| Studies on the essential theory and methods of chicken ooctye, embryo manipulation are very important for producing transgenic chicken. It also has great significance for providing the essential contents of the embryology and the development biology. There is a little materials about the chicken ooctye,embryo manipulation so far, Specially, studies on chicken ooctye fertilization in vitro,development early embryo have not been reported in China. So, we carried out the studied and the major contents as follows:1.Study on chick ooctye by fertilization in vitro2. The early development of the chick embryo in vivo3. Transplant embryo and grafted alien blastoderm culture in vitro for chick4. Study on the migration and accumulate of primordial germ cells of the chick embryo5. Study on isolation and culture of primordial germ cells from chick embryos The main results of the experiment summerized as follows:1 Out of a total of 44 recipient hens, 28 are laid. and 7 out of 28 eggs with thin cal-cofied shells. 8 were fertilized of among 28(18. 18%). 6 developed (13. 64%vs75%). 3 living chicks were hatched from 8 fertilized ova (10. 17%vs37. 50%). Though the rate of hatching was low, 3 living chicks were hatched. This approach provides a useful model for producing transgenic chicks.2 The optimum time of obtaining ova is 30—40 min after the offer hen has layed.3 The optimum time for embryo translation is 30±10 min after the receipt hen has layed.4 Embryo can not be transplanted into foster with lower rate of producing eggs.5 Development rate of embryo is 10 percent, which showed embryo can be cultrured in vitro.6 During the development process from cleavage to oviposition in hen's oviduct, the chick embryo can be divided into two stages according to the morphologic change of blas-todisc, (1) Cleavage stage has been failed into 5. 5 h~15. 5 h after the first egg layed. It forms results is the formation of blastodisc with 5— 6—cell layer thick and has two thousandblastomere. At this period, blastodisc has been splitting, but undifferentiation , and blas-tomere has greater plasticity and potential of differentation. (2) Formation stage of area pellucida has been failed into 17. 5h — 23 h after the first layed egg. At last, it formed a thin area pellucida in the center of blastodisc, and the area opaca surrounding, The stage is difined as the late blastula stage. At this period,the blastomere has greater plasticity also.7 After 5. 5 h of the first egg layed,two cleavage has occured in embryo,this proves the first cleavage takes place before 5. 5h. At the first 7. 5h, division of chick zygote is e-qual, The event happened every half an hour,then the rate of division speeds up and the cleavage showes irregular.8 The first division of fertilizating egg occurs in 5h following the hen layed, the maru-la occurs in 11. 5h,and blastula occurs in 15. 5h.9 During 1~7. 5h after the hen layed, all of the blastomere are open up.10 A series of photographes of chicken embryo development have been taken , this is on unprecedented repord.11 Egg were turned db 45° in hatching box,the embryo development rates of small surrogate eggshells and double—yolk surrogate eggshells were 48. 5% and 21. 1% respetive-ly, and the difference is significant. However, hatching rate of double — yolk surrogate eggshells and small surrogate eggshells were 8. 3% and 0% respetivityly, and the difference is significant also. When embryos cultured in the double —yolk surrogate eggshells, transplanting embryos did not need add albumen ..salt solution and so on.12 The results of embryos of chicken grafted alien blastodern, showed isonutrient may be used as common nutrient within the embryo of the same chick breed.13 Chick PGCs originate from area pellucida of unincubated blastoderm , then translocate and gether in germinal crescent area in the junction of the area opaca and area pellucida lateral to the primitive streak at stage 5(incubated for about 22h). later on,they enter the blood vascular system and appear first in the embryo proper at stage 10(icubated for about 36h), and surround in the heart,big blood vessles and head of chick embryo after incubated for 48—56h(stage 12— 16)..and finally leave the blood vessels and settle down in the go-nadal anlagen at stage 17 —22(incubated for about 62h). PGCs gather during three periods: first, at hatching for about 22h (at stage 5);Second, at hatching for about 44—52h (at stage 11 — 13) and third, at hatching for about 62h (at stage 17).14 After 32h of hatching most of PGCs distribut in blood vesses of area pellucida. This demonstrates that the PGCs has moved into the blood vessel outside the embryo.15 3—IOjj.1 blood per chick embryo was collected at 48h,52h,,54h,56h,60h for isolating PGCs. Concentrations of PGCs were 0. 24%, 1. 21%,1. 02%,0. 64%, 0. 27% resp. PGCs concentrations increased from 0. 01% of pre—collection to 1. 02% after collection.16 PGCs were cultured in the medium with TCM—199 Containing 10% FCS,under 38. 5X2 5% CO2 and saturation moisture in vitro, they could survive for about 3—4 days.17 When embryos were hatched for 53—56 hours, the PGCs reached the place called epithelial tissue of body cavity where gonadal will be formed. The place begins to grow thick before the PGCs reach , this proves that the genital ridge occurs at this time.18 The method of collecting blood samples from embryo hatched for 48'—60h is cut off the yolk vein in front of the embryo.19 At the 3. 5—5th hatching day, the glycogen of the PGCs plasma have been reducing gradually. At the 6th hatching day, the gonadal of the sample has the character of the ovary in chick embryo, and the glycogen of PGCs plasma have further reduced, the result shows the gonadal of chick embryo are forming at this stage.20 At the 7th hatching day, the differentiation of ovary or testis is obvious. The glycogen in the PGCs plasma have vanished completely, and PGCs are differentiated into oogonia or spermatogonia.
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