The present study was performed to study the effect of addition of dried rumen contents in the diet of growing ducklings on performance, carcass traits and some blood biochemical constituents. Sixty Muscovy ducklings of two weeks old were randomly distributed into 5 groups each of 12 ducklings. The first group was considered as a control and was fed adlibitum on a grower/ finisher diet. The other four groups were fed diets containing dried rumen content at levels of 5, 10, 15 and 20% respectively. All diets were formulated to be isocaloric (3000 kcal/kg ME), isonitrogenous (16% CP) as recommended by NRC (1994) for growing ducks. The experiment was extended for 10 weeks. Performance characteristics were assessed. In addition, some blood constituents, carcass traits, mortality rate and economical evaluation were also measured. The results showed that, there was no mortalities in control group and groups fed diets with 5, 10 and 15% dried rumen content, while group fed diet with 20% dried rumen content recorded 8.33% mortality rate. The inclusion levels (0, 5, 10, 15 and 20%) of dried rumen content to the duck diets did not significantly influence the live body weight, body weight gain, feed intake, feed conversion ratio, protein efficiency ratio and caloric efficiency ratio at any growth phase. There were no significant differences between control group and other treatments in carcass dressing percentage and relative percentage of internal organs (heart and spleen). While there were significant (P < 0.05) differences in relative percentage of internal organs (liver, gizzard and proventriculus) between control group and other treatments. Also, there were no significant differences in the level of serum total protein, albumin, globulin and uric acid between control group and other treatments. It could be concluded that, using DRC as untraditional feed ingredient in diets of growing ducks up to 20 % will share in decreasing environmental pollution and lowering the feed cost without any adverse effect on the duck performance.