Consulta: creatorFacets:"KANEKO, Etsushi"
Registros recuperados: 4
Data/hora: 01/06/2024 02:53:36

Changes in Plasma Metabolic Hormone Concentrations During the Ovarian Cycles of Japanese Black and Holstein Cattle
Provedor de dados: 19
Autores: KAWASHIMA, Chiho; KIDA, Katsuya; HAYASHI, Ken-Go; AMAYA MONTOYA, Carlos; KANEKO, Etsushi; MATSUNAGA, Nobuyoshi; SHIMIZU, Takashi; MATSUI, Motozumi; MIYAKE, Yoh-Ichi; SCHAMS, Dieter; MIYAMOTO, Akio; 川島, 千帆; 木田, 克弥; 清水, 隆; 松井, 基純; 三宅, 陽一; 宮本, 明夫.
The aim of the present study was to investigate the changing profiles of plasma metabolic hormones during the ovarian cycles of beef and dairy cattle. We used 16 non-pregnant, non-lactating Japanese Black beef cattle (6 heifers and 10 cows; parity=2.3 ± 0.8) and 12 multiparous Holstein dairy cows (parity=3.0 ± 0.3). Blood samples for hormonal analysis (growth hormone, GH; insulin-like growth factor-I, IGF-1; insulin; and progesterone, P4) were obtained twice weekly for 40 days before artificial insemination for Japanese Black cattle and from 50 to 100 days postpartum for Holstein cows. Luteal phases were considered normal if the P4 concentrations for at least 3 time points over the course of 7 days remained above 1 ng/ml and at least 2 of the time points...
Palavras-chave: Cattle; Insulin-like growth factor-I; Ovarian cycle; Progesterone.
Ano: 2007
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2984

Relationship between the First Ovulation within Three Weeks Postpartum and Subsequent Ovarian Cycles and Fertility in High Producing Dairy Cows
Provedor de dados: 19
Autores: 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...
Palavras-chave: Dairy cow; First ovulation; Postpartum; Resumption of ovarian cycle.
Ano: 2006
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/916

A Potential Use of Color Ultrasound as a Tool for Reproductive Management: New Observations Using Color Ultrasound Scanning that were not Possible with Imaging Only in Black and White
Provedor de dados: 19
Autores: MIYAMOTO, Akio; SHIRASUNA, Koumei; HAYASHI, Ken-Go; KAMADA, Daichi; KAWASHIMA, Chiho; KANEKO, Etsushi; ACOSTA, Tomas J.; MATSUI, Motozumi; 宮本, 明夫; 白砂, 孔明; 川島, 千帆; 松井, 基純.
Ultrasonography (US) has been applied to the ovary and the uterus of domestic animals from the late 1980s, and established in 1990s as a practical tool for animal production. US made it possible to detect pregnancy at a very early stage and, most importantly, to observe the real-time dynamics of follicular development and hence the discovery of follicular waves. This has greatly contributed to our understanding of ovarian physiology and helped us to develop several "pin-point" protocols for hormonal treatment. While US may not seem to fit preconceived ideas of a "green" technology, it does not contravene environmental priorities, and it is non-invasive ("ethical") and non-hormonal ("clean"). Using the US technology that is now commercially available at a...
Palavras-chave: Color Doppler ultrasound; Blood flow; Ovary; Reproduction; Cow.
Ano: 2006
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/2983

Exposure of C57BL/6J Male Mice to an Electric Field Improves Copulation Rates with Superovulated Females
Provedor de dados: 19
Autores: HORI, Takuya; YAMSAARD, Thicomeporn; UETA, Yoshiko Yanagimoto; HARAKAWA, Shinji; KANEKO, Etsushi; MIYAMOTO, Akio; XUAN, Xuenan; TOYODA, Yutaka; SUZUKI, Hiroshi; 宮本, 明夫; 玄, 学南; 鈴木, 宏志.
It is well-known that there are considerable strain differences in the relative copulation rates between male and superovulated female mice. In particular, the C57BL/6J strain of mice has a lower rate of successful copulation. We examined the effect of exposure to an electric field on sexual behavior in C57BL/6J male mice. When C57BL/6J males were exposed to a 50 Hz, 45 kV/m electric field for 30 min per day for 11 days and placed in a cage with a superovulated female of the same strain, the successful copulation rates of males was significantly improved compared with unexposed males (P&lt;0.05). These results suggest that the exposure of C57BL/6J male mice to an electric field improves their sub-fertility activity in mating with superovulated females.
Palavras-chave: Mice; Male; Electric field; Copulation; Superovulation; Sexual behavior.
Ano: 2005
URL: http://ir.obihiro.ac.jp/dspace/handle/10322/3021