Study on Body Size and Carcass Traits of F_2 Offspring of Large Duck and Improved Liancheng White Duck

The carcass and body size traits of 164 F2 offspring of large duck and improved Liancheng white duck which at 70 days age were determined and analyzed. The results showed that the live weight, leg muscle weight of male ducks were significantly higher than female ducks(P0.05) and the body length, half-length dive, neck length were extremely significantly higher(P0.01). In contrast, the subcutaneous fat rate in male ducks was extremely significantly lower(P0.01)than female ducks. The breast muscle ratio showed significantly positive correlation with live weight, body length, chest depth, chest width, keel length(P0.01). The leg muscle ratio had significantly negative correlation with live weight, body length, chest depth and chest width(P0.01). And the subcutaneous fat rate had significantly positive correlation with live weight, chest width and keel length(P0.01). It indicated that the correlation of carcass traits such as breast muscle ratio, leg muscle ratio and subcutaneous fat rate with body size traits were various in grade. It was necessary to overall consider the various indicators in the process of meat duck breeding. The selection standard must be according to the selection indicators.