Development of sperm separation to improve the reproductive performance of cattle

• Project/Area Number: 15H04585
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Animal production science
• Research Institution: National Institute of Advanced Industrial Science and Technology
• Principal Investigator: YAMASHITA Kenichi 国立研究開発法人産業技術総合研究所, エレクトロニクス・製造領域, 研究グループ長 (90358250)
• Co-Investigator(Kenkyū-buntansha): 阪谷 美樹 国立研究開発法人農業・食品産業技術総合研究機構, 畜産研究部門, 上級研究員 (00355687) ; 山中 賢一 佐賀大学, 農学部, 准教授 (40572920)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Project Status: Completed (Fiscal Year 2018)
• Budget Amount: ¥15,730,000 (Direct Cost: ¥12,100,000、Indirect Cost: ¥3,630,000); Fiscal Year 2018: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2017: ¥4,680,000 (Direct Cost: ¥3,600,000、Indirect Cost: ¥1,080,000); Fiscal Year 2016: ¥4,680,000 (Direct Cost: ¥3,600,000、Indirect Cost: ¥1,080,000); Fiscal Year 2015: ¥5,460,000 (Direct Cost: ¥4,200,000、Indirect Cost: ¥1,260,000)
• Keywords: 家畜繁殖 / 不妊治療 / 人工授精 / 体外受精 / 受精卵移植 / 流体工学 / 家畜 / 繁殖 / マイクロ流体 / 相似則 / 畜産学 / マイクロ・ナノデバイス

Outline of Final Research Achievements

Our research focused on sperm manipulation to improve the reproductive performance of cattle. Our experiments were conducted based on preceeding studies on infertility treatment of humans by relying on the advantages of motile spermatozoa, that is, by being able to swim around and against the flow of solution, and considering such quality as an attribute of healthy and physiologically functional spermatozoa. We succeeded in collecting the number of spermatozoa that can be used for artificial insemination for the first time, and obtained good conception results in the field trial. In addition, the field trial clarifies the property of sperm advantageous to conception to be linked to the trajectory. Moreover, we studied the scientific evidences of good fertility by analyzing collected sperm and in vitro fertilization.

Academic Significance and Societal Importance of the Research Achievements

家畜の繁殖性改善は、畜産業の生産性向上による食糧供給の安定化とともに、地方の産業振興やバイオエコノミーとしての位置づけなど、幅広い意義を持つ。この研究では、牛の繁殖性の改善につながる精子の性状を、泳ぎの形で「見える化」するとともに、泳ぎの形ごとに分ける技術も開発した。ここで得られた知見は、繁殖用精液の改善の方向性を示すとともに、その精子の質的健全性から、体外受精などの成績改善につながるものと期待される。

Research Products

• [Journal Article] Live births from artificial insemination of microfluidic-sorted bovine spermatozoa characterized by trajectories correlated with fertility (2018)
  • Author(s): Maria Portia B. Nagata, Kenji Endo, Kazuko Ogata, Kenichi Yamanaka, Junki Egashira, Naoto Katafuchi, Tadayuki Yamanouchi, Hideo Matsuda, Yuki Goto, Miki Sakatani, Takuo Hojo, Hirofumi Nishizono, Kenji Yotsushima, Naoki Takenouchi, Yutaka Hashiyada, Kenichi Yamashita
  • Journal Title: Proceedings of the National Academy of Sciences of the United States of America Volume: 115 Issue: 14 Pages: 3087-3096
  • DOI: 10.1073/pnas.1717974115
  • Peer Reviewed / Open Access
• [Presentation] 家畜繁殖用精液の改良に向けた精子の性質分析と人工授精成績 (2019)
  • Author(s): 山下健一
  • Organizer: 産総研北海道センターワークショップ in 帯広
  • Invited
• [Presentation] 受胎性向上を目指した精子分離技術への流体操作の応用 (2018)
  • Author(s): 山下健一
  • Organizer: 第52回日本実験動物技術者協会総会
  • Invited
• [Presentation] 受胎率向上を目指した家畜繁殖用精液の改良技術 (2018)
  • Author(s): 山下健一
  • Organizer: 九州・沖縄 産業技術オープンイノベーションデー
  • Invited
• [Presentation] Effects of new sperm sorting method on bovine embryonic development in vitro (2017)
  • Author(s): Miki Sakatani, Takuo Hojo, Naoki Takenouchi, Maria Portia B. Nagata, Kenichi Yamashita
  • Organizer: WCRB(World congress of reproductive biology)
  • Int'l Joint Research
• [Remarks] 受胎に有利な精子を泳ぎ方で選んで捕集する技術
  • URL: http://www.aist.go.jp/aist_j/press_release/pr2018/pr20180320/pr20180320.html
• [Patent(Industrial Property Rights)] 運動性精子を分離する方法および装置 (2017)
  • Inventor(s): 山下 健一、永田 MariaPortia
  • Industrial Property Rights Holder: 国立研究開発法人産業技術総合研究所
  • Industrial Property Rights Type: 特許
  • Industrial Property Number: 2017-225102
  • Filing Date: 2017