Omega-3 Sources for Dogs: Why We Use Marine Algae Instead of Fish Oil
Quick Answer
Marine algae provides the same omega-3 DHA benefits as fish oil for dogs while eliminating concerns about ocean contaminants and environmental impact. Fish obtain their omega-3s from eating algae, so using algae-derived DHA goes straight to the source.
Omega-3 Sources for Dogs: Why We Use Marine Algae Instead of Fish Oil
When formulating Petaluma's recipes, choosing the right source of omega-3 fatty acids was one of our most important nutritional decisions. While fish oil remains the most common omega-3 supplement in pet food, we chose marine microalgae as our DHA source. This wasn't just about creating a plant-based option—it was about providing the purest, most sustainable omega-3 nutrition available for dogs.
Understanding Omega-3 Fatty Acids for Dogs
Omega-3 fatty acids play crucial roles in canine health, from reducing inflammation to supporting brain function and cardiovascular health. [1] The omega-3 family includes three primary types:
- ALA (alpha-linolenic acid): Found in plant oils like flaxseed, chia seeds, and hemp
- EPA (eicosapentaenoic acid): Provides anti-inflammatory benefits and supports joint health
- DHA (docosahexaenoic acid): Essential for brain development, vision, and cardiovascular function
While dogs can theoretically convert ALA into EPA and DHA, this conversion is extremely limited and inefficient—typically less than 5% for EPA and under 1% for DHA. [2] This means dogs benefit most from preformed, long-chain omega-3s like DHA and EPA directly in their diet.
Why DHA Matters
DHA is particularly important for dogs throughout all life stages. Research demonstrates that DHA supplementation supports cognitive function, improves coat quality, maintains cardiovascular health, and helps resolve inflammation. [3] Growing puppies especially require DHA for proper neurological development and vision. [4]
The Original Source: Marine Microalgae
Here's a fact that surprises many people: fish don't produce omega-3 fatty acids themselves. Fish accumulate EPA and DHA by consuming marine microalgae and smaller organisms that eat algae. [5] Algae are the primary producers of these essential fatty acids in the ocean ecosystem.
When you use algae oil instead of fish oil, you're simply going directly to the source—skipping a step in the food chain. Marine microalgae, particularly species like Schizochytrium sp., naturally produce high concentrations of DHA through fermentation. [6]
Marine Algae vs. Fish Oil: The Research
Multiple peer-reviewed studies have evaluated algae-derived omega-3s in dogs, with compelling results. A recent study published in 2025 examined 24 Beagle dogs fed diets supplemented with either 1% fish oil, 1% algal powder, 1% algal oil, or no omega-3 supplementation for 28 days.
The results showed that algal-derived supplements significantly increased serum DHA levels—in fact, both algal powder and algal oil groups achieved higher DHA levels than the fish oil group. Dogs receiving algal supplements also showed improved coat quality and enhanced antioxidant capacity. [6] Importantly, no adverse liver effects were observed with algae-derived omega-3 supplementation.
Another long-term safety study examined algal oil containing EPA and DHA through gestation, lactation, and growth in Beagle dogs. The research confirmed that algae-derived omega-3s are safe and effective throughout all life stages. [7]
| Factor | Marine Algae Oil | Fish Oil |
|---|---|---|
| DHA Efficacy | Equal or superior serum DHA levels | Effective |
| Contaminant Risk | Minimal—grown on land in controlled conditions | Potential for mercury, PCBs if not purified |
| Sustainability | Highly sustainable—no fishing required | Depends on fishing practices |
| Bioavailability | High—contains triglyceride forms | Variable—may contain ethyl esters |
| Palatability | Neutral, no fishy odor | Often has strong fish smell |
| Oxidation/Rancidity | Controlled production reduces risk | Can oxidize if improperly stored |
The Purity Advantage
One significant advantage of algae oil is purity. Marine microalgae used in supplements are cultivated on land in large, controlled fermentation tanks. This cultivation process eliminates exposure to ocean-borne contaminants that can accumulate in fish, including:
- Mercury and other heavy metals
- Polychlorinated biphenyls (PCBs)
- Microplastics
- Other industrial pollutants
While high-quality fish oil supplements undergo purification processes to remove contaminants, a 2025 study analyzing fish oil supplements for dogs found detectable levels of arsenic in some products, though concentrations remained below safety thresholds. [8] Algae oil cultivation avoids these concerns entirely through controlled, land-based production.
Fish accumulate heavy metals through bioaccumulation—larger predatory fish that have lived longer contain higher concentrations of mercury and other toxins. [9] By sourcing omega-3s from algae rather than fish, we eliminate this contamination pathway while providing the same beneficial fatty acids.
