Development of buffalo embryo derived from ICSI: effects of various somatic-cell co-culture

Context Somatic-cell co-culture of intracytoplasmic sperm injection (ICSI) buffalo embryos has not been reported earlier.Aim This study aimed to determine the effects of buffalo oviductal epithelial-cell, granulosa-cell, and cumulus-cell co-culture on in vitro culture of early embryo development as ICSI and post-activation.Methods Selected oocyte–cumulus complexes were cultured for 19–20h in 50-μL drop of tissue culture medium (TCM199+10% buffalo follicular fluid, hCG 50IU/mL, 0.02% arbitrary units (AU)/mL follicle-stimulating hormone and 1μg/mL estradiol-17βE2). Oocytes reaching Metaphase II were subjected to ICSI with immobilised spermatozoa. All ICSI oocytes were activated with calcium ionophore for 5min, followed by cycloheximide for 5h. The embryos at 6–8-cell stages were co-cultured.Key results The morula, blastocyst, and hatched blastocyst rates when co-cultured with oviductal epithelial cells were 68.18%, 48.18%, and 30.00% respectively. The morula, blastocyst, and hatched blastocyst rates when co-cultured with cumulus cells were 51.49%, 34.33%, and 16.42% respectively. The morula, blastocyst, and hatched blastocyst rates when co-cultured with granulosa cells were 52.14%, 32.48%, and 13.68% respectively.Conclusions In vitro maturation buffalo oocytes can be fertilised in vitro with ICSI and co-cultured with different types of cells. Oviductal epithelial cell co-culture was shown to be superior in supporting in vitro embryo development in this study.Implications The oviductal epithelial cells are easy to prepare and may be used for co-culture to increase the efficiency of in vitro production of buffalo embryos.