the U.S. swine industry. The objectives of this study were to determine whether female pig mortality on Japanese commercial farms increased; to investigate correlations between the mortality and herd-management factors, especially herd size and lactation length; and to determine herd repeatability in female pig mortality. A five-year annual measurement data between 1999 and 2003 were abstracted from recording files of 113 farms in Japan. The year-effects on measurements were analyzed by using repeated measures data between 1999 and 2003 in mixed-effects linear models. The annual mortalities for female pigs in 1999, 2000, 2001, 2002 and 2003 were 4.93%, 5.25%, 5.40%, 5.32%, and 4.85%, respectively. The year-effect on the female pig mortality was not found for the five years. Neither herd size, lactation length nor other management factors were found to be consistently correlated with female pig mortality for the five years. The repeatability of the mortality was 36.5% on commercial farms. In conclusion, female pig mortality did not increase during these five years in Japan. Herd size and lactation length were not risk factors for female pig mortality.

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We studied the associations of the weaning litter weight (WLWt) and number of pigs weaned (PW) with measurements of postweaning reproductive performance and examined the repeatability of WLWt, PW and average pig weight at weaning (PIGWt) on commercial swine farms. This study spanned 6 years and was conducted using 57,611 weaning records from 11,574 sows born in 1999 on 92 farms. Variance components analysis was used to determine the repeatability of measurements of lactational performance. Mixed-effects models were used to analyze the associations of measurements of lactational performance with farrowing rate and weaning-to-first-mating interval. The values for repeatability of WLWt, PIGWt and PW were 0.31, 0.34 and 0.17, respectively. No differences in weaning-to-first-mating intervals were found among the five PW groups (≤ 6, 7 to 8, 9 to 10, 11 and 12 to 14 pigs) or among the three WLWt groups (≤ 48.0, 48.0 to 69.0 and ≥ 69.0 kg). Sows with 12 to 14 PW had farrowing rates similar to those with 9 to 11 PW. Sows with a WLWt ≥ 69.0 kg had the highest farrowing rate (P<0.01). However, sows with 11 PW had an approximately 100 to 200 g lighter PIGWt than those with 4 to 10 PW (P<0.01). This study suggests that increased WLWt and PW do not impair postweaning reproductive performance, but instead decrease PIGWt.

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To examine the ovarian response to Arcanobacterium pyogenes (A. pyogenes) in uterus, bacterial solution was infused into the uteri of cows, and the follicle and corpus luteum (CL) development were monitored with a real-time ultrasound instrument. In addition, the plasma concentrations of progesterone (P₄) and 13, 14-dihydro-15-keto-PGF_2α (PGFM) were determined. A 10 ml bacterial solution that contained A. pyogenes (8 to 15 × 10⁸ CFU/ml) was infused into the uterus of eight cows transcervically three days after natural ovulation. As a control, sterile physiological saline was infused into 4 other cows. The dominant follicle developed normally in 8 cows after bacteria inoculation. In 4 of these 8 cows, the developing CL regressed, and the first wave dominant follicles, which normally become atretic, ovulated after the inoculation. In the remaining 4 cows, the CL did not regress. The PGFM concentration increased transiently in all 8 cows after the infusion. The mean PGFM concentration of the cows with a regressed CL was significantly lower (P<0.01) than that of the cows whose CLs did not regress. In the control cows, there was no regression of developing CLs, no ovulation of first wave dominant follicles and no transient increase in PGFM after the infusion of sterile physiological saline. These results show that infusion of A. pyogenes into the uterus did not affect folliculogenesis and might have induced PGF_2α production from the uterus.

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In the present study, the correlations among age, body weight, scrotal circumference (SC), semen quality and peripheral testosterone and estradiol-17β (E₂) concentrations were investigated in pubertal (n=5) and postpubertal (n=7) groups of Holstein bulls over a 6 week period. There were significant positive correlations (P<0.01) among age, body weight and SC in both groups, and similar significant correlations between sperm motility and SC in pubertal bulls (P<0.01) and between sperm concentration and SC in postpubertal bulls (P<0.05). The sperm motility after collection (P<0.05) and after freezing and thawing (P<0.01) of the postpubertal bulls correlated positively with the E₂ concentration. Estrogen may be important for the function of postpubertal bull testes, in which it may regulate spermatozoa motility in vivo.

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This paper describes the case of a 2-year-old English Bulldog with severe teratozoospermia that consisted mainly of "Dag-like" defects, which is strong coiling of the tail. Although libido, semen volume and sperm concentration were normal, sperm motility was 5.0%, and 93.3% of spermatozoa exhibited morphological abnormalities affecting the tail. Transmission electron microscopic examination of the spermatozoa revealed strong folding, coiling and fracture of sperm midpieces and tails, axonemal defects and the presence of swollen and unevenly distributed mitochondria. Taking into account the dog's history and examinations and the constantly high percentage of abnormal spermatozoa over time, the defect was considered to be genetic in origin.

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Since the status of endogenous avian leucosis/sarcoma virus (ALSV) infections in Korean broiler chickens is unclear, this study examined embryonated eggs obtained from broiler farms and Korean native chicken breeds in Korea using PCR with the primer sets specific for endogenous ALSVs. The PCR assays detected the genomes of EAV, ev, ev/J and ART-CH belonging to the endogenous ALSV from all embryos tested. Phylogenetically, the Korean EAV genomes were more closely related to the prototype EAV-0 than to the other prototype, E51. The Korean ART-CH elements clustered together but were distinct from the prototype ART-CH clones, 5 and 14. Although there was comparatively little divergence in the nucleotide and amino acid sequences of the Korean ev and ev/J genomes compared with the other known ev and ev/J genomes, the Korean genomes had phylogenetically distinct branches. From these results, endogenous genomes are quite prevalent in Korean broiler chickens. In addition, the endogenous genomes circulating in Korean broiler chickens are genetically different from the other known endogenous genomes. These results are expected to provide useful information for the control and establishment of a surveillance system for endogenous ALSVs in Korea.

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