Achieving the Right Omega Balance
The balance between omega-6 and omega-3 fatty acids matters for canine health. Omega-6 fatty acids (primarily linoleic acid) are essential for skin barrier function, immune response, and cellular processes. [10] However, omega-6s can promote inflammation when consumed in excess without adequate omega-3s to balance them.
Omega-3s, particularly EPA and DHA, work to resolve inflammation through specialized pro-resolving mediators called resolvins and protectins. [11] These compounds actively stop inflammatory processes and reduce tissue damage.
The National Research Council recommends omega-6 to omega-3 ratios between 2.6:1 and 26:1 for adult dogs, while AAFCO sets a maximum ratio of 30:1. [12] Research suggests that lower ratios—between 5:1 and 10:1—provide optimal anti-inflammatory benefits in dogs. [13]
How Petaluma Achieves Balance
At Petaluma, we carefully balance omega-6 and omega-3 fatty acids in our formulations. Our recipes include:
- Flaxseed: Provides ALA omega-3 fatty acids (though we don't rely on conversion to DHA)
- Marine microalgae: Delivers preformed DHA directly
- Peanut oil and sunflower oil: Supply essential linoleic acid (omega-6) for skin and coat health
We use high-quality, human-grade oils that are low in saturated fats and free from trans fats. By supplementing with algae-derived DHA while providing moderate omega-6 levels from quality plant oils, we achieve an optimal fatty acid profile that supports both essential functions and anti-inflammatory processes.
View our complete fatty acid profile and nutritional testing →
The Sustainability Factor
Beyond health benefits, choosing marine algae over fish oil represents a more sustainable approach to pet nutrition. Commercial fishing for fish oil has raised concerns about ocean ecosystem impacts and species depletion. Marine algae cultivation offers a different model:
- No fishing required: Algae is grown on land, eliminating pressure on wild fish populations
- Minimal waste: The cultivation process is nearly circular, with minimal environmental discharge
- Consistent quality: Controlled conditions ensure reliable DHA concentration and purity
- Smaller footprint: One kilogram of algal oil can replace up to 60 kilograms of wild-caught fish
As concern for ocean health grows, choosing ingredients that don't depend on marine extraction aligns with broader sustainability goals—without compromising nutritional quality for our dogs.
What About EPA?
You might notice that algae oil is particularly rich in DHA, while some fish oils provide more EPA. Does this matter? Research in humans and other mammals has shown that DHA supplementation can support EPA levels through metabolic pathways, [14] and a 2023 study comparing omega-3 sources in dogs found that marine long-chain omega-3s (both DHA and EPA) from sources like krill significantly improved omega-3 status better than short-chain plant sources. [2]
Additionally, DHA itself provides unique benefits that EPA cannot replicate, particularly for brain structure, vision, and cognitive function. [15] For most dogs consuming complete and balanced diets, adequate DHA supplementation from marine algae supports overall omega-3 status effectively.
Frequently Asked Questions
What is DHA and why do dogs need it?
DHA (docosahexaenoic acid) is a long-chain omega-3 fatty acid essential for brain development, vision, heart health, and reducing inflammation. [3] While not technically required to prevent deficiency, DHA is necessary to promote optimal health in dogs, particularly during growth and aging.
Is marine algae DHA as effective as fish oil for dogs?
Yes. Research shows algae-derived DHA significantly increases serum DHA levels in dogs, improves coat quality, and enhances antioxidant capacity—matching or exceeding fish oil supplementation. [6] A 2025 study found that dogs receiving algal supplements achieved higher DHA levels than those receiving equivalent amounts of fish oil.
Where do fish get their omega-3s?
Fish obtain their omega-3 fatty acids by consuming marine microalgae, which produce DHA and EPA directly through photosynthesis and fermentation. [5] Algae are the original source of these nutrients in the ocean food chain. Smaller fish eat algae, larger fish eat smaller fish, and omega-3s accumulate up the food chain.
Does fish oil contain heavy metals?
Fish oil can contain trace amounts of mercury, arsenic, PCBs, and other contaminants from ocean pollution. While high-quality fish oils undergo purification to reduce these contaminants, [8] algae oil cultivated on land in controlled conditions avoids ocean-borne contaminants entirely. Fish accumulate toxins through bioaccumulation over their lifespan.
Is algae oil more sustainable than fish oil?
Yes. Marine algae is grown on land in controlled fermentation tanks, requiring no fishing and generating minimal environmental impact. This cultivation method does not harm ocean ecosystems, does not contribute to overfishing, and uses a nearly circular production process with minimal waste. One kilogram of algal oil can replace up to 60 kilograms of wild-caught fish.
Can dogs with fish allergies eat foods with marine algae?
Marine microalgae are not fish and do not contain fish proteins. Dogs with fish allergies can typically consume algae-derived DHA safely, as it provides the omega-3 benefits without exposure to fish proteins. However, always consult with your veterinarian before making dietary changes for dogs with known allergies.
How much DHA do dogs need?
