[Synthetic medium for gamete survival and maturation and for culture of fertilized eggs]

A defined medium more similar to female genital tract fluids than to blood serum is tested on bull sperm survival, calf oocyte maturation and cleavage of Rabbit and Cow fertilized eggs: -- after incubation for 24 hrs. at 38 degrees C, 20 to 40 p. 100 of the spermatozoa remain motile in two-thirds of the samples; -- 95 p. 100 of immature calf oocytes reach metaphase II after 24 hrs. of culture in the presence of gonadotropins; -- 57 p. 100 of Rabbit morulae divide during 50 hrs. culture as compared to 40 p. 100 in HAM F/10 medium; -- 65 p. 100 of the Cow blastocysts hatch in vitro as compared to 18 p. 100 with Brinster medium.