Transition of cell numbers in bovine preimplantation embryos: In vivo collected and In vitro produced embryos

• Published in: Journal of Reproduction and Development Vol. 54; no. 4; pp. 239 - 243
• Main Authors: Ushijima, H.(Chiba-ken. Ichihara Dairy Experimental Station (Japan)), Akiyama, K, Tajima, T
• Format: Journal Article
• Language: English
• Published: Japan THE SOCIETY FOR REPRODUCTION AND DEVELOPMENT 01.08.2008
• Subjects: ANIMAL EMBRYOS; Animals; Blastocyst - cytology; BOVIN; Bovine; CATTLE; Cattle - physiology; Cell Count; Cleavage division; Cleavage Stage, Ovum; DUPLICATION EMBRYONNAIRE; EMBRIONES ANIMALES; EMBRYO SPLITTING; Embryo, Mammalian; EMBRYON ANIMAL; Embryonic Development - physiology; FECONDATION IN VITRO; FECUNDACION IN VITRO; Female; Fertilization in Vitro - methods; GANADO BOVINO; IN VITRO FERTILIZATION; Oocyte Retrieval - methods; OPERACIONES QUIRURGICAS; OPERATION CHIRURGICALE; PARTICION DE EMBRIONES; Pregnancy; Preimplantation embryo; SUPEROVULACION; SUPEROVULATION; Superovulation - physiology; SURGICAL OPERATIONS; Total cell numbers
• ISSN: 0916-8818; 1348-4400
• DOI: 10.1262/jrd.19128

The total cell numbers (TCNs) of bovine embryos collected from superovulated donors (VIVO embryos) were counted at 0-9 d after ovulation to quantify the developmental process. Using numerical analysis of embryo development, we also compared the developmental process of VIVO embryos, in vitro-fertilized (IVF) embryos and nuclear transfer (NT) embryos obtained from enucleated oocytes and blastomere nuclei. The TCNs of embryos were measured using the air-dry method. Cleavage divisions (CD) of the embryos were obtained using logarithmic transformation of the TCN. The TCN of the VIVO embryos increased significantly (P0.001) with time. The relationship between the CD of the VIVO embryos at 0-9 d after ovulation and age in days was described by a linear equation with a high correlation (y0.05). The results suggest a delay in development at these developmental stages. The slopes of regression lines of the IVF and NT embryos were significantly (P0.001) smaller, indicating that quantification of the developmental process of VIVO embryos according to TCN and CD would be useful as criteria for numerical evaluation of the developmental process of bovine in vitro produced embryos.