Feeding Grass Hay Before Concentrate Mitigates the Effect of Grain-Based Concentrates on Postprandial Plasma Interleukin-1β.

The research article is about a study that explored the benefits of feeding horses with grass hay prior to giving them a starch-rich diet. It found that this practice resulted in lower levels of plasma interleukin-1β (IL-1β), an inflammatory marker, after meals and also curbed a rapid fermentation of starch and sugars in horses’ digestive tracts.

Objective of the Research

• The key objective was to investigate the influence of feeding grass hay to horses before feeding them concentrated feed (rich in starch) on the subsequent increase in interleukin-1β (IL-1β). A high level of IL-1β is an indicator of bodily inflammation.
• The researchers hypothesized that pre-feeding grass hay might regulate the digestive process to prevent a rapid fermentation of starches and sugars, thereby controlling the rise of IL-1β levels in the blood.

Research Methodology

• Six mature geldings (neutered male horses) were used for the study and were recruited under a switchback design, where the same subjects could be used under different conditions for comparison.
• Horses were fasted overnight and then offered a concentrated feed that had 1.2 g/kg bodyweight of nonstructural carbohydrates.
• The plasma (a component of blood) of these horses was collected at various intervals (30 minutes before giving hay and 1, 2, 4, 6, and 8 hours after the feed) to measure IL-1β and d-lactate levels.

Findings of the Study

• According to the findings, feeding grass hay to horses before providing a concentrated meal reduced the post-meal IL-1β concentrations at all measurement points compared to control horses (who were not pre-fed grass hay).
• Additionally, the study detected a correlation between the time hour and the treatment with regards to mean d-lactate concentrations, with the hay-first fed horses exhibiting lower d-lactate concentrations at post-feeding hours 1, 2, and 4 in comparison to control horses. This is significant as a high level of d-lactate is a sign of abnormal metabolism.

Conclusion

• The study concluded that feeding a small quantity of hay before a high-starch meal helped in mitigating the adverse effects of quick starch and sugar fermentation in the equine digestive tract, as evidenced by reduced post-meal d-lactate and IL-1β levels.
• Though the study uncovered intriguing findings, future research may be required to understand long-term impacts, variation in different breeds, and optimum hay quantity.