著者

Masatoshi KAMATA Shotaro NAGAHAMA Kei KAKISHIMA Nobuo SASAKI Ryohei NISHIMURA

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

vol.74, no.2, pp.231-234, 2012 (Released:2012-03-02)

参考文献数

13

被引用文献数

8 17

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Behavioral effects induced by intravenous administration of morphine at 0.3, 0.6, 1.2, and 2.4 μg/kg and fentanyl at 5, 10, 20, and 40 μg/kg were evaluated in dogs and cats. In dogs, fentanyl and morphine depressed activity and level of consciousness in a dose- dependant manner. In cats, higher doses of fentanyl stimulated activity temporarily, but excitement, so-called "opioid mania," was not observed. Morphine induced distinctive behavioral changes characterized by sitting with fixed staring, and "opioid mania" was not observed in cats.

著者

Yui KOBATAKE Hiroki SAKAI Hidetaka NISHIDA Yosuke UEMATSU Sadatoshi MAEDA Hiroaki KAMISHINA

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

vol.80, no.8, pp.1277-1280, 2018 (Released:2018-08-22)

参考文献数

14

被引用文献数

3

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An 8-year-old castrated male cat presented with acute ataxia and paresis in all four limbs. The cat also exhibited signs of autonomic nervous system impairment. Magnetic resonance imaging revealed swelling of the brachial plexuses bilaterally. Despite treatment, the cat died after 10 days of treatment. A postmortem examination revealed swollen radial nerves and cervical nerve roots in which infiltration of inflammatory cells was histologically confirmed. Additionally, lymphocytic infiltration was found around the blood vessels of the sciatic nerve bundle and the vagus nerve. Histological features were comparable to previously reported brachial plexus hypertrophic neuritis in a cat. Our case was unique in that the autonomic nerves were also involved in addition to the somatic nerves in all four limbs.

著者

Fumitaka TAKAHASHI Shigenori KOUNO Shinya YAMAGUCHI Yasushi HARA

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

pp.17-0553, (Released:2018-12-24)

被引用文献数

1

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This study investigated cerebral ventricle size and concurrent craniocervical junction abnormality in relation to atlantooccipital overlapping (AOO) in dogs with atlantoaxial instability (AAI). A total of 61 dogs were treated with atlantoaxial ventral fixation. Medical records of each dog, including magnetic resonance (MR) and computed tomography (CT) images, were retrospectively reviewed. CT images were assessed for the presence of AOO and the dogs were then assigned to either an AOO group or a non-AOO group accordingly. CT images were also evaluated to determine the foramen magnum (FM) index. Syringomyelia, cerebellar compression, dorsal compression, and the degree of enlargement of each cerebral ventricle were evaluated using MR images. Of the 61 dogs, 23 had AOO and 38 did not. Furthermore, the ventricle/brain height ratio, the fourth ventricle height/cerebellum length ratio, and the fourth ventricle width/cerebellum length ratio were significantly higher in the AOO group than in the non-AOO group. However, the FM index, third ventricle/brain height ratio, and incidence of syringomyelia did not differ significantly between the two groups. Dogs with concurrent AOO exhibited significantly more dilatation of the lateral and fourth ventricles.

著者

Yusuke WADA Shunsuke NOGUCHI Hiromitsu SASAKI Ai TAKETOMI Mizuho HAMAKAWA Shunsuke SHIMAMURA Terumasa SHIMADA

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

vol.80, no.11, pp.1724-1727, 2018 (Released:2018-11-23)

参考文献数

15

被引用文献数

6

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Canine nasal carcinomas are often treated with radiotherapy. Presence of lysis of the cribriform plate by tumor invasion (stage 4 by modified Adams’s staging system) is a well-known prognostic factor. In this study, dogs with stage 4 disease were divided into two subgroups based on the presence or absence of midline shift of the olfactory or frontal lobes of the brain (Stage 4a: without presence of midline shift. Stage 4b: with midline shift). The median survival time of dogs with midline shift was significantly shorter than that of dogs without midline shift (64 vs. 208 days). Our results indicate that the finding of a midline shift might have a prognostic significance in dogs with nasal carcinoma treated with radiotherapy.

