- 1). Begin feeding your horse spirulina a smaller amount per day than the recommended dose so your horse's digestion can adjust to the new food. Since the daily recommended dose of spirulina is 40 grams (or 1/4 ounces) per 1,000 pounds of horse, split the dosage between two separate feedings (20 grams or 0.7 ounces in the morning and in the evening) and begin with a 10 gram (0.4 ounce) dose twice daily.
- 2). Increase your horse's dosage gradually to 20 grams of spirulina per day during morning and evening feed time. Continue dosage for one to two weeks.
- 3). Examine your horse for signs that the spirulina is working, such as an increase in appetite, relief from hives and other allergies, and relief from heaves -- breathing problems in horses. Spirulina also is given to horses to help relieve anxiety, improve attitude and training ability. Look for changes in behavior if giving your horse spirulina for these reasons.