Horses that live only on diets of pasture and hay generally aren't susceptible to acid-alkaline imbalances. It has long been thought that the inclusion of processed grains, which can contribute to an acid-alkaline imbalance, is modified by pasture grasses and hay. The alkaline nature of the forages keeps the blood Ph balanced. So even horses with limited turnout, on plenty of hay, fed commercial grains, in theory would not suffer from acid-alkaline challenges.
If we look at grains from the perspective of the acid-alkaline balance, virtually all unsprouted grains are considered acid to the blood Ph. However, sprouted grains are alkaline.
Before the advent of corporate farming, and high speed milling, farmers cut their grain crops and left them overnight or for a day or two before harvesting. This method exposed the grain seeds to dew; water being a key component in the sprouting process. The dew broke the phytic acid (a seed's natural protection barrier) thus taking the seed from it's "sleep state" to it's "awaking state". When the grains were taken to the mills, the seeds were not exposed to high heat processing, thus ensuring the nutrients and enzymes stayed intact. The seeds were not de-natured.
What we don't know from any formative study on commercial feeds is what effect the added molasses, and the synthetic fortified nutrients combined with the highly processed grains have on the acid-alkaline balance.
We do know that pharmaceutical medications are predominately acidic to the blood Ph. In theory the forage diet would compensate for the added acidity of the meds. But if we compound this with other factors: herbicide and pesticide usage,
acid rain in regions without a limestone base, the added feeding of synthetic supplement formulas, the daily rations of commercial feed, the lack of variety of plants, herbs, native grasses, and fruits in most sport horses' diets, and the added effect of pollution ----we could be tipping the balance towards immune system challenges, and ultimately a blood Ph that becomes a host for viruses.
Horses in work and training need alkaline reserves to maintain their blood Ph balance. A study in Australia by Ranvet (www.ranvet.com.au/acidosis.htm) on acidosis in race horses highlights this need for alkalis to balance the acids. The study points out that poor performance, and sourness may be the result of low alkaline reserves.
Equine allergies, ulcers, and metabolic challenges may be related to the acid-alkaline balance. The steep rise in these health issues and the concurrent rise in the corresponding human imbalances (allergies, digestion, diabetes) cannot be easily dismissed as coincidence.