Effects of different selenium source on selenium distribution, loin quality and antioxidant status in finishing pigs

The experiment was conducted to study the effects of different selenium source on selenium distribution, loin quality and antioxidant status in finishing pigs. A total of 108 castrates (Duroc × Landrace × Yorkshire) at average body weight (BW) of 60 kg were allotted to three treatments, each of which was replicated three times with 12 pigs per replicate (four per pen). The control groups received the basal diet containing 0.045 mg Se/kg. A 0.3 mg Se/kg in forms of sodium selenite or selenomethionine was added to the basal diet for the experimental groups. The total test period was 40 d. Results showed that selenomethionine-treatment increased the Hunter a (redness) value of meat color during 45 min, 8 and 16 h measurement period (P<0.05) and decreased the drip loss of loin muscle during 8 and 16 h measurement period (P<0.05), while sodium selenite-treatment only elevated the Hunter a value of meat color during 0.75 h measurement period (P<0.05) and had no significant effects on drip loss of loin muscle tissues. Both selenomethionine and sodium selenite-treatment increased the Se content in serum, muscle, liver, pancreas and kidney tissue (P<0.05), the level was substantially higher in muscle, liver and pancreas (P<0.05) in the selenomethionine treated group. In addition, both selenomethionine and sodium selenite-treatment increased glutathione peroxidase (GSH-Px) activity (P<0.05) and decreased the malondialdehyde (MDA) content in the liver and muscle (P<0.05) when compared with control group, but the level of magnitude was higher when selenomethionine was fed. The present study suggests that compared with sodium selenite, selenomethionine is more effective in depositing Se in tissues, enhances the antioxidant status, thus decreasing the volume of drip loss and stabilizing the meat color.