A Study On The Selecting And Breeding Of The Multiplication Line Of Shanma Ducks

China is one of the major countries to feed ducks in the world, with very rich resources of duck varieties. In Fujian Province alone, we have such breeding varieties as Shanma Duck, Jinding Duck, Putian Black Duck and Lianchen White Duck. Shanma Duck is an excellent local egg-laying variety in our country. Being small in size, productive, with less comsumption of feed and high stress-resistance, it is the main variety of egg-laying ducks in our province at present. But Shanma Duck is still being put into commercial reproduction by pure breeding. The way to select and breed the best multiplication strains of Shanma Shelduck is:to select and breed the specialized strain first, and then to carry out the cross-hybriding between the strains and check their combining abilities. It is expected that this will better increase the egg-laying quantity and protect the local resources of the breeding varieties. Once the work is successful, it will make the genetic resources into productivity, and improve the market competitive ability and the market share, increasing the economic benefits for the institutes of scientific research and hybrid duck reproduction enterprises and laying the scientific foundation for the modernization and intensive production of the egg-laying ducks.Selecting and breeding the specialized strain of Shanma Duck are the breeding of the specialized strains and the testing of their combining ability to choose the best ones. Some have been selected in this research, they were Shanma Shelduck StrainⅠ(S1S1), StrainⅡ(S2S2), StrainⅢ(S3S3), Putian Black Duck (PP) Jinding Duck (JJ) and the pure Minnong White Duck (FF). According to the features of each strain and breeding variety, mainly chose their differences, and with the method of selection on generation substitution to select and breed each one of them for 3-5 generations, produced the specialized strain which have stable inheritance and come up to the requirements. And then through a testing of their general combining ability (GCA) and the specific combining ability (SCA) of StrainⅡand StrainⅢ, we selected a Two-Line female parent (PS1,PS2,S1P,FS1 and S1F) for Three-Line hybridized combination, and three best Three-Line combined crosshybrids for commercial reproduction:F (PS2),(S1F),F(S1P). The number of eggs to 500 days old (NE-500d), the total egg weight(EW) and feed/egg ratio(F/E) were 345.4, 25.12kg,2.60:1; 339.2,24.26kg,2.68:1 and 331.1,24.13kg,2.67:1, an increase of 10.3—15.1%,21—26.1% and 8-10.6% respectively compared to the 300.2(NE-500d),19.9kg(EW) and 2.91(F/E) of the parent line of Shanma Shelduck S1S1, reaching the best level in the world of the production performance in the egg-laying shelducks.