著者

Mami MURAKAMI Takashi MORI Yasuhiro TAKASHIMA Kisaburo NAGAMUNE Junpei FUKUMOTO Katsuya KITOH Hiroki SAKAI Kohji MARUO

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

pp.18-0340, (Released:2018-11-08)

被引用文献数

7

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An 11-year-old cat presented with nasal discharge and lacrimation and was diagnosed with nasal lymphoma. Although the cat showed favorable progression after undergoing chemotherapy, CT imaging demonstrated enlarged pulmonary nodules caused by Toxoplasma gondii. Following the cessation of chemotherapy, the cat was prescribed clindamycin hydrochloride for toxoplasmosis treatment; however, the cat developed kidney lymphoma and died. No T. gondii organisms were observed in the whole body necropsy specimens. It is known that immunocompromised human patients, including those who undergo chemotherapy, are considered at risk for toxoplasmosis. However, the risk of developing toxoplasmosis in cats undergoing chemotherapy is currently unknown. Findings from this case report suggest that cats with chemotherapy-resistant pulmonary masses might have a T. gondii infection rather than metastatic disease.

著者

Yuto SANO Mai MIYAZAKI Rina YAEGASHI Minoru OKAMOTO Arisa MASUKO Seiya MAEHARA Kazuya MATSUDA

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

pp.18-0369, (Released:2018-11-06)

被引用文献数

1

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An 8-year-old castrated Toy poodle presented with swelling and proptosis of the right third eyelid caused by an exophytic mass on the bulbar surface. Histologically, the mass was composed of stratified neoplastic basaloid cells, arranged in nests and interconnecting islands, which were mixed with tubular structures. Immunohistochemically, the basaloid cells were positive for p63 and cytokeratin (CK) 14, and the inner epithelial cells of the tubular structures were positive for CK7, CK8, and CK19. According to these findings, the mass was diagnosed as a basal cell adenocarcinoma. Although basal cell adenocarcinoma is rare in animals, it should be included in the list of differential diagnoses for superficial tumors of bulbar conjunctiva of third eyelid in dogs.

著者

Misato NAKAMURA Toshinori YOSHIDA Ayumi EGUCHI Mari INOHANA Rei NAGAHARA Ayako SHIRAKI Nanao ITO Makoto SHIBUTANI

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

vol.80, no.2, pp.337-340, 2018 (Released:2018-03-02)

参考文献数

7

被引用文献数

2

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An 18-year-old female black leopard (Panthera pardus) showed renal failure, leukocytosis and presence of subcutaneous masses in the lower abdominal region and right shoulder; she eventually died. Histopathological observations included a mammary gland carcinoma with comedo, solid and tubulopapillary patterns in subcutaneous tissue, and highly proliferated tumor cells in systemic organs. The tumor cells were positive for cytokeratin AE1/AE3. The mammary gland tumor was diagnosed as intermediate-grade adenocarcinoma, based on a previously reported histological grading system of feline mammary carcinomas. Chronic interstitial nephritis was estimated to have been ongoing for 5 years, whilst acute necrotic pancreatitis in relation to tumor metastasis could have been the cause of death.

著者

Kenji KUTARA Toshiaki KONNO Hirotaka KONDO Hinako YAMAZOE Satoru MATSUNAGA

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

vol.79, no.12, pp.1947-1951, 2017 (Released:2017-12-06)

参考文献数

14

被引用文献数

1

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A 10-year-old French bulldog presented with an abdominal tumor. Triple-phase helical computed tomography was performed, revealing a hepatic tumor, an enlarged hepatic lymph node, and no masses in other organs. The hepatic tumor demonstrated marked enhancement, similar to that of the aorta in the arterial phase. The tumor had rich vascularization and a hepatic arterio-venous shunt formed between the hepatic artery and middle hepatic vein. The hepatic tumor was surgically removed and histological diagnosis revealed a hepatic carcinoid tumor. During surgery, rapid massive arterial hemorrhage occurred from the site of the incision. The animal died without improvement post-surgery. In the case of an arterio-venous shunt in a hepatic tumor, it is important to be careful to avoid perioperative bleeding.

著者

Hiroto MAEDA Kaori HAYASHI Takayuki ISHIGE Tomohiro SUNAGAWA Shigeko TANIGAWA Mika MISHINA Toshifumi WATANABE Kazuyuki SOGAWA

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

pp.18-0145, (Released:2018-08-09)

被引用文献数

5

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With the increasing number of cats kept as pets, opportunities to treat cats with lower urinary tract disease (LUTD) have recently increased in the clinical veterinary field. Urine samples collected from 50 cats with bacterial cystitis brought to Maeda Veterinary Hospital between August 10, 2015 and March 31, 2017 were used in the study. Sample preparation of the urine was performed using a MALDI Sepsityper kit and rapid BACpro. To identify the isolates, MALDI-TOF MS was performed on an AutoFlex TOF/TOF mass spectrometer. MALDI-TOF MS using rapid BACpro for pretreatment was found to be a quick and reliable method for identification of bacteria from infected urine, with a shortened analysis time enabling earlier and more accurate selection of antibiotics for treatment of feline LUTD.

