The Effect Of Gonadal Hormone To Gonadal Differentiation And Development Of Early Chick Embryo

This present work seeks to study the effect of testosterone propionate and estradiol's treatment dose as well as time to early chick embryo gonadal development, survival rates, and body weight. 320 or 360 eggs weighted 60.00 g±0.10 g were injected 0.00 ml(Ⅰ),0.05 ml(Ⅱ),0.10 ml(Ⅲ),0.20 ml(Ⅳ) of testosterone propionate and estradiol when hatched for 0 d(T1),3 d(T2),6 d(T3),9 d(T4), respectively. Gonad development, survival rates and body weight were observed when they were hatched for 18 days. Ocular estimate was used to observe the effect of T and E to gonadal development, besides, along with PCR, we finally confirm the chick sex, the effect of T and E to chick embryo survival rates as well as body weight. The results were as follows:1 The effect of T,E to chick embryo gonadal development.The results showed that T and E can affect significantly the development of chick embryo gonad (P<0.05), which help the development of bilateral testicle of rooster and the right ovary of hen to some extent. After injected T, the abnormal rate of embryo gonad was 19.88%, including 6.02% of rooster gonad, 13.86% hen gonad of and 0.60% of inter-sex gonad. Dose and time significantly affect the development of chick embryo gonad (P<0.05). PCR was used to confirm the sex for chicks with abnormal gonad. After injected E, the abnormal rate of embryo gonad was 28.83%, including25.53% of rooster gonad, 74.47% hen gonad. The dose of E and time significantly affect the development of chick embryo gonad (P<0.05)2 The effect of T and E to chick embryo mortalityWhen injected T and E with various dose and time, the chick embryo normal mortality increased up to 8%-9%, which showed the significant difference(P<0.05). When 166 chick embryos were injected by T with increasing dose,Ⅱ,Ⅲ,Ⅳshowed significant difference between each other (P<0.05)exceptⅠandⅡ.237 chick embryos were injected by E with increasing dose,Ⅱ,Ⅲ,Ⅳshowed no significant difference between each other about mortality exceptⅠ0 andⅠ(P<0.05).When injected T at various time, the mortality showed significant difference (P>0.05) except the mortality between T1 andT2 ( P>0.05). T1 had the highest mortality, T4 had the lowest mortality. When injected E at various time, the treatment groups showed no significant difference(P>0.05) except the treatment groups between T0, T2and T1 ,T3, respectively. The chick embryo had lowest mortality in T2.3 The effect of T and E to chick embryo body weight.As the dose of T and E increased, the average chick embryo weight decreased with overall significant difference (P<0.05). After injected T, the treatment groups showed significant difference (P<0.05) except the groups betweenⅢandⅣ. The body weight continually decreased with the increasing dose of T. After injected E, the treatment groups showed significant difference(P<0.05) except the groups betweenⅢ,ⅣandⅡ, respectively.Treatment time of T and E showed different effects on chick embryo body weight. After injected T, the chick embryo body weight showed no significant effect. The treatment groups showed no significant difference (P>0.05) except the groups between, T1,T3,T4 and T2 ,respectively. After injected E, the treatment groups showed no significant difference (P>0.05) except the groups between T0 and the rest treatment groups as well as between T1,T3 and T2 , respectively. When injected T or E, the body weight increased higher after hatched for days than other treatment groups.