Factors affecting in vitro maturation of alpaca (Lama paco) oocytes

Abstract The present study utilized a 2 × 2 × 2 factorial design examining age (old vs. young), follicle size (≥2 mm vs. 11 years old). Oocytes were classified as morphologically normal oocytes (MNO) and deemed suitable for incubation if ≥3 compact layers of cumulus cells and a homogeneous, evenly granulated cytoplasm were observed. Oocytes from each group of follicle sizes were incubated separately and halves of each group were randomly divided and incubated 24 h in chemically defined maturation media with or without 10% FBS. Maturation was defined as the visualization of a polar body at the end of the incubation period. Overall, a greater proportion of MNO were collected from follicles ≥2 mm than that obtained from smaller follicles, 55% (136/247) vs. 29.6% (162/547), respectively ( P P P