Carcass characteristics, meat quality, and functional compound deposition in sheep fed diets supplemented with Astragalus membranaceus by-product

•Carcass characteristics are not adversely affected by Astragalus by-product addition.•Astragalus by-product decreases fat content in the Longissimus dorsi muscle.•Astragalus by-product decreases drip loss in the Longissimus dorsi muscle.•Astragalus by-product stimulates the accumulation of aspartic acid in mutton.•Astragalus by-product addition influences bioactive compound deposit in sheep. This study was conducted to investigate the effects of dietary supplementation of Astragalus by-product (ABP) on carcass characteristics, internal organ development, meat quality, and functional compound deposition in sheep. Twenty-four Doper x Small Tail Han female lambs (6–7 months of age; 29.07 ± 2.28 kg initial body weight) were randomly assigned to one of three treatments for a 47 d feeding period. Treatments consisted of dietary supplementation with 0 %, 10 %, or 15 % of ABP (dry matter basis). Bioactive compounds in ABP, liver, and muscle were analysed by the UHPLC-QTOF-MS procedure. Dietary ABP supplementation did not affect (P > 0.05) carcass characteristics and internal organ development indicators except kidney weight which increased linearly (P = 0.019). ABP inclusion had no effect (P > 0.05) on moisture, crude protein (CP), and ash composition in the Longissimus dorsi (LD) muscle. Fat content in the LD muscle decreased (P