Abstract:

【Objective】 The experiment was conducted to investigate the effect of diet supplemented with selenomethionine (Se-Met) on plasma and tissue selenium content and antioxidant capacity of finishing pigs. 【Method】 Sixty-four crossbred (Duroc×Landrace× Largewhite) pigs (initial BW, 60 kg) were randomly allocated into 4 treatments on the basis of weight following a randomized complete block design. Four replicates were designed for each treatment. Pigs were fed with corn-soybean meal-based diets supplemented with 0 (control) or 0.15 and 0.30 mg•kg-1 Se from Se-Met or 0.30mg•kg-1 Se from sodium selenite (SS), respectively. One barrow per pen was slaughtered when all the pigs were weighed about 95kg on average. 【Result】 All Se-added groups showed significantly increased Se concentration in plasma, liver and longissimus muscle compared with the control (P＜0.01), also 0.30 mg•kg-1 Se (Se-Met) group compared to 0.15mg•kg-1 Se (Se-Met) group or SS group (P＜0.05). Adding Se-Met significantly raised plasma glutathione peroxidase (GSH-Px) activity, catalase (CAT) activity, total antioxidant capacity (T-AOC), and significantly decreased plasma malondialdehyde (MDA) content (P＜0.05). Diet supplemented with Se-Met significantly improved liver GSH-Px, CAT, SOD activity and T-AOC (P＜0.05). All Se-Met groups presented significantly higher liver SOD activity and 0.15 mg•kg-1 Se (Se-Met) significantly increased CAT activity with respect to SS group (P＜0.05). Longissimus muscle GSH-Px activity at 45min post-slaughter was significantly raised and carbonyl protein content was significantly reduced in all Se-added groups (P＜0.05). Longissimus muscle MDA content at different times after slaughter was significantly decreased in all Se-Met groups compared to control, also 0.30mg•kg-1 Se(Se-Met) group compared to SS group at 45min and 72h post-slaughter (P＜0.05). GSH-Px mRNA relative expression of longissimus muscle was significantly increased in all Se-added groups than that of the control (P＜0.05). 0.15 mg•kg-1 Se (Se-Met) group significantly increased SelW mRNA relative expression compared to both control and SS groups (P＜0.05). 【Conclusion】 Compared with the same Se supplementation in the form of SS, Se-Met had greater absorption, deposition rate and antioxidant capacity in plasma and tissues.

Key words: selenomethionine, finishing pigs, Se content, antioxidant capacity