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Registros recuperados: 77 | |
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KAWASHIMA, Chiho; KANEKO, Etsushi; AMAYA MONTOYA, Carlos; MATSUI, Motozumi; YAMAGISHI, Norio; MATSUNAGA, Nobuyoshi; ISHII, Mitsuo; KIDA, Katsuya; MIYAKE, Yoichi; MIYAMOTO, Akio; 川島, 千帆; 松井, 基純; 石井, 三都夫; 木田, 克弥; 三宅, 陽一; 宮本, 明夫. |
The aim of this study was to investigate the relationship between the first ovulation within 3 weeks postpartum and subsequent ovarian cycles and fertility in high producing dairy cattle in Hokkaido, Japan. In Experiment 1, 110 cows (44 primiparous and 66 multiparous) were used to determine the effects of the first ovulation within 3 weeks postpartum on subsequent ovarian cycles. Milk samples were collected twice weekly from 7 to 100 days postpartum. The first ovulation was identified by an increase in milk progesterone (P4) to more than 1 ng/ml within 3 weeks postpartum. The numbers of cows showing ovulation and anovulation within 3 weeks postpartum were 31 (70.5%) and 13 (29.5%) in the primiparous cows and 35 (53.0%) and 31 (47.0%) in the multiparous... |
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Palavras-chave: Dairy cow; First ovulation; Postpartum; Resumption of ovarian cycle. |
Ano: 2006 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/916 |
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Kawashima, Chiho; Fukihara, Saori; Maeda, Mayumi; Kaneko, Etsushi; Montoya, Carlos Amaya; Matsui, Motozumi; Shimizu, Takashi; Matsunaga, Nobuyoshi; Kida, Katsuya; Miyake, Yoichi; Schams, Dieter; Miyamoto, Akio; 川島, 千帆; 松井, 基純; 清水, 隆; 木田, 克弥; 三宅, 陽一; 宮本, 明夫. |
Recent studies suggest that IGF-I is a crucial regulatory factor in follicular growth during early post-partum period. The aim of the present study was to determine in detail the changing profiles of metabolic and reproductive hormones in relation to ovulation of the dominant follicle (DF) of the first follicular wave post-partum in high-producing dairy cows. Plasma concentrations of related hormones in 22 multiparous Holstein cows were measured from 4 weeks pre-partum to 3 weeks post-partum, and the development of DF was observed with colour Doppler ultrasound. Thirteen cows showed ovulation by 15.2 days post-partum. Anovulatory cows showed higher GH and lower IGF-I levels than those in ovulatory cows during the peri-partum period. Each DF developed... |
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Palavras-chave: GROWTH-FACTOR-I; COMPETITIVE ENZYME-IMMUNOASSAY; ENERGY-BALANCE; OVARIAN ACTIVITY; STIMULATING-HORMONE; ESTRADIOL PRODUCTION; BODY CONDITION; MESSENGER-RNA; HOLSTEIN COWS; IGF-I. |
Ano: 2007 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/1658 |
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LEE, Hsu-Hsun; KIDA, Katsuya; MIURA, Ryotaro; INOKUMA, Hisashi; MIYAMOTO, Akio; KAWASHIMA, Chiho; HANEDA, Shingo; MIYAKE, Yoh-Ichi; MATSUI, Motozumi; 猪熊, 壽; 宮本, 明夫; 川島, 千帆; 羽田, 真悟; 松井, 基純. |
In peripartum dairy cows, insulin resistance (IR) increases to adjust the direction of energy to lactation after calving. To investigate the effect of prepartum IR on postpartum reproductive performance, the insulin tolerance test (ITT) was applied to 15 cows at 3 weeks (Pre21) and 10 days (Pre10) before the predicted calving date. Blood glucose area under the curve (AUCglu) within 120 min after administration of 0.05 IU/kg-BW insulin was calculated. The occurrence of first ovulation, days to first artificial insemination (AI) and first AI conception rate were recorded. Nutritional status postpartum was evaluated by blood chemical analysis. Based on AUCglu changes from Pre21 to Pre10, cows were classified into either the AUC-up group (AUCglu increase, n=5)... |
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Palavras-chave: Dairy cows; Glucose metabolism; Insulin tolerance test; Reproductive performance; Transition period. |
