Effects of Biotite V supplementation on growth performance and the immunological responses of weaned pigs after an Escherichia coli lipopolysaccharide challenge

This study evaluated the effect of an aluminosilicate mineral additive-Biotite V (BV) on growth performance, the immunological and adrenal responses in weaned pigs after Escherichia coli lipopolysaccharide (LPS) challenge. Thirty-two crossbred weaned pigs were used in this 2×2 factorial experiment, with dietary treatment (basal diet with or without 0.45% BV supplementation) and LPS challenge (challenged or not challenged) as two main factors. On day 14 and 21, pigs were injected intraperitoneally with either 100 μg/kg body weight of LPS or an equivalent amount of sterile saline. Blood samples were collected 3 h after the first challenge followed by total and differential leukocyte counts and analysis of plasma tumor necrosis factor-α (TNF-α), prostaglandin E2 (PGE2), cortisol, insulin, and biochemical parameters. Body weight and feed intake were measured weekly throughout the 4-week experiment. The results showed that both LPS challenges reduced average daily gain (ADG) (P<0.05) and increased feed/gain (P<0.001), and BV decreased feed/gain (P<0.05) of immunology challenged pigs. The LPS challenge×diet interactions were observed for ADG (P<0.05) and feed/gain (P<0.05) during both challenge. LPS challenge reduced the number of white blood cells, lymphocytes, monocytes, and neutrophils (P<0.05). LPS challenge×diet interaction was observed for plasma TNF-α (P<0.05) concentration, showing decreased plasma TNF-α response to LPS challenged in pigs receiving BV. But no LPS challenge × diet interaction was observed for plasma cortisol or PGE2. There was a diet effect for plasma insulin (P<0.05) and glucose (P<0.05), showing increased plasma insulin and decreased glucose with BV supplementation, but no LPS challenge×diet interaction was observed. We conclude that BV improved the weight gain and feed efficiency of weaned pigs during an immunological challenge by suppressing the proinflammatory cytokine release.