Soluble corn fiber, resistant corn starch, and protected butyrate effects on performance, gastrointestinal volatile fatty acids, and apparent total-tract digestibility of calcium and phosphorus in nursery pigs

Authors: Kerr, Brian; Pearce, Sarah; RAMIREZ, SHELBY - Dsm Nutritional Products, Ltd; SCHWEER, WESLEY - Zinpro Corporation; GABLER, NICHOLAS - Iowa State University

Submitted to: Journal of Animal Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/11/2023
Publication Date: 3/1/2023
Citation: Kerr, B.J., Pearce, S.C., Ramirez, S.M., Schweer, W.P., Gabler, N.K. 2023. Soluble corn fiber, resistant corn starch, and protected butyrate effects on performance, gastrointestinal volatile fatty acids, and apparent total-tract digestibility of calcium and phosphorus in nursery pigs. Journal of Animal Science. 101. Article skad022. https://doi.org/10.1093/jas/skad022.
DOI: https://doi.org/10.1093/jas/skad022

Interpretive Summary: Calcium is a major component of the skeleton in addition to being essential for growth and is imperative for bone mass development. Improvement in calcium absorption in calcium-deficient diets has been shown in human and rodent studies when nondigestible oligosaccharides have been consumed due to a modification of gastrointestinal conditions which increase mineral solubility. Because swine have been shown to be an excellent model for human nutrition research, an experiment was conducted to determine how a moderately calcium-deficient diet would affect gastrointestinal fermentation conditions, calcium and phosphorus digestibility, bone mineralization, and growth performance in nursery pigs; and if supplementation of nondigestible oligosaccharides would affect these same parameters. Results of this study indicate that feeding young pigs a diet below recommended levels of calcium reduced colonic pH, increased apparent total tract digestibility of calcium and phosphorus, but had no impact on bone mineralization or overall pig performance. This information showing that supplementation of nondigestible oligosaccharides to calcium-deficienct diets has inconsistent effects on colonic pH, and does not affect calcium or phosphorus digestibility, bone mineralization, or overall pig performance; is important for nutritionists at universities, feed companies, pig production facilities, and human-related nutritionists on their approach to calcium nutrition and nondigestible oligosaccharide supplementation.

Technical Abstract: An experiment was conducted to determine how feeding a calcium (Ca) deficient diet would affect gastrointestinal pH and volatile fatty acids (VFA), Ca digestibility, bone mineral density (BMD), and performance in nursery pigs; and if supplementation of nondigestible oligosaccharides would affect these same parameters. Two hundred and forty weaned pigs (BW = 7.1 kg) were placed into 80 pens with 3 pigs/pen. The 8 dietary treatments consisted of: 1) positive control (PC, 0.83% total Ca), 2) negative control (NC, 0.50% total Ca), 3 and 4) NC + 5% or 7.5% soluble corn fiber (SCF), 5 and 6) NC + 5% or 7.5% resistant corn starch (rCS), 7 and 8) NC + 0.25% or 0.50% fat-protected butyrate (pBRT). Pigs were fed the dietary treatments for 21 d to determine average daily gain (ADG), average daily feed intake (ADFI) and gain:feed ratio (GF) with a fecal sample collected from each pen from each pen to determine Ca digestibility, with 1 pig/pen euthanized on d 21 for collection of ileal and colon contents and the left humerus. Pigs fed the NC diet had a lower colonic pH compared to pigs fed the PC (P = 0.06) but no effect on total VFA was observed (P > 0.10). Pigs fed diets containing SCF and rCS had a lower colonic pH and total VFA compared to pigs fed the NC diet (P = 0.05). Pigs fed diets containing pBRT had greater colonic total VFA compared to pigs fed the NC diet (P = 0.07), but no difference in colonic pH was observed (P > 0.10). Pigs fed the NC diet had a greater Ca digestibility compared to pigs fed the PC (P = 0.01), with no treatment to the NC having any effect on Ca digestibility compared to pigs fed the NC (P > 0.10). There was no effect of dietary Ca level on BMD and no overall addition of feeding SCF, rCS, or pBRT on BMD compared to pigs fed the NC (P > 0.10). There was no impact on pig ADG, ADFI, or GF by reducing dietary Ca by 40% (i.e., pigs fed the NC) compared to pigs fed the PC (P > 0.10). Relative to pigs fed the NC, there was no overall effect of SCF, rCS, or pBRT on ADG, ADFI, or GF (P > 0.10). In conclusion, feeding young pigs a Ca-deficient diet reduced colonic pH, increased digestibility of Ca, but had no impact on bone mineralization or overall pig performance. Supplementation of nondigestible oligosaccharides to Ca-deficient diets had inconsistent effects on colonic pH, and did not affect Ca digestibility, bone mineralization, or overall pig performance.