Gluconeogenesis from caecal propionate in the horse.

This research study investigates how the horse’s cecum produces propionate, a substance involved in energy production, using two Shetland-type ponies as their test subjects. They found that the rate of propionate production and its contribution to overall glucose production remained constant, regardless of changes in the horses’ diet.

Research Methodology

• The researchers experimented on two Shetland-type ponies who were fitted with caecal and colonic cannulas – tubes inserted into the body to drain or administer fluid.
• The ponies were fed two types of diets: one with hay only and the other combined with wheat bran.
• The researchers measured the production of propionate in the cecum of the horse by infusing the cecum with 14C-labelled sodium propionate. This allowed them to trace and measure the production and utilization of propionate in the body.
• Simultaneously, a [2-3H]glucose infusion was used to measure total glucose entry into the bloodstream.

Results and Findings

• They found the average cecal propionate production was 19.6 mg/h per kg body weight with a hay diet and 34.0 mg/h per kg body weight with a hay and wheat bran diet. The energy provided by these diets was 177 kJ/kg and 187 kJ/kg body-weight per d, respectively.
• The mean total glucose production (mg/h per kg body-weight) in one pony was 104 and in the other 135. Importantly, these rates remained constant, unaffected by the type of diet the ponies were on.
• Remarkably, they found that about 7% of the total glucose production was derived from propionate produced in the cecum. This percentage remained consistent, regardless of changes in diet or differences between individual animals.

Conclusion

• This research expands our understanding of how horses metabolize food and produce energy. They found that regardless of diet, propionate production from the cecum and its contribution to total glucose production remained consistent.
• These findings could potentially contribute to improved dietary management strategies for horses, ensuring their health and energy levels are effectively maintained.