Validation of in vitro digestion using simulated small intestinal fluid with specific digestive activity to predict the metabolizable energy of feed ingredients for duck. (4th October 2018)

• Record Type: Journal Article
• Authors: Zhang, L; Zhao, F; Zhang, H; Bian, G Z; Wang, Y M; Yang, X; Li, H
• Is Part Of: Poultry science. Volume 98:Number 3(2019:Mar.)
• Page Start: 1280
• Page End: 1287
• Publication Date: 2018-10-04
• Subjects: simulated small intestinal fluid -- duck -- in vitro digestion -- metabolizable energy; Poultry -- Periodicals; Poultry -- Periodicals; Poultry Diseases -- Periodicals; Electronic journals; 636.5005
• DOI: 10.3382/ps/pey450
• Languages: English
• ISSNs: 0032-5791

Abstract

ABSTRACT: Two experiments were conducted to validate a method to prepare simulated small intestinal fluid (SSIF ) for in vitro digestion in ducks. Experiment 1 compared the in vitro digestible energy (IVDE ) of SSIF to endogenous small intestinal fluid (ESIF ) on four feeds. The ESIF 1 or 2 obtained from two groups of jejunal cannulated ducks offered diet 1 (3, 050 kcal/kg of ME and 19.95% of CP) or 2 (2, 801 kcal/kg of ME and 14.90% of CP) was purified into raw enzyme power (REP ) 1 or 2. SSIF 1 to 3 or 4 to 6 were prepared to mimic ESIF 1 or 2, respectively. The enzyme sources were REP 1 for SSIF 1 and 4, REP 2 for SSIF 2 and 5 or reagent enzymes for SSIF 3 and 6, respectively. The IVDE of each feed was determined with SSIF or ESIF. Experiment 2 was to validate whether REP 1 was more effective than only reagent enzymes to prepare SSIF. Ten feeds were determined with pepsin following SSIF 1 or 3 for IVDE 1 or 2, respectively. The accuracy of prediction model of true metabolizable energy (TME ) from IVDE 1 or 2 was evaluated to validate the efficacy of SSIF. In experiment 1, higher activities of amylase, trypsin and chymotrypsin were observed in ESIF 1 than ESIF 2 ( P < 0.05). The IVDE determined with SSIF 1 and 2 or 3 and 4 were more comparable to that of ESIF 1 or 2 than determinations with SSIF 3 or 6. In experiment 2, the mean IVDE 1 or 2 was 97.22% or 96.23% relative to TME, respectively, and both were highly correlated with TME ( P < 0.01; R 2 ≥ 0.98). However, the residual SD of TME prediction model with IVDE 1 was less than that generated with IVDE 2 (55 vs. 71 kcal/kg). In conclusion, the IVDE determined with in vitro digestion of pepsin following SSIF prepared with REP can predict accurately TME of feed for ducks.