著者

松葉

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

中央獸醫會雑誌 (ISSN:18839096)

巻号頁・発行日

vol.32, no.9, pp.519-519, 1919

著者

Ye-In OH Doo-Sung CHEON Jung-Keun LEE Mi-Hyun CHOI Sun-Young HWANG Hyun-Wook KIM Byung-Jae KANG Hwa-Young YOUN

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

pp.17-0702, (Released:2018-07-11)

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A 12-year-old neutered male domestic shorthair cat was presented with a 3-year history of multiple nonpruritic, ulcerated, plaque-like skin lesions but no other clinical signs. A systemic examination revealed mild lymphadenopathy. Histopathologic analysis of the skin lesions revealed multicentric basosquamous carcinoma (BSC). Immunohistochemical analysis, PCR, and sequencing detected Felis catus papillomavirus type 2 (FcaPV-2) within the tumors. As BSC is rare in cats, clinical behavior has not been established. To our knowledge, this is the first case report to demonstrate detection of FcaPV-2 within a BSC in a domestic cat.

著者

Naris THENGCHAISRI Chayakrit SINTHUSINGHA Surapong ARTHITWONG Panpicha SATTASATHUCHANA

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

vol.79, no.6, pp.1081-1085, 2017 (Released:2017-06-29)

参考文献数

20

被引用文献数

3

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Evidence suggests that non-domesticated felids inherited the same AB-erythrocyte antigens as domestic cats. To study the possible compatibility of tiger blood with that of other endangered felidae, blood samples from captive tigers and domestic cats were subjected to an in vitro study. The objectives of this study were to (1) identify whether the captive tigers had blood type AB and (2) determine the compatibility between the blood of captive tigers and that of domestic cats with a similar blood type. The anti-coagulated blood with ethylenediaminetetraacetic acid of 30 tigers was examined to determine blood type, and a crossmatching test was performed between tiger and cat blood. All 30 tigers had blood type A. Tube agglutination tests using tiger plasma with cat erythrocytes resulted in 100% agglutination (n=30) with type B cat erythrocytes and 76.7% agglutination (n=23) with type A cat erythrocytes. The 80% of major and 60% of minor compatibilities between blood from 10 tigers and 10 domestic cats with blood type A were found to pass compatibility tests. Interestingly, 3/10 of the tigers’ red blood cell samples were fully compatible with all cat plasmas, and 1/10 of the tiger plasma samples were fully compatible with the type A red cells of domestic cats. Although the result of present findings revealed type-A blood group in the surveyed tigers, the reaction of tiger plasma with Type-A red cell from cats suggested a possibility of other blood type in tigers.

著者

Nanako YAMASHITA-KAWANISHI Ryoma SAWANOBORI Kosuke MATSUMIYA Akiko UEMA James K. CHAMBERS Kazuyuki UCHIDA Hidekatsu SHIMAKURA Masano TSUZUKI Chia-Yu CHANG Hui-Wen CHANG Takeshi HAGA

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

pp.18-0089, (Released:2018-06-05)

被引用文献数

21

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Association of felis catus papillomaviruses (FcaPVs) with feline squamous cell carcinoma (SCC) has been reported worldwide, while there is limited information about FcaPVs in Asia. In this study, 21 feline SCC biopsy samples from cats in Japan were analyzed by PCR with PV consensus primers and type-specific primers for FcaPV type 2 (FcaPV-2), FcaPV-3 and FcaPV-4 designed in this study. Sequence analysis revealed that one sample was FcaPV-3, and two were FcaPV-4. In both FcaPV-4 positive samples, 334th tryptophan in L1 ORF was deleted compared with the reference sequence. Moreover, immunohistochemistry showed that p16 protein was positive in both FcaPV-4 detected samples. This study would contribute to the molecular epidemiological and pathological understanding of FcaPV in Japan.

著者

Keisuke OGUMA Megumi OHNO Mayuko YOSHIDA Hiroshi SENTSUI

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

pp.17-0704, (Released:2018-05-17)

被引用文献数

7

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Feline coronavirus (FCoV) is classified into two biotypes based on its pathogenicity in cats: a feline enteric coronavirus of low pathogenicity and a highly virulent feline infectious peritonitis virus. It has been suspected that FCoV alters its biotype via mutations in the viral genome. The S and 3c genes of FCoV have been considered the candidates for viral pathogenicity conversion. In the present study, FCoVs were analyzed for the frequency and location of mutations in the S and 3c genes from faecal samples of cats in an animal shelter and the faeces, effusions, and tissues of cats that were referred to veterinary hospitals. Our results indicated that approximately 95% FCoVs in faeces did not carry mutations in the two genes. However, 80% FCoVs in effusion samples exhibited mutations in the S and 3c genes with remainder displaying a mutation in the S or 3c gene. It was also suggested that mutational analysis of the 3c gene could be useful for studying the horizontal transmission of FCoVs in multi-cat environments.

