After collection, COC were placed
into 2 mL cryovials (approximately 50 to 100 COC per
cryovial) containing maturation medium and shipped
overnight, in a portable incubator set at 39 C, to the
laboratory in Gainesville, FL, USA. Additional Holstein COC
were collected from locally obtained ovaries (Central
Packing Co., Center Hill, FL, USA) and matured as described
[14]. Regardless of collection procedure, all COC were
allowed to mature for 21 to 24 hours.