A total number of one hundred and eight of both Mulard and Muscovy drakes at 12 weeks of age were individually weighed, wing banded and divided randomly into three groups of three replicates, each of six birds. Average of initial body weight of drakes was similar among all groups (x̄). Drakes of the first group were fed ad-lib the same ration of the force feeding . The second group fed the force feeding ration without any added enzyme, while the third group was fed the force feeding rations plus Avizyme 1502 enzyme 0.05%. The results showed that Mulard ducks were highly significant in all carcass traits studied (final live body weight, and percentages of carcass, liver, total giblets and edible parts) than Muscovy ducks. The ether extract percentage was insignificant in meat of the Mulard ducks compared with Muscovy ducks, while, the moisture, crude protein and ash percentage were significantly higher in Mulard ducks when compared to Muscovy ducks. Liver of Mulard ducks contained highly significant moisture, crude protein and ash percentages compared to liver of Muscovy ducks. however, liver of Muscovy ducks contain highly significant ether extract percentage compared to liver of Mulard ducks. Liver of Muscovy ducks was highly significant in LDL (mg/dl) and cholesterol (mg/dl) and insignificant in total lipids weight (mg/dl), triglycerides (mg/dl) and HDL (mg/dl) compared to Mulard duck. Blood plasma for Mulard ducks was highly significant in total protein (g/dl), albumin (g/dl), globulin (g/dl), A/G ratio and insignificant in LDL (mg/dl) and AST (U/L) compared to the Muscovy ducks. On contrary, blood plasma of Muscovy ducks was highly significant in total lipids (mg/dl), cholesterol (mg/dl), triglycerides (mg/dl), HDL (mg/dl), glucose (mg/dI) and insignificant in ALT(U/L), compared to Mulard duck.
Conclusively, Mulard ducks are suitable for force feeding than Muscovy ones to achieve a fast increase in body weight in a short time. Also, to have a high quality of fatty liver which have a high marketing value indoors and outdoors