Comparision of relative bioavailability of Mn proteinate and Mn oxide in young broiler chicks

This study was conducted to evaluate the relative bioavailability value of Mn proteinate and Mn oxide in broiler chicks. A total of 432 day-old Cobb 500 commercial male broiler chicks were randomly distributed into nine treatments with eight replicate pens of six chicks each. In a completely randomized design experiment with a 2×4 factorial arrangement of two manganese sources (proteinate and reagent grade of oxide) with four levels of supplemental manganese (35, 70, 105 and 140 mg/kg diet) was provided by the use of a basal diet (control). Diets were fed from day one to 21 d of age. Manganese sources did not affect feed intake, body weight gain and feed conversion ratio (FCR), but body weight gain and FCR had a quadratic relationship with supplemental dietary Mn level. Tibia, kidney and liver manganese concentrations increased linearly, with increasing dietary Mn level. Tissue Mn analysis indicated that the tibia response to dietary Mn level was the greatest, followed by kidney and liver organs. The slope ratio regression analysis for tibia manganese content with supplemental manganese level revealed that the relative bioavailability value of manganese proteinate to Mn oxide was 101.7%. Thus, the relative bioavailability of Mn proteinate and Mn oxide was almost similar in this study.