Liquid flow and capacity of the caecum and colon of the horse.

This study measures the rate of fluid flow from the caecum and large colon in ponies and found that the liquid flow rate was roughly 54.2 litres per day from the caecum and about 49.4 litres per day from the end of the dorsal colon. The capacities of the caecum and the large colon were found to be approximately 7 and 17.7 litres respectively.

Study Approach

• The experiment was conducted on four Shetland-type ponies who were on a hay diet. Using these ponies allowed for control over diet which is a known factor affecting fluid flow.
• The ponies were divided into two groups. In first group, the ponies had cannulas (a type of tube used to deliver or remove fluids) inserted in their caecum (part of the intestine) and the beginning of the right ventral colon. In the second group, the cannulas were placed at the origin of the right ventral colon and near the end of the right dorsal colon. This setup allowed to measure the fluid flow from different parts of the digestive system.

Measurement and Results

• A solution of chromium EDTA was continuously infused into the caecum of the ponies in the first group. Fluid samples were then collected from the cannula at the start of the right ventral colon. This helped to ascertain the rate of fluid move through this part of the equine digestive system.
• On average, the rate at which the liquid flowed from the caecum was found to be around 54.2 litres per day. The rate was determined based on four separate measurements, increasing the reliability of the data.
• Similarly, for ponies in the second group, the chromium EDTA solution was infused into the right ventral colon and samples were collected from the right dorsal colon. These ponies had a flow rate of about 49.4 litres per day towards the end of the dorsal colon.
• Post mortem analysis showed that the capacity of the caecum was approximately 7 litres and that of the large colon, which is a part of the large intestine, was around 17.7 litres.

Significance of the Study

• The study provides insights into the physiology of the equine digestive system, which is valuable for both veterinary practices and research.
• Understanding the fluid flow in horses can have important implications for nutrition, health management strategies and diagnosing digestive disorders in equines.