Effect of a supplementary dietary evening primrose oil mixture on hoof growth, hoof growth rate and hoof lipid fractions in horses: a controlled and blinded trial.

This study investigates the impact of an evening primrose oil mixture (EPOM) supplement on hoof growth, growth rate, and lipid content in horses. The researchers found no significant differences in hoof growth or growth rate between the supplemented group and the control group, but did observe changes in specific lipid concentrations within the hoof structure.

Research Methodology

• The research was carried out at the Defence Animal Centre using twelve horses. The horses were carefully matched by characteristics such as sex, age, weight, height, and color and then assigned randomly to a treatment group or a control group.
• The treatment group received 30 ml of evening primrose oil mixture per day as a supplement, while the control group did not. Apart from this, both groups were managed and fed in the same way.

Results and Findings

• The researchers did not observe any significant difference in terms of hoof growth or growth rate between the group of horses that received the supplement and the control group.
• However, within the treatment group, there was a notable difference in hoof growth between weeks 4 and 8 after the start of the supplementation process. This suggests that the supplement might have some impact on hoof growth, but the difference was not sufficient to distinguish it from the control group.
• In terms of lipid content, there were no observed significant differences between the treatment and control groups in the stratum medium (the middle layer of the hoof wall). This suggests that the supplement did not significantly alter the lipid profile of this part of the hoof.
• The lipid analysis did, however, reveal differences in the periople (outermost layer of the hoof). In the treatment group, cholesterol esters and partial glycerides increased, while free cholesterol decreased significantly after the supplementation. This indicates that the supplement does impact the lipid profile of the outermost layer of the hoof.

Conclusions

• The results suggest that supplementation with the evening primrose oil mixture does not have a significant impact on hoof growth or growth rate in horses, but it may affect the lipid profile in the outermost layer of the hoof wall.
• Additional research would be needed to investigate the biological implications of these altered lipid levels and to determine whether such an effect might have practical benefits or drawbacks for horse health and performance.