Effects of the Dietary Inclusion of Allium mongolicum Regel Extract on Serum Index and Meat Quality in Small-Tailed Han Sheep

SIMPLE SUMMARY: Allium mongolicum Regel, a typical herb of the Allium family, is rich in a variety of active ingredients, such as flavonoids, essential oils, and polysaccharides. Our previous studies have reported that the dietary supplementation of lambs’ diets with flavonoids from A. mongolicum Regel could promote growth performance and improve the meat quality and mutton flavor of lambs. However, the flavonoid extraction process is complicated, time-consuming, and costly, making it difficult to apply in practical production. A. mongolicum Regel ethanol extract (AME) is easier to obtain and less expensive than flavonoids. AME also contains many bioactive compounds. In the present study, we investigated the effects of AME on the serum index and muscle physicochemical characteristics, as well as the amino acid and fatty acid composition in Small-tailed Han sheep. The results indicated that AME could regulate lipid metabolism and promote the deposition of free amino acids and unsaturated fatty acids in the longissimus dorsi muscle of lambs. These findings suggested that AME could be used instead of flavonoids to improve the body health and meat quality of lambs in practical production. ABSTRACT: The aim of this study was to evaluate the effects of Allium mongolicum Regel ethanol extract (AME) on the serum index and meat quality of lambs. A total of 30 male Small-tailed Han sheep (3 months old) with an average weight of 33.60 ± 1.23 kg were divided randomly into one of two groups: the control group (CON) was offered a basal diet, and the AME group was offered a basal diet with supplementation 2.8 g·lamb(−1)·day(−1) AME. The trial lasted for 75 days. AME supplementation significantly decreased the concentration of triglyceride and total cholesterol (p < 0.05), and tended to lower the concentration of non-esterified fatty acids (0.05 < p < 0.1), but significantly increased the concentration of high-density lipoprotein, leptin, and insulin (p < 0.05) in the serum of lambs. AME also decreased cooking losses and shear force and increased the content of intramuscular fat in the longissimus dorsi (LD) muscle of lambs (p < 0.05). In addition, there was no difference in the composition of hydrolyzed protein amino acids in the LD muscle among treatments (p > 0.05). However, AME changed the composition of free amino acids and promoted MUFA and PUFA deposition in the LD muscle of the lambs. These findings indicate that a diet supplemented with AME may improve the lipid metabolic capacity and meat quality of lambs.