Sweet potato vine, the byproduct of sweet potato, has a high nutritional value. Silage is an effective solution for nutrient preservation. This article explored the effects of sweet potato vine silage (SPVS) supplementation on meat quality, antioxidant capacity and immune function in finishing pigs. One hundred and eighty finishing pigs (Berkshire × Licha Black) with a body weight of 74.54 ± 3.32 kg were randomly divided into three groups. The three groups were separately fed basal diet (Ctrl), Ctrl supplemented with 2.5% SPVS (LSPVS) or 5% SPVS (HSPVS) on a dry matter basis. Results showed that the eye muscle area in the LSPVS group was significantly increased. The carcass weight in the HSPVS was significantly reduced compared with Ctrl. For the meat quality, only cooking loss in both HSPVS and LSPVS was reduced while other indexes had no significant differences. For the antioxidant capacity, the hepatic level of glutathione (GSH) peroxidase (GSH‐PX) was significantly upregulated in LSPVS but downregulated in HSPVS. In the serum, HSPVS decreased GSH level and increased GSH‐PX level. HSPVS significantly reduced hepatic interleukin‐1β (IL‐1β) levels and LSPVS significantly reduced IL‐12 levels and increased IL‐8 and IL‐6 levels. Moreover, HSPVS and LSPVS promoted the secretion of immunoglobulin M (IgM) and IgG in the serum. Our data showed that low‐dose SPVS supplementation improved carcass traits and high‐dose SPVS supplementation increased immune function in finishing pigs, which provides a new alternative to improve animal health.

Background Sweet potato vine is the stem and leaf of sweet potato and is nutritious as feedstuff. Silage is an effective solution to retain nutritional value and is beneficial for the preservation. This article explored the effects of Sweet potato vine silage (SPVS) supplementation on meat quality, antioxidant capacity and immune function in finishing pigs. 180 finishing pigs (Berkshire×Licha Black) with body weight of 74.54 ± 3.32 kg were randomly divided into three groups with six pigs per pen and six replicate per treatment: control diet (CON), CON supplemented with 2.5% SPVS (LSPVS) and 5.0% SPVS (HSPVS). Results It showed that eye muscle area in the LSPVS group was significantly increased and carcass weight in the HSPVS was significantly reduced. Cooking loss in both HSPVS and LSPVS were significantly reduced. Hepatic level of glutathione peroxidase (GSH-PX) was significantly upregulated in LSPVS but downregulated in HSPVS. In serum, HSPVS decreased glutathione (GSH) level and increased GSH-PX level. HSPVS significantly reduced hepatic IL-1 level and LSPVS significantly reduced IL-12 level and increased IL-8 level. Moreover, HSPV promoted the secretion of IgM and IgG in serum. Conclusions SPVS supplementation improved animal performance, meat quality, antioxidant capacity and immune performance in finishing pigs, which provide a new alternative to improve animal health and substitute traditional feedstuff.