The ovarian follicle of ruminants: The path from conceptus to adult

Authors

Jennifer L. Juengel, AgResearch Invermay Agricultural CentreFollow
Robert A. Cushman, USDA, Agricultural Research ServiceFollow
Joëlle Dupont, Université de Tours
Stéphane Fabre, Institut National Polytechnique de Toulouse
Richard G. Lea, University of Nottingham, Faculty of Medicine and Health Sciences
Graeme B. Martin, The University of Western Australia
Francesca Mossa, Università degli Studi di Sassari
Janet L. Pitman, Victoria University of Wellington
Christopher A. Price, University of Montreal
Peter Smith, AgResearch Invermay Agricultural Centre

ORCID IDs

Jennifer L. Juengel https://orcid.org/0000-0002-2717-7311

Stéphane Fabre https://orcid.org/0000-0001-7350-9500

Richard G. Lea https://orcid.org/0000-0002-6793-3601

Date of this Version

8-1-2021

Document Type

Article

Citation

Reproduction, Fertility and Development, 2021, 33, 621–642

https://doi.org/10.1071/RD21086

Comments

Open Access CC BY-NC-ND

Abstract

This review resulted from an international workshop and presents a consensus view of critical advances over the past decade in our understanding of follicle function in ruminants. The major concepts covered include: (1) the value of major genes; (2) the dynamics of fetal ovarian development and its sensitivity to nutritional and environmental influences; (3) the concept of an ovarian follicle reserve, aligned with the rise of anti-Müllerian hormone as a controller of ovarian processes; (4) renewed recognition of the diverse and important roles of theca cells; (5) the importance of follicular fluid as a microenvironment that determines oocyte quality; (6) the 'adipokinome' as a key concept linking metabolic inputs with follicle development; and (7) the contribution of follicle development to the success of conception. These concepts are important because, in sheep and cattle, ovulation rate is tightly regulated and, as the primary determinant of litter size, it is a major component of reproductive efficiency and therefore productivity. Nowadays, reproductive efficiency is also a target for improving the 'methane efficiency' of livestock enterprises, increasing the need to understand the processes of ovarian development and folliculogenesis, while avoiding detrimental trade-offs as greater performance is sought.