The Optimal Nutrients Level Of Metabolizable Energy And Crude Protein In Feeds For Shelduck

Two trials were carried out to investigate the optimal nutrients level of metabolizable energy (ME ) and crude protein (CP) in feeds for Shelduck.The first trial was determined for three periods from the age of 1 day to 7 weeks (0-2 weeks, 3-4 weeks, 5-7weeks) to estimate the suitable nutrients level of ME and CP with the best performance and feed efficiency in Shelduck. Four hundred and fifty ducks were divided into nine equal groups and fed on the diets with different ME (12.92 KJ/kg, 12.19 KJ/kg, 11.49KJ/kg )and CP (23 %,20%,17%) in the first stage. Then 360 ducks were divided into nine equal groups and fed on the diets with different ME (12.92 KJ/kg, 12.19 KJ/kg, 11.49KJ/kg )and CP (20% , 18%, 16%) in the second stage. The third stage is similar to the above.288 ducks were utilized. The diets were crossed with different ME (12.92 KJ/kg,12.19 KJ/kg, 11.49KJ/kg )and CP (23%, 20% , 17%). 8 ducks per group were carried out the metabolism experiment in the 2nd week and the 5th week. Comparative slaughter experiments were carried out in the end. The obtained results are as follows:1. Average daily gain(ADG): 0-2weeks,the 9~th,8~th,1~st group were the lowest, while the 4~th, 5~th group were the best .The difference between the two levels were significantly(P<0.05); 3-4weeks, the 9~th,4~th,8~th,7~th,6~th group were the lowest, while the group 2~nd and 5~th were the best .The difference between the two levels were significantly(P<0.05), The 7~th group is the medium level; 5-7weeks,the 7~th group were the lowest, while the group 6~th were the best. The differences between the two levels were significantly (P<0.05).2. Feed/gain ratio: 0-2weeks, the 1~st,2~nd,5~th,4~th group were the lowest, while the3rd > 7th> 8th > 9th group were the highest .The difference between the two levels were significantly (P<0.05) ; 3-4weeks, the 5th s 1st s 2nd> 3rd> 4 th group were the lowest.The difference among the five groups were not significantly; 5-7weeks,the 7th group were the highest. The differences among the other groups were not significantly.3.Carcass characteristics: The difference of the dressing percentages the semi-eviscerated carcass weight percentages the eviscerated carcass weight percentages the breast muscle percentages the leg muscle percentage among all the groups were not significantly. The abdominal fat percentage of the 4th was the highest, while the 9th was the lowest. The differences between the two levels were significantly (P<0.05).Based on the above experiment, three diets containing different energy source such as maizes rough rices paddy were fed to ducks. The experiment lasted two periods(l -3weeks,4 - 7weeks).The result of the first period showed that the ADG of the group fed rough rice were higher than the group fed paddy significantly (P<0.05)> the ADG of the group fed maize were higher than the group fed paddy ,but the difference was not significantly. The result of the second period was similar to the first period except that the difference between the group fed rough rice and the other two groups increased (P<0.01). The difference between the other two groups decreased. The feed/gain ratio of the paddy group was higher than the other two groups significantly.In conclusion, the results showed that the optimal nutrients level with the best performance were 12.19MJ/kg MEX 20%CP in 0-2weeks; 12.19 MJ/kg MEX 18%CP in 3-4 weeks; 11.49 MJ/kg MEX 16%CP in 5-7 weeks. In practice, it was feasible that rice submitting maize completely and paddy submitting maize partly were conducted in diets.