An investigation into the equine peri-conception period: utilising emerging biotechnologies to investigate the mechanisms of reproduction and early pregnancy in the mare

The advancement of technology has paved the way for the expansion of knowledge, especially in the context of equine reproduction. With many aspects of the mares biological reproductive pathways remaining undefined, emerging biotechnologies have provided novel avenues to explore previously unanswered questions. The unique challenges posed by equine reproductive research, have prompted the utilisation of new and accessible biotechnologies to help unravel the mysteries in this field. This thesis encompasses three main objectives: (1) utilising cutting-edge mass spectrometry to characterise the lipidomic components of the equine peri-conception period, including follicular fluid and early embryonic secretome; (2) establishing and characterising an oviductal organoid model to advance future research; and (3) integrating lipidomic data, organoid technology, and in vitro experimentation to gain a comprehensive understanding of mare reproductive function. The research approach focused on harnessing emerging biotechnologies to investigate potential biomarkers of early equine fertilisation, enhancing our understanding of early pregnancy and the peri-conception period. The study first employed state-of-the-art mass spectrometry to profile lipidomic components of the equine peri-conception period, revealing distinct lipid profiles in embryo-conditioned media. Subsequent establishment and characterisation of oviductal organoids across various species facilitated insights into oviductal physiology, including the observation of actively dividing cells and functional cilia. Lastly, the integration of lipidomic data and organoid technology pinpointed the role of Phospholipid Platelet-activating factor (PAF) in mare reproductive physiology. PAF's presence in equine follicular fluid and its potential role in embryo migration were explored, shedding light on its significance during the peri-conception period. These studies collectively provide valuable insights into equine physiology, embryo metabolism, and mare reproductive pathways. The interdisciplinary approach underscores the importance of employing cutting-edge biotechnologies to tackle intricate reproductive phenomena, ultimately advancing our understanding of equine reproduction and suggesting new avenues for future research.