Selecting And Crossbreeding Of Quality Spotted Chicken And The Genetic Variances Analyzing Between The Spotted Chicken And Other Broiler Breeds By RAPD

In order to promote the quality spotted chicken production in Fujian, we Selected a sire from Youxi chicken, and used the Recessive White Chicken as a matting line, and analyzed the genetic variances between the spotted chicken and other broiler breeds by RAPD.The results were as follow: Compared to the original Youxi chicken group, the sire had increments of 20 eggs in 72-week EN (egg number), 8% in egg-lay ratio,and a decrease of 0.47 in feed-meat rate. The first crossbred progeny delaied laying with 14 days, increased the laying weight with 530g and 72-week EN with 28 eggs, compared to the sire, and the changes were very significant (PO.01), while the changes of fertilized rate and the hatched rate weren't significant (P>0.05). The 10-week weight mean of the first and second crossbred progenies and Youxi chicken were 1320g, 1032g and 634g, respectively; and their feed-meat rate were 3.58, 3.88 and 4.33, respectively, the improvements were significant (P<0.05). However, the three groups' shank and feather color segregated seriously, the segregation ratio were 58%, 54.1% and 5%, respectively, which might be due to that the color is multigene decided, and the spotted is an unstable trait ,and not all color genes are recessive in the Recessive White Chicken. The carcass measuration after the sire Youxi chicken slaughtered shew that the male chicken carcass was superior to the female with 3.32%, 0.36% and 1.98% respectively higher in dressing rate, bresket cut and ham cut, so was the disociated amino acids (P>0.05), but the female ham had more minerals (P>0.05), amino acids (P<0.05), etc.RAPD was used with 28 primers to discover the genetic relationships among the following 15 groups: Hetian chicken (H),Silkies chicken (Si), Recessive White chicken (W), and 3 breeding chicken colonies selected from Youxi sported chicken (Maji chicken): the sire Youxi chicken (Mo), the spotted plumage and black meat (MBo) and the black plumage and meat (BB0), and 3 crossbreds which are the hybrids between the Recessive White and the 3 breeding chicken colonies of Youxi spotted chicken : the black plumage and meat (BB,), the black plumage (B1) and the spotted chicken (Mi), and the sire and dam of three foreign broiler breeds: AA(Arbor Acres), Avain, and Cobb. The major results were as follows. First, the average similarity coefficient of these 15 colonies was 71.2%, ranging from 49.1% to 81%. Secondly, the similarity coefficient between the sire Youxi chicken (M0), the crossbreds, Hetian chicken (H) and Silkies chicken (Si) are higher than those between M0and the foreign breeds, which might be due to they came from different areas, and the results shew the special genetic structure of Chinese chicken breeds.