Ano: 2012 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4129 |
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KAWASAKI, Yurie; AOKI, Yuka; MAGATA, Fumie; MIYAMOTO, Akio; KAWASHIMA, Chiho; HOJO, Takuo; OKUDA, Kiyoshi; SHIRASUNA, Koumei; SHIMIZU, Takashi; 宮本, 明夫; 清水, 隆. |
The present study aimed to assess the effect of polymorphisms in the tumor necrosis factor α (TNF-α) promoter (A/A, A/G and G/G) and exons (T/T, T/C and C/C) on immune function and reproductive performance in dairy cows. The occurrence of the first postpartum ovulation within 3 weeks in the cows with the TNF-α promoter A/G and G/G genotypes was higher than in the A/A group. Among the different TNF-α exon genotypes, the occurrence of early first postpartum ovulation was higher in the T/C and C/C genotype groups than in the T/T group. Single nucleotide polymorphisms (SNPs) in the TNF-α gene did not affect the rate of artificial insemination (AI) or duration from parturition to next conception (days open). The apoptosis rate of polymorphonuclear leukocytes... |
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Palavras-chave: Cattle; Immune function; Polymorphism; Reproductive performance; Tumor necrosis factor α (TNF-α). |
Ano: 2014 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3934 |
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HAYASHI, Ken-Go; MATSUI, Motozumi; ACOSTA, Tomas J.; KIDA, Katsuya; MIYAMOTO, Akio; 松井, 基純; 木田, 克弥; 宮本, 明夫. |
Luteinizing hormone (LH) surge and follicle rupture act as trigger to start corpus luteum (CL) formation. Thus, we aimed to investigate whether a dominant follicle that has not been exposed to an LH surge can become a functional CL. For this purpose, follicular fluid from the dominant follicles (DF) of cows was aspirated before or after a GnRH-induced LH surge, and subsequent CL formation was observed. Holstein cows were divided into four groups as follows: Luteal phase, a DF was aspirated 7 days after GnRH injection; Pre-LH surge, a DF was aspirated 42 h after PGF2α injection during the mid luteal phase; Post-LH surge, a DF was aspirated 24 h after GnRH injection following PGF2α; and Intact follicle, ovulation was induced by GnRH injection after PGF2α.... |
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Palavras-chave: Corpus luteum formation; Cow; Follicle aspiration; LH surge. |
Ano: 2006 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2982 |
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ACOSTA, Tomas J.; HAYASHI, Ken-Go; MATSUI, Motozumi; MIYAMOTO, Akio; 松井, 基純; 宮本, 明夫. |
Increase in the blood supply to individual follicles appears to be associated with follicular growth rates and the ability to become the dominant follicle, while reduced thecal vascularity appears to be closely associated with follicular atresia. Therefore, this study aimed to determine the real-time changes in the vascularity of the follicle wall during the first follicular wave in cycling Holstein cows. Normally cycling and lactating cows (n=5) were examined by transrectal color Doppler ultrasonography (the sensitivity for velocity: > 2 mm/sec) to determine the changes in the vasculature of the follicle wall (presence or absence of blood flow) and the diameter of follicles. A new follicular wave and ovulation were induced by GnRH injection at 48 h... |
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Palavras-chave: Blood flow; Follicular wave; Selection; Deviation; Cow. |
Ano: 2005 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2979 |
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Ozawa, Takahiro; Acosta, Tomas J.; Nakamura, Tadashi; Miyamoto, Akio; 中村, 正; 宮本, 明夫. |
