Energy substrate requirement for in vitro maturation of oocytes from unstimulated adult rhesus monkeys

The energy substrates lactate, pyruvate, and glucose were evaluated for supporting in vitro cytoplasmic maturation of rhesus monkey oocytes. A total of 321 cumulus–oocyte complexes (COCs) aspirated from ≥ 1000 μm diameter follicles of unstimulated adult monkeys were matured in one of six media with various individual or combinations of energy substrates: (1) mCMRL‐1066 (control); (2) HECM‐10 (containing 4.5 mM lactate); (3) HECM‐10+0.2 mM pyruvate; (4) HECM‐10 + 5.0 mM glucose; (5) HECM‐10+ 0.2 mM pyruvate + 5.0 mM glucose; and (6) HECM‐10 minus lactate + 5.0 mM glucose. All media contained gonadotropins, oestradiol, and progesterone. Following maturation, all mature oocytes were subjected to the same in vitro fertilization and embryo culture procedures. Oocytes matured in control medium or in treatment groups 4 and 6 had the best morulae+ blastocysts developmental responses (35, 36, and 32%, respectively, P