Published online by Cambridge University Press: 27 March 2009
Oocyte recovery was conducted in 329 slaughtered sheep; from 3072 vesicular follicles ruptured, 1210 oocytes were obtained (av. 3·7 per sheep). After recovery or culture in various media, 801 oocytes were examined for developmental stages. In cattle follicular fluid, little evidence of resumption of meiosis was found. In sheep follicular fluid, meiosis was resumed in many oocytes, but was arrested at the pro-metaphase to metaphase-I stage. A high proportion of oocytes matured to metaphase-II when cultured in growth medium.