Journal of Veterinary Medical Science
Online ISSN : 1347-7439
Print ISSN : 0916-7250
ISSN-L : 0916-7250
最新号
選択された号の論文の10件中1~10を表示しています
Bacteriology
  • Rathanon KHEMGAEW, Mari OMACHI, Tomoe TAKESADA, Torrung VETCHAPITAK, H ...
    2021 年 83 巻 6 号 p. 889-897
    発行日: 2021年
    公開日: 2021/06/09
    [早期公開] 公開日: 2021/04/14
    ジャーナル オープンアクセス

    Papillomatous digital dermatitis (PDD) is a polymicrobial infection causing lameness in dairy cattle. Culture-independent analysis has shown that Treponema phagedenis is present consistently and predominantly in the lesions. However, the pathogenesis of PDD, especially the tissue penetration pathway, has not been examined. In the present study, we investigated whether T. phagedenis strains isolated from PDD produce proteolytic enzyme (s) for disruption of the epithelial cell barrier and have the ability to translocate in polarized normal human epidermal keratinocytes (NHEK) in vitro. Ten strains of T. phagedenis isolated from lesions did not show proteolytic activity on modified skim milk agar, although a human strain of T. denticola used as a control showed such activity. The integrity of tight junctions was monitored by measurement of transepithelial electrical resistance (TER). The TER values after inoculation of the T. phagedenis strains examined did not change during the experimental period; however, apical to basolateral translocation of T. phagedenis was confirmed after 24 hr by microscopy and Treponema-specific PCR. We further confirmed that translocation of T. phagedenis was accelerated by co-inoculation with live T. denticola, but not with heat-killed organisms. Furthermore, tight junction ZO-1 protein was not lost intensity after inoculation with T. phagedenis and the organism was observed in NHEK cells using a florescence microscope. These results suggest that T. phagedenis strains may translocate via a transcellular route in vitro and that the invasion is accelerated by other bacteria, such as T. denticola, producing proteolytic activity.

Internal Medicine
  • Masaki MAEZAWA, Ken-ichi WATANABE, Kotaro MATSUMOTO, Yoshiyasu KOBAYAS ...
    2021 年 83 巻 6 号 p. 898-904
    発行日: 2021年
    公開日: 2021/06/09
    [早期公開] 公開日: 2021/04/09
    ジャーナル オープンアクセス
    電子付録

    Enzootic bovine leukosis (EBL) is typically observed in cattle over 3 years old. However, some cases of EBL onset in young beef cattle have been reported in Japan. The mechanism for early EBL onset is unclear. In Japan, beef cattle are given large amounts of concentrated feed with low vitamin A. Bone morphogenetic proteins (BMPs) are regulators of cell proliferation, differentiation, and apoptosis, and thought to represent one of the key players in tumor malignancy. The purpose of this study was to evaluate the differences in BMP-6 methylation status between EBL beef cattle under 3 years old and other cattle. We investigated the methylation status of the BMP-6 promoter region in 32 EBL beef cattle under 3 years old. We also compared the methylation status of EBL dairy cattle to that of healthy cattle. Median methylation rate of the BMP-6 promoter region in EBL beef cattle under 3 years old was 8.9%, which was significantly higher than that of other groups. Hypermethylation of the BMP-6 promoter region might contribute to early onset of EBL in beef cattle under 3 years old, and animal feeding management practices specific to beef cattle may affect the methylation status of the BMP-6 promoter region.

  • Hitoshi MIZUGUCHI, Tomoki IKEDA, Yumi WATANABE, Shiro KUSHIBIKI, Kenta ...
    2021 年 83 巻 6 号 p. 905-910
    発行日: 2021年
    公開日: 2021/06/09
    [早期公開] 公開日: 2021/04/21
    ジャーナル オープンアクセス

    The effects of anti-lipopolysaccharide (LPS) antibody on rumen fermentation and LPS activity were investigated during subacute ruminal acidosis (SARA) challenge. Eleven Holstein cattle (164 ± 14 kg) were used in a 3 × 3 Latin square design. Cattle were fed a roughage diet on days −11 to −1 (pre-challenge) and day 2 (post-challenge), and a high-grain diet on days 0 and 1 (SARA challenge). For 14 days, 0-, 2-, or 4-g of anti-LPS antibody was administered once daily through a rumen fistula. Ruminal pH was measured continuously, and rumen fluid and blood samples were collected on days −1, 0, 1, and 2. Significantly lower ruminal LPS activity on day 1 was observed in the 2- and 4-g groups than those in the 0-g group. In addition, significantly higher 1-hr mean ruminal pH on SARA challenge period (days 0 and 1) was identified in the 4-g group than in the 0-g group. However, rumen fermentation measurements (total volatile fatty acid [VFA], VFA components, NH3-N and lactic acid) and peripheral blood metabolites (glucose, free fatty acid, beta-hydroxybutyrate, total cholesterol, blood urea nitrogen, aspartate aminotransferase and gamma-glutamyl transferase) were not different among the groups during the experimental periods. Therefore, anti-LPS antibody administration mitigates LPS release and pH depression without the depression of rumen fermentation and peripheral blood metabolites during SARA challenge in Holstein cattle.

