Journal of animal physiology and animal nutrition2008; 92(2); 173-181; doi: 10.1111/j.1439-0396.2007.00724.x

Mineral balance in horses fed two supplemental silicon sources.

Abstract: Numerous studies suggest that silicon (Si) supplementation is beneficial for mineral metabolism and bone health. Mineral balance studies have not been performed in horses to determine how these supplements affect absorption of other minerals. The purpose of these studies was to investigate the effects of two different Si supplements on mineral absorption and retention in horses. Eight geldings were randomly placed in one of two groups: control (CO) or supplemental Si, which was provided by one of two supplements. The first, sodium aluminium silicate (SA), contains a bioavailable form of Si and is high in aluminium (Al). The second supplement contains oligomeric orthosilicic acid (OSA). All horses received textured feed and ad libitum access to hay. Supplemented horses received either 200 g of SA or 28.6 ml of OSA per day. Following a 10-day adaptation period, the horses underwent a 3-day total collection. Blood samples were taken on days 0 and 13. The two balance studies were conducted 4 months apart to reduce carryover effects. Intakes of Al and Si were greater with SA supplementation (p < 0.05). Sodium aluminium silicate increased faecal and urinary Si excretion (p < 0.05). Calcium retention and apparent digestion were increased by SA (p < 0.05). It also maintained plasma Si compared with the CO which tended to have a decrease in plasma Si (p = 0.08). Supplemental OSA increased retention of Ca and B (p < 0.05) and apparent digestion of B (p < 0.01). Orthosilicic acid tended to increase Si retention (p = 0.054), apparent digestion (p < 0.065), and also increased plasma Si. Both supplements were able to alter Ca retention and B metabolism, however, only OSA was able to alter Si retention, digestibility and plasma concentration. Orthosilicic acid, an Si supplement without substantial Al, appears to be a viable option for Si supplementation as it increased Si retention and digestibility.
Publication Date: 2008-03-14 PubMed ID: 18336414DOI: 10.1111/j.1439-0396.2007.00724.xGoogle Scholar: Lookup
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The research article studies the effects of silicon (Si) supplementation on the absorption and retention of minerals in horses. The two supplements being tested are sodium aluminium silicate (SA) and orthosilicic acid (OSA).

Research Objectives

  • The research aimed to explore the impacts of two different silicon supplements on the absorption and retention of minerals in horses.
  • While past studies suggest that silicon supplements could impact mineral metabolism and bone health, this study specifically looks at the effects in horses, a field where studies have previously been unperformed.


  • Eight geldings (a type of male horse) were randomly placed into control (no silicon supplement) and supplemental Silicon groups.
  • The silicon in the study group was provided either by Sodium aluminium silicate or oligomeric orthosilicic acid.
  • For accuracy, the study was conducted twice, with a gap of 4 months to decrease the chances of carryover effects.
  • Horses received specified feeds and supplements, post which their mineral absorption and retention were monitored and studied over periods of time.

Key Findings

  • It was observed that the intake of Aluminium (Al) and Silicon were greater with Sodium aluminium silicate supplementation, which also led to an increase in fecal and urinary silicon excretion.
  • Sodium aluminium silicate influenced calcium retention and apparent digestion positively and helped maintain plasma silicon levels.
  • Orthosilicic acid, on the other hand, increased the retention of the minerals calcium and boron (B), as well as the apparent digestion of boron.
  • Orthosilicic acid also showed a trend of increasing silicon retention, digestion, and boosted plasma Silicon concentration.


  • Both supplements altered calcium retention and boron metabolism. However, only Orthosilicic acid was able to impact silicon retention, digestion, and plasma concentration.
  • Orthosilicic acid, being a silicon supplement without substantial Aluminium, appears to be a viable option for silicon supplementation as it showed increased silicon retention and digestibility.

Cite This Article

O'Connor CI, Nielsen BD, Woodward AD, Spooner HS, Ventura BA, Turner KK. (2008). Mineral balance in horses fed two supplemental silicon sources. J Anim Physiol Anim Nutr (Berl), 92(2), 173-181.


ISSN: 1439-0396
NlmUniqueID: 101126979
Country: Germany
Language: English
Volume: 92
Issue: 2
Pages: 173-181

Researcher Affiliations

O'Connor, C I
  • Department of Animal Science, Michigan State University, East Lansing, MI, USA.
Nielsen, B D
    Woodward, A D
      Spooner, H S
        Ventura, B A
          Turner, K K

            MeSH Terms

            • Animal Feed
            • Animal Nutritional Physiological Phenomena
            • Animals
            • Biological Availability
            • Bone and Bones / chemistry
            • Bone and Bones / metabolism
            • Cross-Over Studies
            • Dietary Supplements
            • Digestion
            • Horses / blood
            • Horses / metabolism
            • Horses / urine
            • Intestinal Absorption / drug effects
            • Male
            • Minerals / pharmacokinetics
            • Random Allocation
            • Silicic Acid
            • Silicon / metabolism
            • Silicon / pharmacology


            This article has been cited 5 times.
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            2. Main SC, Brown LP, Melvin KR, Campagna SR, Voy BH, Castro HF, Strickland LG, Hines MT, Jacobs RD, Gordon ME, Ivey JLZ. Metabolomic Profiles in Starved Light Breed Horses during the Refeeding Process.. Animals (Basel) 2022 Sep 21;12(19).
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            3. Pritchard A, Robison C, Nguyen T, Nielsen BD. Silicon supplementation affects mineral metabolism but not bone density or strength in male broilers.. PLoS One 2020;15(12):e0243007.
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            4. Pritchard A, Nielsen BD, Robison C, Manfredi JM. Low dietary silicon supplementation may not affect bone and cartilage in mature, sedentary horses.. J Anim Sci 2020 Dec 1;98(12).
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            5. Jurkiu0107 LM, Cepanec I, Paveliu0107 SK, Paveliu0107 K. Biological and therapeutic effects of ortho-silicic acid and some ortho-silicic acid-releasing compounds: New perspectives for therapy.. Nutr Metab (Lond) 2013 Jan 8;10(1):2.
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