Vitamin B2
Vitamin B2 (riboflavin) plays an important part in converting nutrients into energy, as it is a precursor of enzymes required for energy production from fats and amino acids. It is also involved in protein synthesis and influences growth. This is why vitamin B2 is colloquially known as the “growth vitamin”.
The normal requirement for a warmblood is between 20 and 25 mg per day. Vitamin B2 is found in high levels in yeast. As with other B vitamins, synthesis by the colon microbes is also assumed to occur.
However, if the horse has too little hay available, is fed poor-quality hay or suffers from chronic gut disorders such as watery droppings, microbial vitamin B2 synthesis may be reduced. For this reason, supplementing vitamin B2 is recommended. No harmful effects from vitamin B2 overdosing have been described in horses.