Effect of Exogenous Fibrolytic Enzymes Supplementation or Functional Feed Additives on In Vitro Ruminal Fermentation of Chemically Pre-Treated Sunflower Heads

This study aims to provide possible utilization of sunflower head byproduct (SFH) as a feedstuff by implementing chemical pretreatments (4% sodium hydroxide (SFHNaOH) or 4% urea (SFHurea) and supplementation with either exogenous fibrolytic enzymes (EFE) functional feed additive (FFA). The experimental EFE was complex (1:1, v/v) two enzyme products high activity β-1,3-1,4-glucanase endo-1,4-β-D-xylanase applied at 0 (SFHout), 1, 2, 5, 10 µL/ gdry matter, while FFA fermentation rich in cellulase xylanase activities, 0.5, 4 mg/g DM. SFHurea had the highest (p < 0.05) crude protein (CP) content compared other SFH substrates. Linear enhancements kinetics gas production (GP), metabolizable energy (ME), organic matter digestibility (OMD) total short-chain fatty acids (SCFAs) concentrations were observed for all substrates supplemented EFE. SFHout potential GP, maximum rate (Rmax) ME, OMD SCFAs. Supplementation more pronounced than affecting kinetic parameters vitro GP seems be most promising substrate enhance microbial vitro.