Why Calcium Balance Matters on Oxalate Pastures

Australian research by Dr Jennifer Stewart, Dr Oliver Liyou and Dr Margaret Wilkinson

Jenquine Bone Formula Forte® and Calsorb Forte® are underpinned by Australian research investigating calcium metabolism in horses grazing oxalate‑containing pastures. This research was conducted by Dr Jennifer Stewart, Dr Oliver Liyou, and Dr Margaret Wilkinson and examined serum parathyroid hormone (PTH) levels, faecal calcium excretion, and overall calcium balance in horses grazing oxalate‑containing grasses under real‑world conditions.

The findings demonstrated that horses grazing these pastures frequently exhibit elevated PTH levels and increased calcium loss, even when serum calcium values remain within the normal reference range. The research highlighted that calcium imbalance on oxalate pastures is often sub‑clinical, that blood calcium alone is an unreliable indicator of whole-body calcium status, and that effective nutritional support must prioritise bioavailability and utilisation, not just intake.

Why lucerne and standard supplements may not be enough

A key finding from the research was that horses grazing oxalate pastures still showed elevated PTH levels even when fed lucerne and common calcium supplements.

This highlights an important point:

🔹 Not all calcium sources are equally effective in oxalate‑rich diets.

The form of calcium, its bioavailability, and how it is delivered all matter.

Simply adding more calcium does not guarantee that the horse can absorb and utilise it effectively.

Jenquine’s evidence‑based approach to calcium nutrition

Jenquine Bone Formula Forte® and Calsorb Forte® were developed in response to this research and the realities of Australian grazing conditions.

Our approach focuses on:

🔹 Highly bioavailable calcium sources

🔹 Supporting calcium utilisation, not just intake

🔹 Correct mineral balance to avoid further interference with calcium absorption

🔹 Practical solutions for horses grazing high-oxalate pastures

Download the research

‘Serum parathyroid hormone and faecal calcium levels in horses on oxalate‑containing grasses.’
Jennifer Stewart, Oliver Liyou and Margaret Wilkinson.
Bain Fallon Conference Poster, 2010

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Real Horses. Real Results.

  • Side-by-side photos showing a horse's head before and after magnesium supplementation.

    “Jenquine Bone Formula is a lifesaver to my mare. She got big head after a lot of rain and fresh buffalo came through. Within weeks her face blew up and within 3 months on Bone Formula it reduced by 50% So grateful for this product!”

    ~ Selina Robinson