Evaluation of Nitrogen-Corrected Apparent Metabolizable Energy and Standardized Ileal Amino Acid Digestibility of Different Sources of Rice and Rice Milling Byproducts in Broilers

Kun Xie; Xi He; De-Xing Hou; Bingkun Zhang; Zehe Song

doi:10.3390/ani11071894

Evaluation of Nitrogen-Corrected Apparent Metabolizable Energy and Standardized Ileal Amino Acid Digestibility of Different Sources of Rice and Rice Milling Byproducts in Broilers

Animals (Basel). 2021 Jun 25;11(7):1894. doi: 10.3390/ani11071894.

Authors

Kun Xie^{1

2}, Xi He^{1

3}, De-Xing Hou^{2

4}, Bingkun Zhang⁵, Zehe Song^{1

3}

Affiliations

¹ College of Animal Science and Technology, Hunan Engineering Research Center for Poultry Safety, Hunan Agricultural University, Changsha 410128, China.
² Course of Biological Science and Technology, United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima 890-0056, Japan.
³ Hunan Co-Innovation Center of Animal Production Safety, Changsha 410128, China.
⁴ Department of Biochemical Science and Technology, Faculty of Agriculture, Kagoshima University, Kagoshima 890-0056, Japan.
⁵ State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing 100083, China.

Abstract

Rice, broken rice (BR), and full-fat rice bran (FFRB) from six different origins were analyzed for their chemical composition, nitrogen-corrected apparent metabolized energy (AMEn), and standardized amino acid digestibility (SIAAD) in 14-day-old and 28-day-old Arbor Acres broilers. Results showed broilers fed with rice and BR had a similar AMEn regardless of the rice and BR having different CP, EE, NDF, ADF, and ash content. FFRB containing significantly different CP, EE, NDF, ADFm and starch presented variable AMEn (p < 0.05), suggesting that starch content in rice and its byproducts contributed most to the AMEn of broilers. The regression equation of AMEn = 14.312 - (0.198 × NDF) and AMEn = 6.491 + (0.103 × Starch) were feasible to integrally predict AMEn of broilers fed to rice and its byproducts. Moreover, 28-day-old broilers had higher SIAAD than 14-day-old ones. The SIAAD of rice were higher than BR and FFRB except for Met, Cys, Thr, and Tyr in 14-day-old broilers (p < 0.05), and the SIAAD of His, Asp, and Ser in BR were higher than FFRB (p < 0.05). In 28-day-old broilers, the SIAAD of Leu, Trp, Asp, Gly, and Pro of rice were still higher than BR and FFRB (p < 0.05), but BR and FFRB had no significant differences (p > 0.05). The regression equations to estimate the SIAAD of Thr, Lys, and Met were: Met = 81.46 + (0.578 × CP), Thr = 0.863 + (6.311 × CP), and Trp = 102.883 - (1.77 × CP), indicating that CP content in rice and its byproducts was likely a major factor for prediction of SIAAD.

Keywords: broiler chicken; nitrogen-corrected apparent metabolized energy; prediction regression equation; rice; rice byproducts; standardized ileal amino acid digestibility.