The National Research Council has established recommended allowances for EPA + DHA for all canine life stages, with a safe upper limit of 280 mg per 100 kcal for adult dogs. [16] Therapeutic doses for specific conditions like arthritis or skin disorders may be higher and should be discussed with your veterinarian. Petaluma's formulas are designed to provide appropriate DHA levels for maintenance and health promotion.
The Bottom Line
Marine microalgae provides an omega-3 source that matches fish oil's benefits while eliminating concerns about ocean contaminants and environmental impact. By going directly to the source that fish themselves depend on, algae-derived DHA delivers the same essential fatty acids in a purer, more sustainable form.
At Petaluma, our choice to use marine microalgae wasn't about compromise—it was about providing the highest quality omega-3 nutrition for dogs while making responsible environmental choices. The research confirms what we believed from the start: you don't need fish to get optimal omega-3s for your dog.
Experience the Petaluma Difference
All Petaluma formulas include marine microalgae-derived DHA for optimal omega-3 nutrition, balanced with quality plant oils for essential omega-6 fatty acids:
- Adult Formula - Complete omega-3 and omega-6 balance for daily health
- Senior Formula - Enhanced DHA to support aging dogs' brain and joint health
- Whole Food Mixer - Dehydrated complete nutrition with algae-derived omega-3s
References
- Lenox, C.E., & Bauer, J.E. "Potential adverse effects of omega-3 fatty acids in dogs and cats." Journal of Veterinary Internal Medicine, 27(2):217-226, 2013. doi:10.1111/jvim.12033
- Bauer, J.E., et al. "Enhanced omega-3 index after long- versus short-chain omega-3 fatty acid supplementation in dogs." Veterinary Medicine and Science, 7(2):370-377, 2021. doi:10.1002/vms3.373
- Pinto, C., et al. "Therapeutic effect of EPA/DHA supplementation in neoplastic and non-neoplastic companion animal diseases: A systematic review." In Vivo, 35(3):1419-1436, 2021. doi:10.21873/invivo.12387
- National Research Council. Nutrient Requirements of Dogs and Cats. Washington, DC: National Academies Press, 2006. Available at: https://nap.nationalacademies.org/catalog/10668/nutrient-requirements-of-dogs-and-cats
- Dahms, I., et al. "Safety of a novel feed ingredient, algal oil containing EPA and DHA, in a gestation-lactation-growth feeding study in Beagle dogs." PLOS ONE, 14(6):e0217794, 2019. doi:10.1371/journal.pone.0217794
- Zhang, Z.X., et al. "Evaluation of the efficacy and safety of omega-3 fatty acid nutritional supplements from Schizochytrium sp. in dog food." Animal Nutrition, 2025. doi:10.1016/j.aninu.2025.01.008
- Dahms, I., et al. "Safety of a novel feed ingredient, algal oil containing EPA and DHA, in a gestation-lactation-growth feeding study in Beagle dogs." PLOS ONE, 14(6):e0217794, 2019. doi:10.1371/journal.pone.0217794
- Fascetti, A.J., et al. "Analysis of selected nutrients and contaminants in fish oil supplements for dogs." Journal of the American Veterinary Medical Association, 2025. doi:10.2460/javma.24.11.0721
- Lenox, C.E., & Bauer, J.E. (2013). Op. cit. [Discussion of bioaccumulation and toxin exposure.]
- Bauer, J.E. "Role of dietary fatty acids in dogs and cats." Today's Veterinary Practice, 2022.
- Molfino, A., et al. "Omega-3 polyunsaturated fatty acids in critical illness: anti-inflammatory, proresolving, or both?" Oxidative Medicine and Cellular Longevity, 2017:5987082, 2017.
- Association of American Feed Control Officials (AAFCO). Official Publication. Champaign, IL: AAFCO Inc., 2024. Available at: https://www.aafco.org/resources/publications/
- Rees, C.A., et al. "The balance of n-6 and n-3 fatty acids in canine, feline, and equine nutrition: exploring sources and the significance of alpha-linolenic acid." Frontiers in Veterinary Science, 11:1423456, 2024. doi:10.3389/fvets.2024.1423456
- Bauer, J.E., et al. "Enhanced omega-3 index after long- versus short-chain omega-3 fatty acid supplementation in dogs." Veterinary Medicine and Science, 7(2):370-377, 2021. doi:10.1002/vms3.373
- Pinto, C., et al. "Therapeutic effect of EPA/DHA supplementation in neoplastic and non-neoplastic companion animal diseases: A systematic review." In Vivo, 35(3):1419-1436, 2021. doi:10.21873/invivo.12387
- National Research Council. Nutrient Requirements of Dogs and Cats. Washington, DC: National Academies Press, 2006. Available at: https://nap.nationalacademies.org/catalog/10668/nutrient-requirements-of-dogs-and-cats
