Abstract #160

Section: IVF/IVP
Session: IVF/IVP
Format: Poster
Location: Rio Exhibit Hall B
# 160
N. C. Negota*1, L. P. Nethenzheni1,3, M. L. Mphaphathi3, D. M. Barry1, T. L. Nedambale2, 1Department of Animal Science, CEAAR, School of Agriculture, University of Venda, Thohoyandou, South Africa;, 2Department of Animal Science, Tshwane University of Technology, Pretoria, South Africa;, 3Agricultural Research Council, Germplasm Conservation & Reproductive Biotechnologies, Animal Production Institute, Irene, South Africa.

The in vitro culture media and assisted hatching techniques remain challenging obstacles to be utilised widely. Mechanical, chemical, enzymatic thinning, and laser-assisted techniques have been used previously but information is still lacking on its application in livestock. The aim of this study was to compare the effect of 2 in vitro culture media (Hamster F10 and TMC-199) and 4 (mechanical, chemical, enzymatic, and laser) assisted hatching techniques on blastocyst formation and hatching rate using murine embryos as a model. The C57/b and Balb/c breeds were raised until they reached maturity and bred naturally to produce F1 generation. The light in the breeding house was controlled at 14 h light and 10 h dark. Feed and water were provided ad libitum for the mice. Superovulation of females were stimulated using equine chorionic gonadotropin and human chorionic gonadotropin. The F1 generation was used for the collection of the 400 blastocysts and randomly allocated into 4 assisted hatching techniques. Blastocysts were paired into a group of 10 and replicated 4 times for each assisted hatching technique. The general linear model of SAS version 9.4 (SAS Institute Inc., Cary, NC, USA) was used to analyse the data. Assisted hatching techniques of laser, mechanical, enzymatic, and chemical yielded 46.9 ± 37.1, 51.1 ± 40.2, 39.1 ± 35.8, and 33.3 ± 4.5%, respectively, under in vitro culture of Hamster F10. The TCM-199, laser, mechanical, enzymatic, and chemical assisted hatching techniques yielded 56.3 ± 43.3, 52.6 ± 35.5, 49.2 ± 37.5, and 33.9 ± 35.5%, respectively, with a significant difference. There was no significant difference observed in assisted hatching techniques and Hamster F10 culture medium. However, the hatching rate of embryos for all techniques was higher when in vitro cultured in TCM than cultured in Hamster F10. Hatching rate of blastocysts increased from chemical, enzymatic, mechanical, and laser with response to Hamster F10 and TCM; thus, laser is a suitable assisted hatching technique with TCM-199.