- Animals: bovine
- Animal Production: livestock breeding
The utilization of in vitro fertilization has enabled the substantial improvement of genetics and productivity of beef and dairy cattle. In 2017, it was reported that, for the first time in history, a larger number of bovine embryos were produced in vitro and transferred worldwide rather than in vivo. However, the rate of transferable embryos produced in vitro ranges from 30–40%. The characterization of genes driving oocyte maturation and early embryonic development is imperative to improving bovine IVF. Transcriptomic data has indicated the bovine oocyte highly expresses agouti signaling protein (ASIP) mRNA. The role of ASIP in reproduction is currently unknown. The objective of this project is to elucidate the function of ASIP during oocyte maturation and early embryonic development in cattle which will be accomplished through the characterization of ASIP in the follicle, oocyte, and stages of early embryonic development. The possible effects of the reduction of endogenous ASIP and supplementation of exogenous ASIP on oocyte maturation and early embryonic development will be addressed. Identification of ASIP-mediated actions may contribute to the improvement of the in vitro production of bovine embryos. Also, cumulus cell ASIP expression may be utilized as a marker of oocyte competence. Results obtained from this project could be beneficial to both beef and dairy producers utilizing IVF by increasing the rate of transferable embryos obtained which will save both time and money. Outreach will include the presentation of data at several reproductive physiology conferences well attended by bovine embryologists, researchers, and veterinarians.
Project objectives from proposal:
- Determine the expression profile and spatial distribution of bovine ASIP mRNA and protein in bovine ovarian tissue, GV and MII oocytes, follicular cells, and early embryos
- Characterize the effect of exogenous ASIP supplementation on oocyte maturation and early embryogenesis in cattle
- Investigate the possible role(s) of bovine oocyte derived ASIP in cumulus cell expansion, oocyte maturation, and early embryonic development to determine if ASIP is an indicator of oocyte competence