Big Head
Tracy Soward-Amalfi: Equine Nutritionist
Calcium is of one the most important minerals required in the horses diet to maintain strong, healthy bones and teeth and to aid muscle and nerve function. It is essential that a horse’s diet is balanced and maintains a calcium phosphorus ratio of 2:1 to maintain good health and nutrition. However there are times in which this vital mineral is prevented from being absorbed adequately within the horses’ body therefore creating serious physiological problems.
The major nutritional problem facing horse owners is ‘Big Head” disease or nutritional hyperparathyroidism. Clinical signs of big head may include lameness, ill thrift; lose of body condition and swollen jaw bones. The disease can develop within two months of placing horses onto affected feeds but more often it can take six to eight months. This is a serious condition and if left untreated can result in death.
Big head occurs when there is a calcium imbalance within the horses’ diet. This is often the result of horses being kept on tropical and sub- tropical grass pastures such as buffel grass, pangola grass, para grass, and kikuyu and seteria grass. These grasses are high in a naturally occurring compound called oxalic acid which prevents adequate absorption of calcium. Once calcium becomes bound by oxalic acid it forms oxalates which do not allow the absorption of calcium in the small intestine. Calcium bound by oxalate then travels to the large intestine where the fermentation process releases limited amounts of calcium. This limited calcium absorption results in a lowering of blood calcium levels. In response the horses’ body activates the parathyroid gland to release parathyroid hormone. The function of this hormone is to reabsorb calcium from within the body and to restore adequate blood calcium levels. Calcium is reabsorbed primarily from the facial and pelvic bones and eventually from long bones. The reabsorption of calcium from these areas often results in chronic demineralisation of facial bones which causes the "big head" appearance.
Horses can also develop big head if their diets contain wheat bran and pollard products. These diet components are high in calcium phytate which act in a similar manner to oxalate and not only bind calcium but also bind phosphorus in the process. Restoring the correct balance of calcium and phosphorous within the horses blood stream is imperative in the treatment and prevention of big head disease. Traditional treatments of big head have required the mixing of many different compounds which is time consuming, messy, confusing and in the majority of cases not very palatable to the horse. Today however, the treatment and prevention of big head has been simplified by the introduction of Hyfeed Big Head pellets around four years ago.
Hyfeed is a Queensland company based in Toowoomba and in conjunction with the Queensland Equine Nutrition Centre have developed Big Head pellets the only product on the market specifically targeted to aid in the treatment and prevention of big head disease symptoms.
Big Head pellets combat the effects of big head disease by helping to restore calcium levels within the blood. Containing a 3:1 calcium phosphorus ratio feeding Big Head pellets ensures that maximum calcium absorption occurs. Big Head pellets are suitable for all horses on problem pastures or feeds and can be used as a preventative or treatment of big head disease symptoms. In addition Big Head pellets act as a supplementary energy source and contain essential vitamins and trace minerals to aid the horse during the recovery process.
It may not be possible to remove horses from problem pastures but now, thanks to Hyfeed and Big Head pellets it is possible to manage horses at risk of big head disease without complication and with confidence.
Feeding Recommendations
Note: This supplement can also be used as an energy source for working horses.
If you have any further questions please feel free to visit our website www.hyfeed.com.au or contact us on 07 46 332266.