Version 1
: Received: 21 October 2020 / Approved: 22 October 2020 / Online: 22 October 2020 (09:49:26 CEST)
Version 2
: Received: 17 November 2020 / Approved: 17 November 2020 / Online: 17 November 2020 (12:41:51 CET)
Aguila, L.; Treulen, F.; Therrien, J.; Felmer, R.; Valdivia, M.; Smith, L.C. Oocyte Selection for In Vitro Embryo Production in Bovine Species: Noninvasive Approaches for New Challenges of Oocyte Competence. Animals2020, 10, 2196.
Aguila, L.; Treulen, F.; Therrien, J.; Felmer, R.; Valdivia, M.; Smith, L.C. Oocyte Selection for In Vitro Embryo Production in Bovine Species: Noninvasive Approaches for New Challenges of Oocyte Competence. Animals 2020, 10, 2196.
Aguila, L.; Treulen, F.; Therrien, J.; Felmer, R.; Valdivia, M.; Smith, L.C. Oocyte Selection for In Vitro Embryo Production in Bovine Species: Noninvasive Approaches for New Challenges of Oocyte Competence. Animals2020, 10, 2196.
Aguila, L.; Treulen, F.; Therrien, J.; Felmer, R.; Valdivia, M.; Smith, L.C. Oocyte Selection for In Vitro Embryo Production in Bovine Species: Noninvasive Approaches for New Challenges of Oocyte Competence. Animals 2020, 10, 2196.
Abstract
The efficiency of producing embryos using in vitro technologies in livestock species rarely exceeds the 30 to 40% threshold, indicating that the proportion of oocytes that fail to develop after in vitro fertilization and culture is considerably large. Considering that the intrinsic quality of the oocyte is one of the main factors affecting blastocyst yield, the precise identification of non-invasive cellular or molecular markers that predict oocyte competence is of major interest to research and practical applications. The aim of this review was to explore the current literature on different non-invasive markers associated with oocyte quality in the bovine model. Apart from some controversial findings, the presence of cycle-related structures in ovaries, a follicle size between 6 and 10 mm, large number of surrounding cumulus cells, slightly expanded investment without dark areas, large oocyte diameter (>120 microns), dark cytoplasm, and the presence of a round and smooth first polar body have been associated to better competence. In addition, the combination of oocyte and zygote selection by BCB test and spindle imaging have the potential to further optimize the identification of oocytes with better developmental competence for in vitro-derived technologies in livestock species.
Keywords
oocyte competence; livestock production; assisted reproductive technology; embryo development; micromanipulation; in vitro production
Subject
Biology and Life Sciences, Anatomy and Physiology
Copyright:
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Received:
17 November 2020
Commenter:
Luis Águila
Commenter's Conflict of Interests:
Author
Comment: We have done all the modifications suggested by the reviewers. The major changes in the new version are as follows: - Title as changed - A new section of non-invasive molecular approaches - We have included 2 representative images - We have included 2 tables.
Commenter: Luis Águila
Commenter's Conflict of Interests: Author
- Title as changed
- A new section of non-invasive molecular approaches
- We have included 2 representative images
- We have included 2 tables.