Effects of partial replacement of soybean meal with roasted guar korma and supplementation of mannanase on performance and carcass traits of commercial broiler chickens

Abstract

Aim: To evaluate the effects of inclusion of roasted guar meal, also known as guar korma, as a partial replacement for deoiled soybean meal (SBM) in commercial broiler diets, on production performance and carcass traits of Cobb-400 broiler chickens.Materials and Methods: 1600 one-day-old Cobb-400 broiler chicks were randomly assigned into four dietary treatments, each with four replicates (n = 100 chicks per replicate). The diets were iso-nitrogenous and iso-caloric and included the basal diets composed of maize and SBM (T0), T0 + â-mannanase (T1) and the treatment diets in whichSBM was partially replaced (20 g/kg in pre-starter, 50 g/kg in starter and finisher) with guar korma (T2) and T2 + â-mannanase (T3).Results: Live weight was unaffected by the dietary treatments (P > 0.05). Guar korma increased feed intake when compared with the SBM fed groups (P = 0.01). Feed conversion was better (P = 0.01) when SBM was fed to the chickens irrespective of mannanase supplementation. As a consequence the performance index score was superior (P = 0.04) in the SBM fed groups when compared to the guar korma fed groups. Across the diets, feed conversion was superior (P < 0.05) in the T1 group suggesting a beneficial effect of â-mannanase in the maize-SBM diet. Dressed yield showed a trend to improve (P= 0.08) upon â-mannanasesupplementation.Conclusion: It was concluded that partial replacement of SBM with guar korma may not yield any substantial benefits in terms of performance and carcass traits and that supplementation of â-mannanase may also not be worthwhile in alleviating the negative effects of guar korma.

Keywords

• â-mannanase
• broiler chickens
• carcass traits
• guar korma
• performance