Factors that influence sperm capacitation in vitro and their effects on in vitro fertilization of equine oocytes

• Grant number: 24/08969-5
• Support Opportunities: Regular Research Grants
• Start date: June 01, 2025
• End date: May 31, 2027
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Reproduction
• Principal Investigator: Frederico Ozanam Papa
• Grantee: Frederico Ozanam Papa
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil
• Associated researchers: Ana Caroline Silva Soares ; Gabriel Augusto Monteiro ; Raquel Zaneti Puelker

Abstract

The use of biotechnologies in equine reproduction has advanced exponentially, driven by thedemand for genetic improvement of animals with high zootechnical value. Among thesetechnologies, in vitro fertilization (IVF) in horses remains challenging, with consistently lowsuccess rates reported over the past decades. This limited performance is directly associatedwith the peculiarities of equine spermatozoa in undergoing in vitro capacitation, especiallyfollowing cryopreservation. In this context, the present study was structured into threeexperiments with the following objectives: (1) to standardize in vitro sperm capacitationparameters using thawed semen, employing computer-assisted analysis and flow cytometry; (2)to evaluate the impact of cholesterol incorporation prior to freezing on post-thaw spermviability, in vitro capacitation, and subsequent in vitro embryo production; and (3) to investigatethe efficiency of conventional IVF techniques in equine species by analyzing the cleavage ratesof the resulting zygotes. (AU)