Development of new follicle growth control technology for cattle based on vaginal administration

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K06400
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 42020:Veterinary medical science-related
• Research Institution: Tokyo University of Agriculture and Technology
• Principal Investigator: Endo Natsumi 東京農工大学, (連合)農学研究科(研究院), 准教授 (40726684)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: intravaginal / estrus synchronization

Outline of Final Research Achievements

At present dairy farms, there is an increasing need for estrus/ovulation induction methods by administration of prostaglandin F2α (PG), estradiol benzoate (EB), etc. as a countermeasure against the increase in ovarian disorders and decreased fertility in dairy cows. In this study, we focused on the vaginal route dosing method and considered that the endocrine environment that can effectively stimulate follicle development can be created by applying the latest sustained release technique that controls sustained release and elution pattern. .. When Shiba goat was used as a model animal for cattle in an experiment and the effect of vaginal administration of PG was compared with that of conventional intramuscular injection. It was found that a similar effect can be obtained by dividing the number of administrations into two or by administering the drug mixed with the sustained-release base and filled in the capsule.

Free Research Field

獣医臨床繁殖学

Academic Significance and Societal Importance of the Research Achievements

牛のモデル動物としてシバヤギを実験に供試し、PGの経腟投与効果を従来の筋肉注射と比較した結果、筋肉注射で用いた投与量と同量では黄体退行率が少ないものの、投与回数を2回に分けることで同等の黄体退行率が得られることが示された。さらに、次の実験では、EBを徐放基剤と混合してゼラチンカプセルに充填して経腟投与した結果、同量のEBを筋肉注射した場合に匹敵する血漿エストラジオール濃度および発情誘起効果が得られた。以上の結果から、経腟投与を基盤とした繁殖ホルモン剤の投与方法は、従来の筋肉注射に代わる新たな方法として、実用化できる可能性が示唆された。