Rumen Bacterial Community Responses to Three DHA Supplements: A Comparative In Vitro Study

Area of Science:

• Animal Science
• Microbiology
• Nutritional Science

Background:

• Docosahexaenoic acid (DHA) is crucial for animal health.
• Understanding DHA's fate during digestion and its impact on rumen microbiota is vital for livestock nutrition.
• In vitro models offer a controlled environment to study these effects.

Purpose of the Study:

• To investigate DHA loss from various supplements post-digestion (rumen and gastrointestinal).
• To assess the impact of DHA supplements on rumen bacterial number and composition.
• To identify specific bacterial taxa affected by DHA supplementation.

Main Methods:

• In vitro digestion model simulating rumen and gastrointestinal conditions.
• Analysis of DHA concentration and loss rates in different supplement forms (powder, oil).
• 16S rRNA gene sequencing to profile rumen bacterial community composition and diversity.

Main Results:

• Algal oil exhibited the highest DHA loss rate, though bioaccessibility was comparable across supplements.
• DHA supplements significantly altered rumen bacterial composition, affecting key phyla, families, and genera.
• Algal oil notably reduced rumen microbiota richness and diversity, altering multiple important taxa.

Conclusions:

• DHA supplementation impacts rumen microbial ecology, with potential implications for biohydrogenation.
• Algal oil demonstrates a pronounced effect on rumen microbiota structure and diversity.
• Further research is warranted to elucidate the functional consequences of these microbial shifts in ruminants.