LAUSR

A series of experiments were conducted to examine the developmental potential of cryopreserved gonadal germ cells (GGCs) recovered from both males and females on embryo day 7 (7 d-GGCs) using the PBS(-) method. Germline chimeras were produced by transferring 200 frozen/unfrozen 7 d-GGCs recovered from female/male Rhode Island Red (RIR) embryos into the dorsal aorta of 2-day-old female and male white leghorn (WL) embryos.Germ-cell recipient embryos were hatched and raised to sexual maturity and progeny testing was conducted by mating with RIR of the opposite sex. Brown-feathered progeny chicks were hatched in all eight possible progeny testing combinations, except for male GGC recipients produced by transferring female GGCs. Furthermore, brown-feathered progeny chicks were hatched when frozen-thawed sperm from male germline chimeras, produced by transferring unfrozen 7d-GGCs, were inseminated in normal female RIR and female WL germline chimeras.The results indicated that cryopreserved female/male GGCs from 7-day-old chick embryos, recovered using the PBS(-) method, were fully capable of developing into normal spermatozoa and ova in the gonad of recipient embryos under appropriate GGC donor/recipient combinations.