Physiological and molecular aspects of ovarian follicular developmental competence in sows

Abstract

Chapter 1 General IntroductionChapter 2 Follicular development of sows at weaning in relation to estimated breeding value for within-litter variation in piglet birth weight Chapter 3 In ovaries with high or low variation in follicle size, granulosa cells of antral follicles exhibit distinct size-related processes Chapter 4 Follicular fluid steroid profile in sows: relation to follicle size and 77 oocyte quality Chapter 5 Steroid profile of porcine follicular fluid and blood serum: relation with follicular development Chapter 6 Consequences of negative energy balance on follicular development and oocyte quality in primiparous sows Chapter 7 Influence of the metabolic state during lactation on milk production in modern sows Chapter 8 General Discussion Appendices Summary of main findings Acknowledgements About the author Curriculum vitae List of publications 208 Education statement 209 General IntroductionGeneral Introduction 9 Research gapsTo conclude, reproductive problems in sows, such as the previously described trend towards lower piglet birth weights and associated pre-weaning mortality in highly prolific sows, may originate (at least partly) from impairments in the antral follicle pool from which follicles are selected to become ovulatory follicles, potentially giving rise to the next litter. The underlying processes, which determine, and influence follicle developmental competence remain poorly understood. Although previous studies have attempted to identify physiological characteristics of follicular developmental competence, these studies had variable outcomes. The main physiological characteristics that were studied are antral follicle size, where larger antral follicles either might yield better quality oocytes with improved blastocyst formation and implantation rates (