Effect Of Dietary Supplementation Of Selenium And Vitamin E On Growth Performance And Meat Quality And Antioxidant Ability In Finishing Pigs

The experiments were conducted to investigate the effect of dietary supplementation of selenium and vitamin E and oxidized fish oil on the animal performance,oxidation resistance and pork quality of finishing pigs.40 Crossbred Pigs(Duroc×Landrace×Yorkshire) with an average weight of 59.4 kg were individually penned and allotted into four treatments to feed basal diet and three experimental diets containing 0.3 mg/kgSe,100 mg/kgVE and 0.3 mg/kgSe+100 mg/kgVE. Each treatment was divided into two groups of 5 pigs each and fed diets containing either 5%fresh(POV=36.40 meq kg^-1) or 5%oxidized(POV=104.62 meq kg^-1) fish oil in the phase of averaging 81.3 to 109.8 kg.At 109.8 kg of BW,40 pigs were slaughtered to determine carcass and pork quality.The results showed as follow.(1) Supplementation of Se+VE significantly increased SOD,GPx activities and reduced BUN,MDA levels in serum(P＜0.05) at 81.3kg BW and 109.Skg BW for fresh oil group,and there was a trend of increase on performance and nutrient digestibilities with Se+VE supplementation during 60～110kg BW.Supplementation of Se+VE increased the dressing percentage(P＜0.05),improved a^* and b^* values of meat color(P＜0.05),and trended to increase lion eye area.Supplementation of VE decreased drip loss and MDA contents of meat(P＜0.05).(2) Pigs fed diets containing oxidized fish oil without additives had significantly higher serum malonaldehyde and BUN contents than pigs fed fresh oil diet(P＜0.05),and lower performance and nutrient digestibilities.Pigs fed diets without additives and oxidized fish oil showed reduced dressing percentage,and increased b^* value,MDA content of meat,indicating a response to oxidative stress(P＜0.05).Muscle fibers from oxidized fish oil showing significant exudation of endochylema. (3) Pigs fed diets with Se+VE and oxidized fish oil had higher SOD,GPx activities and lower BUN,MDA levels in serum than those fed diets without additives and oxidized oil and showed better results of ADG,DE digestibilities and SOD than those fed diets with Se+VE and fresh fish oil.Se supplementation showed higher GPx activity in oxidized oil than in fresh oil.The interactive effect of the fat and additives was observed significantly (P＜0.05).Pigs fed diets with Se+VE and oxidized fish oil showed significant better results of dressing percentage,meat color and MDA content than those of fed diets without additives and oxidized oil,and showed better result of a^* value of meat than that of fed diets with Se+VE and fresh fish oil.VE supplementation reduced drip loss to a greater extent for oxidized oil than fresh oil.The interactive effect of the fat and additives was observed in a^* value and drip loss(P＜0.05).Additive supplementation could alleviated the impacts of oxidized fish oil on muscle fibrous structure.The results indicated that supplementation of Se or VE or combination of Se and VE in finishing pigs diets could alleviate the impacts of oxidized oil on meat and meat products with the combination of Se and VE being the best.