Horses fed a diet of only forage have greater bacterial stability and fewer "bad" fecal bacteria, such as Streptococcus spp, than horses that are also fed concentrates. This finding, reported by a group of Swedish researchers, provides opportunities for the industry to develop more targeted feeding strategies to support equine health and welfare.

"Diets rich in readily fermentable carbohydrates, fed traditionally to meet the increased energy requirements of the performance horse, are associated with a number of gastrointestinal disorders that involve disturbances in the intestinal microbiota," wrote the research team, led by Professor Jan Erik Lindberg from the Department of Animal Science at the Swedish University of Agricultural Science.

In this preliminary study, researchers examined the impact of feeding a high-energy forage-only diet or a more traditional forage-concentrate diet on fecal microorganisms.

Lindberg and colleagues fed six mature Standardbred geldings in training either the forage-only or the forage-concentrate diets for 29 days. They extracted and analyzed bacterial DNA four times during the study period, measuring fecal pH and culturing bacteria on the last day