Effect of dietary supplementation with long-chain n-3 fatty acids during late gestation and early lactation on mare and foal plasma fatty acid composition, milk fatty acid composition, and mare reproductive variables.

The research tests the impact of dietary marine-derived n-3 fatty acids on the composition of horse and foal plasma and milk was examined and it is found that dietary supplementation of certain fatty acids can have an effect on the reproductive cycles in mares and fatty acid composition in both the mothers and their offspring.

Research Outline

The researchers conducted an experiment with mares (female horses) to evaluate the effects of three different types of diet:

• The corn oil diet (CORN)
• The docosahexaenoic acid (DHA) diet
• The diet containing both eicosapentaenoic acid (EPA) and DHA

Methodology and Data Collection

These diets were assigned to the mares 60 days before their expected foaling dates. The researchers collected milk and plasma for analysis of fatty acids. They also recorded data about the size and growth of ovarian follicles after birth until the mares’ first post-birth ovulation. They also examined blood samples post-ovulation for a substance called prostaglandin F metabolite (PGFM), which is related to the ovulation process.

Results and Observations

Supplementation with DHA, either alone or with EPA, had several effects on the mares:

• It led the mares to have lower levels of a fatty acid known as linoleic acid in their plasma, and higher levels of EPA and DHA (compared to the corn oil diet).
• It resulted in higher levels of arachidonic acid and either DHA or EPA and DHA in the milk of the mares.
• It increased the levels of DHA or both EPA and DHA in foal plasma.

The research didn’t find any significant effect on the concentration of PGFM.

Effects on Reproduction

The study also discovered impacts on the mares’ reproductive cycles:

• The diet containing both EPA and DHA delayed the first ovulation after birth compared to the corn oil and the DHA diet.
• The period of follicular retention – a stage in the ovulation cycle – before ovulation was longer in mares on the EPA and DHA diet compared to the other two diets.

Conclusions

The article concludes that maternal dietary supplementation with EPA and DHA fatty acids can alter the fatty acid profile of milk and plasma in both mares and foals. It also suggests that these supplements may have the potential to delay ovulation in the early postpartum period.