Horses have evolved as monogastric herbivores and in their natural environment would spend a large part of their day grazing, feeding on a little and often basis.
Today, our modern domesticated horses lead a very different lifestyle. Access to grazing is often limited and many horses may be stabled for a large proportion of the day. Many of these horses will also be exercised regularly or may be subject to an intensive breeding program.
They will usually be meal fed a diet that is high in starch, often with sub optimal levels of dietary fibre.
Regular travel and competition or racing adds to the significant stress that a regime of this type can place on the digestivbe system leaving many horses at risk of digestive disturbance ranging from gastric ulcers to scouring, colic and even laminitis.
Disruption to the fine balance of bacteria or microflora found within the digestive tract can also have a detrimental effect on the immune system as the gut represents the first line of defence against infection.
Even leisure horses are exposed to essential management procedures such as routine worming (anthelmintic treatment), antibiotic therapy and travel which can place under stress on the digestive tract and immune system.