Stallion owners often wonder if they can feed something to improve fertility or libido (desire to breed).  A tremendous amount of misinformation exists regarding the nutrient requirements of stallions and the potential benefits of various magic potions that claim to improve reproductive performance.  In reality, feeding nutrients beyond those that are necessary to balance the stallion’s diet will not improve fertility or libido.  Further, nutrition research has not supported super fortification of a stallion’s diet with any single nutrient as a means of improving male reproductive performance. 

The best approach for properly feeding a breeding stallion is to consider his nutritional requirements to be similar to those of a performance horse.  With breeding stallions, as with performance horses, the most critical dietary factor is energy (calories).  The amount of calories a stallion consumes per day can have dramatic effects on overall health.  Too many calories will cause the stallion to become obese.  Obesity is thought to decrease libido and cause a multitude of health problems.  In addition to possible weight loss, too few calories may cause stallions to tire easily or be reluctant to breed.  Therefore, monitoring body condition (fatness or thinness) in breeding stallions is the first step to ensuring proper nutrition.  Feeding high-quality hay and a “balanced” concentrate for performance horses will typically supply enough nutrients to satisfy the requirements of male reproduction.  If grain is not needed, a low-intake, low-calorie supplement rich in protein, vitamins, and minerals is necessary to provide nutrients that may be marginal in all-forage diets