| A titanium pillared montmorillonite (Ti-PLM) was prepared and adsorption of arsenic (As) on it was carried out in vitro, as well as in vivo. This study was conducted to investigate the ability of Ti-PLM to adsorp arsenic and the effectiveness of Ti-PLM to protect against arsenosis of pigs and to reduce arsenic residuls in visceral tissues.Adsorption and desorption of As on Ti-PLM was carried out. Various parameters such as reaction time, pH, and temperature were studied to establish optimum conditions. Maximum adsorption capacity was observed at pH 5.0. The adsorption isotherm was also studied by temperature since the adsorption capacity was increased by raising the temperature from 25 to 45℃. The experimental adsorption data fitted reasonably well to the Langmuir and Frieundlich isotherms. Thermodynamic parameters depict the endothermic nature of adsorption and the process is spontaneous. The Ti-PLM showed a desorption capacity of 28-30% for As. The results suggest that the Ti-PLM can be used for the removal of As ions.Ninety-six Duroc × Landrace ×Yorkshine pigs with an average initial body weight of 30.6 ±1.35 kg were randomly allotted to two supplementation of arsenic (0 and 30.0mg/kg) (as As2O3) and two levels of Ti-PLM (0 and 0.2%) in a 2×2 factorial arrangement of treatments. Each of groups was consisted of three pens (replications) of eight pigs and was fed corn-soybean basal diets. The content of arsenic in basal diets was 0.38 mg/kg. The trial lasted for seventy-eight days after seven days of adaptation period. At the end of the feeding trial, two animals (one barrow and one gilt) from each pen were randomly slaughtered. The samples of serum and tissues were collected for analysis. The results were showed as follows:Arsenic significantly decreased average daily gain (ADG) and feed conversion ratio of pigs, impaired antioxidant system and immune competence, injured organ function, increased arsenic residules in tissues, and altered trace mineral retentions. No siginificant differences in growth performance and all related parameterswere found between the control and pigs fed Ti-PLM alone, indicating that Ti-PLM was inert and nontoxic and can be added in diet safely as a feed additive.The addition of 0.2% Ti-PLM to arsenic-contaminated diet significantly decreased arsenic levels in tissues of pigs and markedly increased arsenic excretion in the feces, suggesting that Ti-PLM adsorped arsenic in gastrointestinal tract and formed a stable complex, which can not be absorped and excreted in feces.The addition of 0.2% Ti-PLM to arsenic-contaminated diet alleviated the effects of excess arsenic on growth performance, antioxidant system and immune competence, organ function and trace mineral retentions. These finding indicated that Ti-PLM can effectively diminish the deleterious effects of arsenic on pigs.The results showed that as a non-nutritive absorptive material, Ti-PLM could effectively reduce arsenic absorption in gastrointestinal tract by its specific adsorption, which offered an inspiriting solution to reduce arsenic residues in animal products.
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