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Supplementary Materials and methods Porcine oocyte collection and in vitro maturation Abattoir-derived porcine ovaries were transported to the laboratory within 2 h in a physiological saline containing penicillin G/streptomycin sulphate. Cumulus-oocyte complexes (COCs) were isolated from the follicles (3-6 mm in diameter) using a disposable syringe with a 20-gauge needle. Oocytes with a compact cumulus cells were used for in vitro maturation (IVM) in TCM-199 (ThermoFisher Scientific, Waltham, MA, USA) supplemented with 10 ng/mL EGF, 5 μg/mL insulin, 0.2 mM pyruvate, 0.6 mM cysteine, 10% porcine follicular fluid, 10 IU/mL of each eCG and hCG, and 25 μg/mL kanamycin. 20-30 germinal vesicle (GV) oocytes were cultured for 44-48 h to metaphase II stage in 100 μL TCM-199 covered with mineral oil at 38.5°C, 5% CO2, and then cultured for additional 48 h for postovulatory aging.