Effect of dietary medium chain triacylglycerols on plasma triacylglycerol levels in horses.

This research project aimed to establish if feeding horses medium chain triacylglycerols (MCT) would increase plasma triacylglycerol levels by enhancing the availability of glucose for fat creation. Findings demonstrated feeding horses MCT versus soybean oil did increase plasma triacylglycerol levels, however, no significant impacts were observed from the source of carbohydrates in the diets.

Research Method

This study followed a Latin Square experimental design, involving four horses and four different dietary treatments. Each experimental period lasted for 21 days. Blood samples were taken from the horses 16 hours after feeding. The diets were made up of hay and experimental concentrates which varied in fat source (either MCT or soybean oil) and carbohydrate source (either corn starch plus glucose or cellulose).

• The dietary variables, either MCT or soybean oil, accounted for around 27% of the total dietary net energy.
• The carbohydrate sources, either glucose plus corn starch or cellulose, provided 33%.

Findings

The study found that feeding MCT instead of soybean oil raised the plasma triacylglycerol levels significantly. However, results also showed that the source of carbohydrates in the diets had no significant effect. There was also no observed impact regarding the interaction between fat and carbohydrates. As a result, the initial hypothesis of the study was rejected.

Specific Results

• Feeding horses a diet containing soybean oil paired with cellulose instead of starch plus glucose produced a greater increase in plasma triacylglycerols.
• This carbohydrate effect was not observed when horses were fed MCT diets.

The researchers found that the experimental concentrates did not significantly impact the levels of other elements in the horses’ blood such as glucose, total serum cholesterol, phospholipids, insulin, and free fatty acids, as well as the activity of post-heparin lipoprotein lipase.

Potential Explanation for the Results

The researchers suggest that the MCT-induced increase in plasma triacylglycerols could be due to an increase in hepatic VLDL secretion, with additional substrate for increased synthesis of triacylglycerols coming from the acetyl-CoA derived from the hepatic oxidation of medium chain fatty acids.