The presence of gonadotropin-releasing hormone (GnRH)-like protein has been previously demonstrated in the bovine follicle. This GnRH-like protein was purified and concluded to be histone H2A. However, neither GnRH peptide nor specific GnRH-immunoreactivity (GnRH-IR) has been demonstrated in the bovine follicle so far. Thus, this study focused on the detection of specific GnRH-IR using the second-antibody enzyme immunoassay in isolated bovine mature follicles, and on an examination of the direct effect of luteinizing hormone (LH), endothelin-1 (ET-1), and cytokines on the GnRH-IR using an in vitro microdialysis system (MDS). We further examined a cross-reactivity of the GnRH antibody with bovine histone H2A. GnRH-IR was detected in microdialyzed perfusate... |
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Palavras-chave: GnRH; Immunoreactivity; Microdialysis; Follicle; Cow. |
Ano: 2000 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2970 |
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HAYASHI, Ken-Go; BERISHA, Bajram; MATSUI, Motozumi; SCHAMS, Dieter; MIYAMOTO, Akio; 松井, 基純; 宮本, 明夫. |
Recent findings indicate that the changing profile of angiopoietins (ANPT) and their receptor Tie2 are closely associated with development and regression of the vascular network in the cyclic ovary. We previously reported that mRNA expression for the ANPT-Tie system in theca interna changes during bovine follicular development and atresia, and both ANPTs affect steroidogenesis in the preovulatory follicle. The aim of this study was to investigate mRNA expression for ANPT1, ANPT-2 and Tie2 in granulosa cells (GC) during follicular development in the cow. Bovine follicles were classified according to the estradiol-17β (E2) concentration in follicular fluid (FF) as follows: (1) E2<0.5, (2) 0.5<E2<5, (3) 5<E2<20, (4) 20<E2<180 and (5)... |
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Palavras-chave: Follicular development; Angiopoietin-Tie system; Granulosa cell; Cow. |
Ano: 2004 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2975 |
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ISHII, Mitsuo; KOBAYASHI, Syuichi; ACOSTA, Tomas J.; MIKI, Wataru; YAMANOI, Takahiro; MATSUI, Motozumi; MIYAKE, Yoh-Ichi; MIYAMOTO, Akio; 石井, 三都夫; 松井, 基純; 三宅, 陽一; 宮本, 明夫. |
The aim of this study was to clarify the relationship between circulating oxytocin (OT) and PGF2α metabolite (PGFM) in mares at the third stage of labor and placental expulsion time in order to investigate a cause of retained placenta of which the incidence increase in a heavy draft mare. Blood was sampled every 5 min from foaling to expulsion of the placenta in 18 heavy draft mares to evaluate circulating OT and PGFM. The relationships between OT and PGFM concentration and recorded placental expulsion times were investigated. The results were as follows (1) The highest level of OT concentration was observed close to foaling in 15 mares. (2) The OT concentrations close to foaling were variable with a large difference from the lowest concentration, 22.1... |
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Palavras-chave: Heavy draft mare; Oxytocin; 15-keto-dihydro prostaglandin F2α (PGFM); Placental expulsion. |
Ano: 2008 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3089 |
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SHIMIZU, Takashi; JAYAWARDANA, Barana C.; TETSUKA, Masafumi; MIYAMOTO, Akio; 清水, 隆; 手塚, 雅文; 宮本, 明夫. |
Vascular endothelial growth factor (VEGF) isoforms (VEGF 120 and VEGF 164) secreted by granulosa cells are involved in thecal angiogenesis during follicular development in the bovine ovary. However, whether the transcript of the VEGF120 and VEGF164 isoforms differs during follicular development in the ovary is still unknown. We first examined the gene expression of VEGF120, VEGF164, fms-like tyrosine kinase (Flt-1), and fetal liver kinase (Flk-1) in the granulosa cells (GCs) and theca cells (TCs) of pre-selection and post-selection follicles (PRF and POF respectively) from the bovine ovary. Then we examined the effects of FSH and estradiol (E2) on these factors in cultured bovine GCs. Messenger RNA (mRNA) expression was quantified using real-time PCR... |