著者

Takahiro USHIGUSA Yoshiyuki KOYAMA Tomoko ITO Kenichi WATANABE James K. CHAMBERS Aya HASEGAWA Kazuyuki UCHIDA Ryoji KANEGI Shingo HATOYA Toshio INABA Kikuya SUGIURA

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

pp.17-0466, (Released:2018-01-01)

被引用文献数

6

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By using a complex of DNA, polyethylenimine and chondroitin sulfate, the in vivo transfection of early secretory antigenic target-6 (ESAT-6) gene into tumor cells was found to cause significant suppression of the tumor growth. In order to apply the method in clinical cancer treatment in dogs and cats, mechanisms underlying the suppressive effects were investigated in a tumor-bearing mouse model. The transfection efficiency was only about 10%, but the transfection of ESAT-6 DNA nevertheless induced systemic immune responses against ESAT-6. By triple injection of ESAT-6 DNA at three day intervals, the tumor was significantly reduced and almost disappeared by 5 days after the start of treatment, and did not increase for more than 15 days after the final treatment. In the immunohistochemistry, a larger number of dendritic cells (DCs)/macrophages expressing ionized calcium-binding adapter molecule 1 and CD3+ T cells was observed in tumors treated with ESAT-6 DNA, and their population further increased significantly by day 5. Moreover, the amount of tumor necrosis factor, which is an apoptosis-inducing factor produced mainly by DCs/macrophages, was greater in the ESAT-6 DNA treated tumors than in controls, and increased with repeat of the treatment. These results indicate that in vivo transfection of ESAT-6 DNA into tumor cells elicits significant inhibition of tumor growth, by inducing potent activity of innate immunity mediated by DCs/macrophages, which may be followed by adaptive immunity against tumor associated antigens, which was elicited by the costimulation with ESAT-6 antigen.

著者

Aprilia MAHARANI Keisuke AOSHIMA Shinichi ONISHI Kevin Christian Montecillo GULAY Atsushi KOBAYASHI Takashi KIMURA

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

pp.17-0561, (Released:2018-01-01)

被引用文献数

15

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Canine hemangiosarcoma (HSA) is one of the most common mesenchymal tumors in dogs. Its high metastatic and growth rates are usually associated with poor prognosis. Neoplastic cells of HSA can show various levels of cellular atypia in the same mass and may consist of various populations at different differentiated stages. Up to present, however, there is no report analyzing their differentiation states by comparing cellular atypia with differentiation-related protein expressions. To evaluate whether cellular atypia can be used as a differentiation marker in HSA, we analyzed correlation between cellular atypia and intensities of CD31 and von Willebrand Factor (vWF) staining in HSA cases. We also compared cellular atypia and expression levels of CD31 and vWF in each growth patterns. Our results show that cellular atypia was negatively correlated to CD31 and vWF expression levels but no significant correlation was found between growth patterns and cellular atypia or CD31 and vWF expression levels. Our study suggests that cellular atypia is useful for identifying differentiation levels in HSA cases. This study also provides useful information to determine differentiation levels of cell populations within HSA based only on morphological analysis, which will aid further HSA research such as identifying undifferentiation markers of endothelial cells or finding undifferentiated cell population in tissue sections.

著者

Meina TEI Kazuyuki UCHIDA James K. CHAMBERS Ken-ichi WATANABE Takashi TAMAMOTO Koichi OHNO Hiroyuki NAKAYAMA

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

pp.17-0447, (Released:2017-12-04)

被引用文献数

5

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Amyloid A (AA) amyloidosis, a fatal systemic amyloid disease, occurs secondary to chronic inflammatory conditions in humans. Although persistently elevated serum amyloid A (SAA) levels are required for its pathogenesis, not all individuals with chronic inflammation necessarily develop AA amyloidosis. Furthermore, many diseases in cats are associated with the elevated production of SAA, whereas only a small number actually develop AA amyloidosis. We hypothesized that a genetic mutation in the SAA gene may strongly contribute to the pathogenesis of feline AA amyloidosis. In the present study, genomic DNA from four Japanese domestic cats (JDCs) with AA amyloidosis and from five without amyloidosis was analyzed using polymerase chain reaction (PCR) amplification and direct sequencing. We identified the novel variation combination of 45R-51A in the deduced amino acid sequences of four JDCs with amyloidosis and five without. However, there was no relationship between amino acid variations and the distribution of AA amyloid deposits, indicating that differences in SAA sequences do not contribute to the pathogenesis of AA amyloidosis. Immunohistochemical analysis using antisera against the three different parts of the feline SAA protein—i.e., the N-terminal, central, and C-terminal regions—revealed that feline AA contained the C-terminus, unlike human AA. These results indicate that the cleavage and degradation of the C-terminus are not essential for amyloid fibril formation in JDCs.

