Chestnut tannin extract modulates growth performance and fatty acid composition in finishing Tan lambs by regulating blood antioxidant capacity, rumen fermentation, and biohydrogenation.

Tannins as plant extracts have emerged as promising and potential alternatives for antibiotics in modern livestock cultivation systems. This study investigates the effect of dietary chestnut tannin extract (CTE) in finishing Tan lambs. Twenty-seven male Tan lambs were randomly divided into three groups: (1) control group (CON; basal diet); (2) low-dose CTE group (LCTE; basal diet + 2 g/kg CTE, dry matter [DM] basis); (3) high-dose CTE group (HCTE; basal diet + 4 g/kg CTE, DM basis). The HCTE group exhibited markedly higher average daily gain (ADG) and DM intake than CON (P < 0.01). The ruminal total volatile fatty acid concentration increased linearly with increasing CTE supplementation (P < 0.01), while the opposite trend was observed for butyrate molar proportion (P < 0.01). Upon increasing CTE dosage, plasma glucose, high-density lipoprotein cholesterol, glutathione peroxidase, and superoxide dismutase content increased linearly (P < 0.05), whereas low-density lipoprotein cholesterol and urea nitrogen decreased linearly or quadratically (P < 0.05), respectively. A linear increase was also observed in ruminal t6 C18:1 and t9, c12 C18:2 proportions (P < 0.01), and plasma C18:2n-6 and n-6 polyunsaturated fatty acids proportions with increased CTE supplementation (P < 0.01). In the longissimus dorsi muscle, the atherogenic index decreased linearly (P < 0.05), while c11 C18:1 and C20:5n-3 increased linearly (P < 0.05). Moreover, c9, t11 conjugated linoleic acids proportion increased in subcutaneous fat with CTE supplementation (P < 0.01). In conclusion, Dietary CTE enhances the ADG of finishing Tan lambs in a dose-dependent manner, modulates plasma metabolites and antioxidant capacity, and improves rumen fermentation and body fatty acid composition. These results provide a reference for the rational application of CTE in ruminant production.

Transcriptome analysis reveals the effects of Schizochytrium sp. on the meat quality attributes of Tan lambs.

Schizochytrium sp., a feed additive, positively affects the quality of animal meat. In this study, the molecular mechanisms through which dietary Schizochytrium sp. affects the meat quality characteristics of Tan lambs were investigated using transcriptomic techniques. The findings demonstrate that the lambs supplemented with Schizochytrium sp. had a larger loin eye area and a higher average daily gain and intramuscular fat content (P < 0.05). They also had lower drip loss (at 24 and 48 h) and shear force (P < 0.05). Further, 745 genes were differentially expressed between lambs supplemented with Schizochytrium and the control group. Moreover, KEGG pathway analysis showed that the ECM-receptor interaction pathway, which is related to muscle generation and intramuscular fat deposition, was significantly enriched in the lambs administered a diet containing Schizochytrium sp. Herein, we identified some pivotal genes linked to muscular system development and lipid metabolism. Thus, using Schizochytrium sp. may boost the meat quality of Tan lambs by modifying the expression of genes related to hub pathways. The results supply a new basis to determine the molecular mechanisms through which Schizochytrium sp. supplementation regulates the meat quality characteristics of sheep.

Lipidomics analysis reveals the effects of Schizochytrium sp. supplementation on the lipid composition of Tan sheep meat.

Schizochytrium sp. (SZ) can potentially be employed in nutritional strategies for producing high-quality sheep meat. However, the effects of SZ on the lipid composition of sheep meat are insufficiently understood. In this study, the effects of SZ supplementation on the lipid profile of Tan sheep meat were evaluated using non-targeted lipidomic techniques. Lipidomics analysis revealed 383 differential lipids (DLs) between the SZ and control groups, and there were six metabolic pathways associated with lipids, including glycerophospholipid metabolism, glycerolipid metabolism, α-linolenic acid metabolism, linoleic acid metabolism, glycine, serine and threonine metabolism, and arachidonic acid metabolism (P < 0.05). Glycerophospholipid metabolism was the core pathway of DLs; we found that phosphatidylcholine, phosphatidylserine, and lysophosphatidylcholine were the crucial lipid metabolites of this pathway. Dietary supplementation with SZ increased n-3 polyunsaturated fatty acid (PUFA), C22:6n-3, and C20:5n-3 (P < 0.05), while it decreased C18:0, saturated fatty acid (SFA), and SFA/PUFA (P < 0.05). These results indicate that SZ supplementation induces positive alterations in the lipid profile of Tan sheep meat, which is beneficial to meat quality and sheds valuable insights into the future development of functional lipids in sheep meat.