Effects of Anion Supplementation on Growth Performance, Nutrient Digestibility, Meat Quality and Fecal Noxious Gas Content in Growing-finishing Pigs

Forty-eight ((Duroc${\times}$Yorkshire)${\times}$Landrace) pigs with an average initial body weight (BW) of $48.47{\pm}1.13\;kg$ were used in a 12-week growth trial to investigate the influence of Anion (silicate) supplementation on growth performance, nutrient digestibility, meat quality and fecal noxious gas content in growing-finishing pigs. Pigs were allotted into three dietary treatments in a randomized complete block design according to sex and initial BW. Each dietary treatment consisted of four replications with four pigs per pen. Dietary treatments included: i) CON (basal diet), ii) HCI (basal diet+3 g/kg Anion), iii) HCII (basal diet+6 g/kg Anion). No significant difference (p>0.05) was detected for average daily gain (ADG), average daily feed intake (ADFI) and gain/feed ratio (G/F) throughout the experiment, although dietary supplementation of Anion numerically increased these characteristics compared with CON. The dietary HCI group significantly (p<0.05) increased the coefficient of total tract apparent digestibility (CTTAD) of dry matter (DM), nitrogen (N) and energy compared with the CON group (p<0.05). No significant difference was observed in meat quality except that meat firmness was linearly (p<0.05) increased by the Anion supplementation, while an increased tendency in meat color and a decreased tendency in 2-thiobarbituric acid reactive substances (TBARS) was also observed (p<0.10). Anion supplementation linearly (p<0.05) decreased the fecal $NH_3$ compared with the CON group. However, dietary Anion supplementation at 3 g/kg decreased the $H_2S$ concentration compared with CON, while no significant difference was detected in the HCII group, although the $H_2S$ emission was numerically decreased compared with CON. In conclusion, supplementation of the diet with 3 g/kg Anion was found to exert a beneficial effect on nutrient digestibility and meat quality of growing-finishing pigs, and concomitantly decreased the noxious gas emission without negative effect on growth performance.