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Palavras-chave: Estradiol; Fetal liver kinase (Flk-1); Fms-like tyrosine kinase (Flt-1); Follicle-stimulating hormone (FSH); Granulosa cell; Vascular Endothelial Growth factor (VEGF). |
Ano: 2007 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4057 |
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Fukui, Yutaka; Yamamura, Kunio; Matsunaga, Nobuyoshi; Miyamoto, Akio; 福井, 豊; 宮本, 明夫. |
The present study aimed to examine the possibility that bovine somatotropin (BST) treatment after artificial insemination (AI) may improve the fertility by the stimulation of corpus luteum (CL) function in seasonally anestrous ewes. The experiment was conducted at the Tawa Field Station, Shibecha-cho in Hokkaido, Japan, during the non-breeding season (May, 1995). Eighty-nine mature (2 to 3 years old) Suffolk and Suffolk-crossed ewes were treated with controlled internal drug release devices containing 0.3 g progesterone (CIDR-G) for 12 days. Ewes were injected intramuscularly with 500 IU PMSG the day before CIDR removal. Eighty-seven ewes were assigned to an insemination of frozen semen on a fixed-time basis (42 to 50 h) after removal of CIDR. On the 11th... |
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Palavras-chave: Bovine somatotropin; Artificial insemination; Progesterone; Conception rate; Ewes. |
Ano: 2000 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2971 |
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Watanabe, Sho; Shirasuna, Koumei; Matsui, Motozumi; Yamamoto, Dai; Berisha, Bajram; Schams, Dieter; Miyamoto, Akio; 白砂, 孔明; 松井, 基純; 宮本, 明夫. |
Endothelin-1 (ET-1) is a luteolytic mediator in the bovine corpus luteum (CL), and its action appears to be via endothelin type A receptor (ETR-A). Thus, the aim of the present study was to determine the effect of ETR-A antagonist on PGF(2)alpha-induced luteolysis in the cow. Cows on days 1012 of the estrous cycle were subjected to five intraluteal injections of the ETR-A antagonist LU 135252 in saline or only saline at -0.5, 2, 4, 6, and 8 h after PGF(2)alpha administration (=0 h). Serial luteal biopsies were conducted to determine the expression of mRNA in the luteal tissue. There were no significant differences in the decrease in plasma progesterone (P) concentrations and the mRNA expressions of steroidogenic acute regulatory protein and 3... |
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Palavras-chave: Apoptosis; Blood flow; Corpus luteum; Cow; Endothelin-1. |
Ano: 2006 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/922 |
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MAGATA, Fumie; ISHIDA, Yoshikazu; MIYAMOTO, Akio; FURUOKA, Hidefumi; INOKUMA, Hisashi; SHIMIZU, Takashi; 宮本, 明夫; 古岡, 秀文; 猪熊, 壽; 清水, 隆. |
We investigated the concentration of the bacterial endotoxin lipopolysaccharide (LPS) in the blood, ovarian follicular fluid and uterine fluid of a clinical case of bovine metritis. A 2-year-old lactating Holstein cow exhibited continuous fever >39.5°C for more than 2 weeks after normal calving. The cow produced a fetid, watery, red-brown uterine discharge from the vagina and was diagnosed with metritis. The LPS concentrations in plasma and uterine fluid were 0.94 and 6.34 endotoxin units (EU)/ml, respectively. One of seven follicles showed an extremely high level of LPS (12.40 EU/ml) compared to the other follicles (0.62–0.97 EU/ml). These results might suggest the presence of high concentration of LPS in follicles in cows with postpartum metritis. |
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Palavras-chave: Dairy cow; Follicle; Lipopolysaccharide; Metritis. |
Ano: 2015 |
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/4043 |
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Registros recuperados: 77 | |
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