Use of duckweed (Lemna perpusilla) as a protein source feed item in the diet of semi-scavenging Jinding layer ducks.

摘要

This experiment was conducted for a period of 75 days on a farm house to investigate the effect of feeding duckweed (Lemna perpusilla) that replaced conventional protein supplement mustard oil cake (MOC) in the diets of Jinding ducks. The experiment included a total of 84 laying ducks with 4 treatments, 3 replicates and 7 ducks per replicate. The diets were based on rice byproducts with soyabean meal and mustard oil cake as protein sources. The control diet A contained 15% MOC, and 5, 10 and 15% MOC were replaced with dry duckweed in diets B, C and D, respectively. The birds were raised under extensive system, and feeds were supplied 2 times daily before and after herding. The replacement of MOC by duckweed insignificantly decreased the liveweight gain (P>0.05), egg weight (P>0.05) and feed conversion efficiency (P>0.05) but significantly increased egg production (P<0.01) and profitability (P<0.01) through reduction of the production cost of feeding. Body weight gain and egg productivity showed a linear declining trend as the proportion of duckweed in the diet was increased. Considering the economic benefits, it might be recommended to replace MOC with duckweed up to 15% level in the diet of laying ducks.