著者

Yasutsugu MIWA Asuka KUROSAWA Hiroyuki OGAWA Hiroyuki NAKAYAMA Hiroshi SASAI Nobuo SASAKI

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

vol.71, no.4, pp.397-402, 2009 (Released:2009-05-02)

参考文献数

20

被引用文献数

24 36

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The objective of this study was to collect epidemiological data on neoplasms in pet ferrets in Japan. A questionnaire to collect information was made available to Japanese veterinary practitioners through the web site of the Japanese Society of Exotic Pet Medicine. Completed questionnaires were returned from 29 practices, and 945 neoplasms met the criteria for inclusion in the study. Neoplasms were found in every organ system except the respiratory system; the endocrine (418; 44.2%), integumentary (196; 20.7%) and hemolymphatic (184; 19.5%) systems were most commonly affected. The most common tumor types were pancreatic islet cell tumor (211: 22.3%), adrenal gland tumor (207; 21.9%) and lymphoma (152; 16.1%). The age of the affected ferrets ranged from less than 3 months to more than 7 years of age. Tumor incidence was highest in ferrets between 4 and 6 years of age. No sex predilection was found. These results were similar to those recently published in North America. Most Japanese pet ferrets are imported from North America, and their husbandry including diets is similar to that in North America, which may explain the similar tendencies in the incidence of neoplasms in this study and those of findings in North America.

著者

筒井 敏彦 村尾 育子 河上 栄一 小笠 晃 Stabenfeldt George H.

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

日本獸醫學雜誌(The Japanese Journal of Veterinary Science) (ISSN:00215295)

巻号頁・発行日

vol.52, no.4, pp.801-806, 1990

被引用文献数

8

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繁殖季節における雄猫の androgen分泌状況を明らかにするため, 末梢血中 testosterone (T)の日内変動, 精巣静脈血と末梢血中における androgen量 [androstenedione (A), 5α-dihydrotestosterone (DHT), T]の関係について観察した. また精巣の組織学的観察によって造精機能についても検討した. 実験には自然採光下の猫舎内で飼育されている年齢2-3才, 体重3.5-4.0kgの雄猫9頭を用いた. その結果, 雄猫の日内における末梢血中T量は, 個体によって大きく変動していたが, 一定の傾向は認められず, episodicな分泌であった. 精巣静脈血中における androgenは個体によってかなりの差が認められたが, 左右の間ではほ等しかった. また3種 androgen量は, それぞれ精巣静脈血と末梢血の間で相関関係が認められた(A:P<0.01, DHT:P<0.05, T:P<0.01). 精巣の組織所見は, いずれの猫においても活発な精子形成が認められ, 各個体間において精細管径および各種精細胞数にも有意差は認められなかった.

著者

MAEDA Yousuke OHTSUKA Hiromichi TOMIOKA Michiko TANABE Taishi NAMBO Yasuo UEMATSU Haruki OIKAWA Masa-aki

出版者

JAPANESE SOCIETY OF VETERINARY SCIENCE

雑誌

Journal of Veterinary Medical Science (ISSN:09167250)

巻号頁・発行日

vol.74, no.5, pp.629-632, 2012

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<i>Escherichia coli</i>(<i>E. coli</i>) isolated from the uterus of a Thoroughbred mare with bacterial endometritis was used to evaluate the effect of progesterone (P₄) on the immune response of mares. Peripheral blood mononuclear cells (PBMCs) were collected from 10 nonpregnant clinically healthy adult mares (range, 4-12 years) during diestrus, four Thoroughbreds and six Hokkaido native horses. Cell proliferation and expression of cytokine mRNA, including interferon (IFN)-γ, tumor necrosis factor (TNF)-α and interleukin (IL)-10, of PBMCs stimulated with <i>E. coli</i> and P₄ were examined <i>in vitro</i>. P₄ was shown to have significantly inhibited <i>E. coli</i> induced proliferation and expression of IFN-γ in PBMCs. These results indicate that P₄ inhibits the immune response to <i>E. coli</i> in mares.