Generation of Birds Maintaining Identical Genome

获得了鸡的受精卵。鸡蛋壳在培养皿中破裂。蛋黄周围的大部分蛋白都被去掉了。在胚胎周围放一张滤纸。滤纸周围的卵膜被外科剪刀剪下。获得单独的胚皮。显微镜下观察发育区为透明区或不透明区。从鸡胚皮中分离出多能细胞。将来自囊胚（供体）的细胞注射到受者的雄性或雌性囊胚中以产生种系嵌合体。供体菌株为barbarplyomouth Rock （BPR）或silk。受体菌株为白来鸿。将供体细胞注射到男性或女性受体胚胎中。利用离体培养系统培养制备的嵌合胚胎。根据供体羽毛的黑色色素沉着进行体细胞嵌合。孵出的嵌合体被饲养到性成熟。根据本实验方法，从囊胚中获得了三对雄性和雌性体细胞嵌合体。一对雄性和雌性嵌合体达到了性成熟。雄性和雌性进行交配试验时，产生了一只羽毛上有黑斑的后代，该后代来自于羽毛上的供体菌株（BPR）。有人认为，精子或卵子是由供体细胞产生的。该策略将成为未来培育具有相同基因组（类似于克隆鸟类）的鸟类的有力工具。

Fertilized eggs of the chicken were obtained. The egg shells were cracked on Petri dish. Most of the albumen around the egg yolk was removed. A filter paper was put around an embryo. The egg membrane around the filter paper was cut by a surgical scissors. The blastoderm alone was obtained. The developmental region either area pellucida or area opaca was identified under a microscope. Pluripotent cells were isolated from a blastoderm of the chicken. The cells from a blastoderm (donor) were injected into recipients' male or female blasoderms to generate germline chimeras. The donor strains were either Barred Plyomouth Rock (BPR) or Silky. The recipient strain was White Leghorn. The donor cells were injected into either male or female recipient embryos. The manipulated chimeric embryos were cultured by ex vivo culture system. The somatic chimerism were accessed according to the black pigmentation due to the donor feather. The hatched chimeras were raised until sexual maturities. Three pairs of the male and female somatic chimeras derived from a blastoderm were generated according to the present experimental strategies. A pair of male and female chimeras reached sexual maturity. When the male and female were test mated, one offspring which had black spot derived from donor strain (BPR) in the feather was generated. It was suggested that sperm or ova was generated from the donor cells. The developed strategy should be powerful tool for generation of birds maintaining identical genome (similar to clone birds) in the future.