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This study was conducted to investigate the effect of Cheju scoria and zeolite on the growth performance, nutrient digestibility and excretion, carcass characteristics of pigs and to evaluate the value of Cheju scoria as a feed additive to reduce environmental pollutions. A total of 63 weaned piglets [D (♂) × LY (♀)] averaging 8.3±0.31 ㎏ of body weight were assigned to the feeding trial for 150 days and 16 growing barrows (averaging 40.5±0.57; four pigs per treatment) to the metabolic trial. The weaned piglets in the feeding trial were divided into three groups and treated in three replicates of seven pigs (4 gilts and 3 barrows) with one of the three experimental diets; con-soybean meal basal (BD), 3% Cheju scoria (CS), and 3% zedite diets (ZD). The based diets were formulated to contain 3,657 kcal DE/㎏ (CP 18.87%), 3,620 kcal DE/㎏ (CP 16.00%) and 3,473 kcal DE/㎏ (CP 15.97%) for starter, grower and finisher, respectively. 3% of com in basal diets was replaced by Cheju scoria or ziolite. All the pigs were slaughtered for carcass analysis at the end of experiment. During nursery period (0 to 39d), average daily gain (ADG) was significantly higher in CS than in BD and ZD (P$lt;0.05), and feed efficiencies in CS and ZD were better than that in BD. For growing period (40 to 109d), ADG and average daily feed intake (ADFI) were significantly higher in CS and ZD than in BD (P$lt;0.05)$gt; but feed efficiencies were not statistically different among treatments. For finishing period (109 to 150d), ADG was significantly higher in CS and ZD than in BD, and ADFI was not affected by the treatments. However, CS showed better feed efficiency than the others (P$lt;0.05). For the entire experimental period (0 to 150d), CS and ZD tended to be higher in ADG and ADFI compared to that of BD, but no significant differences in feed efficiency were observed among treatments. Dry matter (DM), crude protein (CP) and phosphorus (P) digestibilities were significantly higher in CS than that of BD, and there was no difference in nutrient digestibility between ZD and BD. Nitrogen (N) and P excretion were significantly lower in CS than in BD during the nursery period (P$lt;0.05). For the growing period, BD showed significantly lower N and P excretion compared to the control (P$lt;0.05). N excretion was significantly lower in CS and ZD than in BD, and P excretion was lowest in CS for the finishing period. There were no differences in carcass weight and back fat thickness among the treatment. However, carcass grade was much better in CS than in the others. With regard to meat color, Hunter L value was highest in CS, but there were no differences in Hunter a and b value between CS and BD. The results from the present study suggest that Cheju scoria could be a effective feed additive to reduce N and P excretion and to improve growth performance and meat quality of pigs. However, further research is needed to investigate the exact mode of action of Cheju scoria and optimal level of dietary supplementation.
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