The covering of ovum at ovulation is __________.

At ovulation, the mammalian ovum (in the secondary oocyte stage) is released from the Graafian follicle.

It is surrounded by two main coverings:
1. Zona pellucida: An inner, non-cellular glycoprotein layer secreted by the oocyte.
2. Corona radiata: An outer, cellular layer formed by the follicular cells (granulosa cells).