# Free Plasma Amino Acid Concentrations in Horses Fed Different Dosing Regimens of Hydrolysed Collagen

## TL;DR

This study found that a 100 g/day dose of hydrolysed collagen in horses leads to higher plasma amino acid concentrations, which could be beneficial for health.

## Contribution

The study identifies the optimal dose of hydrolysed collagen for amino acid availability in horses.

## Key findings

- A 100 g/day dose of hydrolysed collagen increases plasma amino acid concentrations in horses.
- Amino acids from hydrolysed collagen remain detectable in plasma for at least 24 hours.
- Significant differences in amino acid levels were observed between the 100 g and control doses.

## Abstract

Dietary supplements containing hydrolysed collagen (HC) are used for the treatment of osteoarthritis and improvement of hoof horn growth in horses and more recently in the management of gastric ulcers in horses. The purpose of this study was to investigate the oral availability and determine the appropriate dose of a specific commercial equine dietary supplement containing HC, by measuring the free amino acid (AA) profiles in blood plasma. This study demonstrated the availability of the hydrolysed collagen of this specific dietary supplement and that 100 g/day resulted in higher plasma concentrations, which could be detected for at least 24 h, suggesting a potentially greater clinical relevance.

Hydrolysed collagen is used as a supplement for horses with osteoarthritis, hoof horn growth problems, and gastric ulcers. To determine the oral availability of a specific hydrolysed collagen supplement and the appropriate dose, six Warmblood mares were fed two different concentrations of the supplement: 100 g HC (CH), 50 g HC (CL), and a control of 0 g HC (CN) during one week in a randomised cross-over design. On day 7, 14 and 21, blood sampling for amino acid (AA) analysis was performed, just prior to feeding the supplement (t = 0) and every hour after feeding for 8 h (t = 1–8). Statistical analysis revealed differences in mean plasma AA concentrations between the CH and CN doses for alanine, arginine, glutamine, glycine, proline, serine and hydroxyproline. Similarly, statistical differences were observed between the CL and CN doses for arginine, glycine, proline and hydroxyproline. This study demonstrated the availability of amino acids from the supplemented hydrolysed collagen. Although clinical efficacy was not evaluated in this study, a dose of 100 g HC once daily resulted in higher plasma concentrations, which remained detectable for at least 24 h, suggesting greater clinical relevance.