Effect of different levels of roasted guar (Cyamopsis tetragonoloba L.) korma with or without β-mannanase supplementation on performance and carcass traits of broilers

An experiment was conducted to evaluate the effect of different levels of roasted guar korma with or without mannanase supplementation on performance and carcass traits of broilers. Nine hundred and sixty day old commercial broiler chicks (Vencobb-400 strain) were divided into sixteen treatment groups of 60 each for six weeks. The diet without roasted guar korma served as control. The rest of the diets were formulated by incorporating 10%, 12.5%, 15%, 17.5 % and 20% levels of roasted guar korma, partially replacing soybean meal with and without enzyme (beta-mannanase) at two levels (500 g/t and 750 g/t). Body weight gain at the starter phase was found to be non significant however at the finisher phase the differences were significant (P<0.05) for T2 (563.35 g) and T5 (533.55 g) than the rest of the groups including control. Differences of feed consumption were significant (P<0.01) at the end of starter as well as finisher phases whereas FCR differences were found to be non-significant. Dry matter digestibility was observed significantly better in T5 group. Significantly (P<0.01) better nitrogen retention was observed in T5 and T6 groups than the groups having higher levels of roasted guar korma. Eviscerated weight differed significantly (P<0.01) whereas non-significant differences were observed for giblet per cent, abdominal fat per cent, edible meat per cent and dressing per cent. It was concluded that 12.5 per cent of roasted guar korma with supplementation of beta mannanase @ 500g/t can be safely added in the broiler diet without any adverse effect on performance, nutrient digestibility as well as carcass trait.