Comparative effects of inorganic and organic manganese supplementation on productive performance, egg quality, tibial characteristics, serum biochemical indices, and fecal Mn excretion of laying ducks

Abstract This study aimed to compare the effects of inorganic and organic manganese (Mn) supplementation on productive performance, egg quality, tibial characteristics, serum biochemical indices, and Mn excretion in laying ducks. A total of 756 Longyan laying ducks (45 wk) were randomly assigned to 9 treatments, each with 6 replicates of 14 ducks. Ducks were fed a basal diet (30.6 mg Mn/kg) or that basal diet supplemented with 20, 40, 80, and 160 mg/kg Mn using inorganic (added as MnSO4·H2O) or organic (Mn-methionine; 8% Mn, 76% methionine) for 20 wks. Supplementation with inorganic Mn increased egg production and mass, and decreased FCR after 10 wk of feeding, and there were quadratic responses between them, and improved performance was observed with 40 mg/kg supplementation (P