Calcium + Phosphorus

HHIO doesn't include Calcium or Phosphorus in its formulations, as on average an adult horse will get what they require from forage and bucket feeds.  Calcium in particular can be provided in excessive amounts (forage, lucerne) and Phosphorus in low amounts unless feeding a lot of grain.  We don't include, as not all horses need the top up of Calcium and/or Phosphorus.  Those that do, can be simply and affordably supplement with a product called DCP - Dicalcium Phosphate which is easily sourced from your local farm or feed store.  You can supplement this more economically than us adding it into the formulas, increasing the dose rate and therefore cost. 

The ratio that they are consumed in the diet is also important.  We utilise the base feed to address this ratio.  

IF you are following the HHIO feed protocol the base calcium and phosphorus needs will typically be met within the inclusions in your hard feed.  On the odd occassion and depending on your particular forage make up and especially active growing grass in spring, you may need to supplement if your horse starts seeking extra by eating dirt, stripping bark off trees etc. 

Calcium

For example, lucerne chaff (we love the balanced use of lucerne) is high in Calcium and is the most highly absorbable form of calcium for horses to consume. 

Phosphorus

Copra, rice bran and linseed (crushed or flax flake/pellets) are all higher in phosphorus. Which fed together will provide Ca:P.

 Sourcing DCP:

We no longer offer DCP for purchase but you can source 20kg bags from your local farm store (Farmsource, Farmlands, PGG Wrighstons) which is the most economical option especially for larger numbers.  For one horse the Feed Central product may work better.

Typical analysis of DCP is: 10 grams:  2.2g calcium / 1.8g phosphorus

Dose Rate 20 - 100g depending on needs & size of animal

A 25ml scoop = 20g

Testing of your forage is the accurate way to know what intake your horses need.  However as a general minimum base guide we suggest 20g dose daily for Broodmares in foal, and weaned young stock up to around 5 years of age.  For Last trimester and lactating Broodmares suggest 40g-60g dose rate.  Based on a 500kg weight.

Stockists:

Farmsource

Feed Central - This is Harvest grains DCP product

DancaPhos - Nutritech product which also includes Vitamin A & D, which is safe to use alongside HHIO products.

A bit about Calcium & Phosphorus supplementation

The peak times that Calcium and Phosphorus are needed is 3^rd trimester and lactating and actively growing stock.  ISome horses when the grass is actively growing and presents as eating bark, dirt, may also require supplementation. Phosphorus needs the phytase enzyme to break it down to be able to be digested in the horses’ digestive tracts.  Phytase is produced in the hindgut microbes, so when that gets upset with the less dry matter, it perhaps upsets this balance.

General Ca:P supplementation does however depend largely on what is going in forage wise as a lot of forage provides ample calcium and can be on the lower phosphorus side.  More calcium is not always better.  Forage analysis is always a good base, if possible. Interestingly Calcium also has interactions with Iron and can negatively impact Zinc and Manganese levels if too high which can be a common occurance with the prevelant of added calcium in feeds and calcium naturally incurring in feeds such as Lucerne.

But it all comes down to the ratios.  Horses (including breeding and youngstock) generally need a 1.5-2:1 Ca : P ratio but can cope with up to 6:1 ratio as long as the minimum need for phosphorus is met (eg: 14g for a 500kg horse at maintenance vs 20g Calcium – daily).  Phosphorus is present in grains and forage (oxalates) which can bind out calcium.  If calcium is too high vs Phosphorus it will grab it from bone and balance and same for if Phosphorus is too high vs Calcium.  A 1:1 ratio is bare minimum and 0.75:1 is problematic. 

Our basic HHIO tried and true base combo of lucerne chaff + copra or rice bran offers both highly absorbable forms of calcium (lucerne) and phosphorus (copra/rice bran and also flax/linseed).  Prefer to utilise the bucket feed to cover this and in a form that horses will absorb easily.  DCP is a good option when you don’t know what your levels are and to ensure basic needs are met.  Even offering a slab of lucerne hay would cover extra calcium (and protein/caloric) needs.  You could absolutely use this approach to top up the calcium and phosphorus levels. Rice Bran in particular is a very high source of phosphorus – but must not be over fed generally suggest max of 500g-1kg per day, alongside a slab or two of lucerne hay.  This approach is balanced to the Foundation or Performance formulas.