  • Munekazu NAKAICHI, Toshie ISERI, Hiro HORIKIRIZONO, Misa KOMINE, Harum ...
    2021 年 83 巻 6 号 p. 911-915
    発行日: 2021年
    公開日: 2021/06/09
    [早期公開] 公開日: 2021/04/09
    ジャーナル オープンアクセス

    A male 25-month-old Dalmatian dog attended our veterinary hospital because of anorexia and high circulating liver enzyme activities. Abdominal computed tomography showed a slightly small liver with rounded edges, and laparoscopic examination showed that the liver was yellowish. Histopathological examination revealed multifocal necrosis of hepatocytes and severe chronic hepatitis. Rhodanine staining showed severe copper accumulation in hepatocytes and a quantitative analysis of the copper content of the liver showed substantial accumulation (10.3 mg/g dry mass), suggesting a diagnosis of copper-associated hepatitis. Previously reported canine mutation in the COMMD1, the gene responsible for the copper-associated hepatitis in the Bedlington terrier, was not identified. To our knowledge, this is the first report of copper-associated hepatitis in a Dalmatian in Japan.

Laboratory Animal Science
  • Dong-Ju PARK, Ju-Bin KANG, Phil-Ok KOH
    2021 年 83 巻 6 号 p. 916-926
    発行日: 2021年
    公開日: 2021/06/09
    [早期公開] 公開日: 2021/04/21
    ジャーナル オープンアクセス

    Ischemic stroke is a fatal disease that has long-term disability. It induces excessive oxidative stress generation and cellular metabolic disorders, result in tissue damage. Epigallocatechin gallate (EGCG) is a naturally derived flavonoid with strong antioxidant property. We previously reported the neuroprotective effect of EGCG in ischemic stroke. The defensive mechanisms of stroke are very diverse and complex. This study investigated specific proteins that are regulated by EGCG treatment in the ischemic brain damage. Middle cerebral artery occlusion (MCAO) was performed to induce focal cerebral ischemia. EGCG (50 mg/kg) or vehicle was intraperitoneally administered just prior to MCAO. MCAO induced severe neurological deficits and disorders. EGCG treatment alleviated these neurological disorder and damage. Cerebral cortex was used for this study. Two-dimensional gel electrophoresis and mass spectrometry were performed to detect the proteins altered by EGCG. We identified various proteins that were changed between vehicle- and EGCG-treated animals. Among these proteins, isocitrate dehydrogenase, dynamin-like protein 1, and γ-enolase were decreased in vehicle-treated animals, while EGCG treatment prevented these decreases. However, pyridoxal-5’-phosphate phosphatase and 60 kDa heat shock protein were increased in vehicle-treated animals with MCAO injury. EGCG treatment attenuated these increases. The changes in these proteins were confirmed by Western blot and reverse transcription-PCR analyses. These proteins were associated with cellular metabolism and neuronal regeneration. Thus, these findings can suggest that EGCG performs a defensive mechanism in ischemic damage by regulating specific proteins related to energy metabolism and neuronal protection.

Parasitology
Pathology
Surgery
  • Ayano SATO, Toshihide KATO, Motoshi TAJIMA
    2021 年 83 巻 6 号 p. 940-946
    発行日: 2021年
    公開日: 2021/06/09
    [早期公開] 公開日: 2021/04/30
    ジャーナル オープンアクセス

    Flexural and hyperextension deformities are congenital problems in calves. We, therefore, aimed to investigate the distal limb conformation in 1 day- and 28-day-old female Holstein-Friesian (HF) calves (n=21), male Japanese Black (JB) calves (n=15), and female JB calves (n=15). The claw angle of the forelimb dorsal claw wall in a standing position and recorded other parameters, including body weight, withers height, circumference of forelimbs, and flexor tendon thickness in the forelimbs, were measured and compared these between the three groups. At 1 day old, the mean claw angles were 51.1° in female HF calves, 47.0° in male JB calves, and 41.8° in female JB calves; the 95% confidence intervals (CIs) of the claw angles showed large distributions in all three groups. One female HF and one male JB calves showed mild flexural deformity, whereas four JB calves showed hyperextension deformity. At 28 days old, the mean claw angles were 51.7° in female HF calves, 51.2° in male JB calves, and 48.4° in female JB calves; the 95% CIs of the claw angles showed smaller distributions than those at 1 day old in all groups. For all groups, the limb deformities had improved without treatment at 28 days old. As a feature of the breed, female JB calves were apt to show hyperextended deformities inversely proportional to the body weight. These limb deformities healed spontaneously and were thought to be physiological.

Wildlife Science
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