Managing Cushing's Disease in the Competition Horse

Feed management of the competition horse with Cushing’s Disease

The main challenges for the competition horse with Cushing’s Disease are ensuring your horse has sufficient energy, strength and endurance to compete whilst reducing the risk of complications caused by Cushing’s Disease  (PPID).  Pergolide, the main medicine used to treat Cushings Disease is not permitted in competition and there is a need for a withdrawn period before competing – this makes managing the diet even more crucial.

 Managing a much increased risk of laminitis whilst feeding for competition: 

Managing the laminitis is achieved via a high fibre / very low starch and sugar diet. However very low starch and sugar diets have been associated with a drop in performance / top line  in high performance horses.

By low starch and sugar we are talking about 10-12% total starch and sugar in the overall diet.

This means:

• Feeding soaked hay rather than haylage. Haylage can be higher than 10% sugar; soaking hay reduces its soluble sugar content.  Soak for 6-12 hours – 12 hours can reduce the sugar by up to 50% but may not be practical in warm weather)
• Hard feed:
  • Feed several small meals to avoid any large peaks in glucose and insulin
  • There are few very low starch and sugar hard feeds, but they do exist.
  • Or: use a feed balancer – these are generally low in starch and sugar and are well supplemented with vitamins and minerals, but as your horse’s work intensity increases, or if he needs more condition, additional supplementation of energy would be required.
  • Supplementing Vitamin B12 before and after competition helps to increase energy levels.

Managing weight loss/muscle tone

A rich supply of amino acids from quality protein sources would help with this.  Standard commercially available conditioning feeds can be 20-30% starch and sugar so are best avoided.

Supporting the immune system

PPID results in increased circulating levels of the stress hormone cortisol.  This depresses the immune system (as well as increasing the risk of laminitis).  To provide extra support to the immune system, feeding high doses of antioxidants is recommended.  Vitamin E and Selenium supplements are the best known for this –  avoid any herb-based products in case of potential interactions with the Pergolide and any other medications the horse might be receiving.

Boosting the diet with Vitamin C is a useful respiratory supplement and will help support the immune system.