Significant effect of NSP‐ase enzyme supplementation in sunflower meal‐based diet on the growth and nutrient digestibility in broilers
The digestion of nutrients (sugars, proteins and fats) mainly takes place through endogenous enzymes secreted by the gastrointestinal tract of birds. However, non‐starch polysaccharides (NSPs) that include cellulose, β‐glucans, arabinoxylans and pectins (Dalibard and Geraert, 2004) make up a substantial proportion of the poultry feed and are not digested by the endogenous enzyme system of the bird (Lee et al., 2003) unless supplemented with exogenous NSP‐ase.
The presence of NSPs in the diet has been reported to increase intestinal viscosity of the broilers (Burnett, 1966; Almirall et al., 1995; Austin et al., 1999; Naqvi and Nadeem, 2004) that results in reduced enzymes–substrate interaction (Danicke et al., 2000) leading to compromised nutrient breakdown. Disruption of cell matrix of SFM can be achieved by the addition of exogenous enzymes leading to easy access to the entrapped proteins (Choct and Kocher, 2000). Supplementation of exogenous enzymes to improve performance of birds has been extensively studied and reviewed (Selle et al., 2000; Acamovic, 2001; Cowieson and Adeola, 2005). Adding NSP‐ase enzyme in sunflower–corn‐based diet in broiler chicks has been reported to improve weight gain, FCR and digestibility (Khan et al., 2006). Glamocic et al. (2011) reported that supplementation of exogenous enzyme (Roxazyme) with different levels of ME and SFM in broiler chicks increased the digestibility of CP, NDF, hemicellulose and ash, but the effects were most evident in diets with the reduced level of ME. A commercial multienzyme product (Zympex 008®) is reported to contain α‐galactosidase, β‐glucanase, amylase, xylanase, β‐mannanase, protease and cellulose. A project was envisaged to evaluate this NSP‐ase in sunflower meal‐based diets using broiler for 42 days of trial. The response of birds in terms of growth, FCR, carcass characteristics and nutrient digestibility was examined.