In vitro maturation and fertilization, and subsequent development of buffalo (Bubalus bubalis) embryos: effects of oocyte quality and type of serum

Abstract

In Experiment 1, to determine the developmental potential of buffalo oocytes of different qualities, compact cumulus-oocyte complexes (COCs) with an unexpanded cumulus mass, and with homogeneous ooplasm were classified as Grade 1 (with > or =5 layers of cumulus cells) and Grade 2 less than 4 layers of cumulus cells). Grade-3 oocytes were either without cumulus cells or with expanded cumulus mass, and with irregular ooplasm. The oocytes were matured for 24 h at 38.5 degrees C, 5% CO2 in air in maturation medium (10% fetal bovine serum (FBS) in TCM-199 supplemented with 5 microg mL(-1) follicle stimulating hormone-P). The nuclear maturation and cleavage rates, and the proportion of cleaved embryos which developed to morula and blastocyst stage were in the order Grade 1>Grade 2>Grade 3 (P < 0.05). For Experiment 2, the maturation medium consisted of TCM-199 supplemented with one of the following sera at 10% concentration: (1) buffalo oestrus serum (BOS), (2) superovulated buffalo serum (SBS), (3) fetal bovine serum (FBS) and (4) steer serum (SS). After in vitro fertilization (IVF), the oocytes were co-cultured with buffalo oviductal epithelial cells in TCM-199 containing the respective sera at 10% concentration for the subsequent 9 days. The extent of cumulus expansion and nuclear maturation were not different among different groups. The cleavage rates were lower (P < 0.05) with FBS than with BOS, SBS and SS. The proportion of cleaved embryos which developed to blastocyst stage was higher (P < 0.05) with SBS than with BOS, FBS and SS.

Differences in developmental competence and gene expression profiles between buffalo (Bubalus bubalis) preimplantation embryos cultured in three different embryo culture media

“…This system is complex and associated blastocyst yield is very low. Sub-optimal laboratory culture conditions for media preparation have been documented by Chauhan et al (1998) for buffalo in vitro fertilized embryos. These authors reported that the quality of water and chemicals used in media preparation may adversely affect in vitro embryo development.…”

Developmental competence and expression pattern of bubaline (Bubalus bubalis) oocytes subjected to elevated temperatures during meiotic maturation in vitro

“…Simultaneously, the spermatozoa were processed by the method provided by Chauhan et al [13] and were taken from the same donor tested for IVF earlier. Briefly, two straws of frozen-thawed buffalo semen were washed twice with BO medium and the pellet obtained was resuspended in 0.5 ml of the capacitation-fertilization medium (BO).…”

Real-Time PCR Based Expression Study of Cyclin B Gene in Buffalo Cumulus Oocyte

“…The results for IVF in buffalo are very poor as compared to cattle because majority of IVF studies in buffalo use the protocols which are established for cattle (Yousaf and Chohan, 2003). The overall success rate of embryo production following IVF in buffalo is reported to be not more than 10-15 percent which is very low when compared to that of cattle (Chauhan et al, 1998;Nandi et al, 2001;Raghu et al, 2002). Nandi et al (2002) have reported approximately 80 percent of buffalo oocytes fail to reach the blastocyst stage and most of blastocysts are not capable of further development.…”