In vitro maturation and fertilization, and subsequent development of buffalo (Bubalus bubalis) embryos: effects of oocyte quality and type of serum.
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.
Chauhan
M S
MS
Embryo Biotechnology Centre, National Dairy Research Institute, Karnal, India.
Singla
S K
SK
Palta
P
P
Manik
R S
RS
Madan
M L
ML
D000818:Animals; D001769:Blood; D002020:Buffaloes / Q000196:embryology* / Q000502:physiology; D003470:Culture Media; D046508:Culture Techniques; D005307:Fertilization in Vitro / Q000379:methods; D009865:Oocytes / Q000254:growth & development* / Q000502:physiology
D003470:Culture Media