Nordic Naturals Omega-3 Pet vs Salmon Oil: Which Suits a Large Senior Dog?

Here is the short answer, since that is what you came for: I use Nordic Naturals Omega-3 Pet for Biscuit, I have since January 2025, and if I were starting over tomorrow with the same 72 pound dog and the same X-rays, I would buy it again. Salmon oil is not a bad choice. It is a reasonable source of omega-3s and for plenty of dogs it is the right first step. I picked the bottle that tells me what is in it, because I am the one measuring it over the kibble at seven in the morning, and I expect to be doing that for the rest of his life.

Two things to get straight. I have never given Biscuit salmon oil, not once, so when I talk about it I am talking about labels, about what Dr. Amundsen has said to me over the years, and about what you can find out by turning a bottle around in an aisle. And second, everything I know about my own dog comes from a paper log on the kitchen counter, one line a day: how he got up, how the stairs went, how far we walked. I used to hand logs like that to seventh grade clarinet players. It turns out a dog is not so different. Without the log I would be guessing, and I would rather tell you nothing than guess.

	Nordic Naturals Omega-3 Pet	A typical salmon oil
What the label tells you	1380 mg fish oil with EPA and DHA named, triglyceride form, non-GMO, no artificial colors, flavors or preservatives	Often the words salmon oil and very little else
How it goes on the bowl	Unflavored liquid, measured over the kibble	Liquid, measured over the kibble
Smell in the kitchen	Fish. Glen notices every morning	Fish as well
What it is sold for	Coat, eyes and heart, all named on the bottle	Usually sold as a coat and skin oil
Allergen stated	Fish, named outright	Varies by brand
Cost	Priced like a specialty fish oil	The cheaper bottle on the shelf
Where you find it	Online, and some independent pet shops	Grocery store, farm store, almost anywhere

Where Nordic Naturals Wins

Turn the bottle around and the difference shows up in about thirty seconds. The label gives the fish oil at 1380 mg with EPA and DHA named, it says the oil is in the triglyceride molecular form, the form naturally found in fish, and it commits to non-GMO ingredients with no gluten, no dairy, no artificial colors, flavors or preservatives. It names fish as an allergen outright. Most salmon oil bottles I have picked up in the farm store say salmon oil and very little else. When you are giving something daily to a ten year old dog with sore hips, the difference between a label that answers questions and one that does not is most of the decision.

I want to be honest about what I actually saw, because this is where a lot of reviews get slippery. I did not see a joint change from the fish oil that I could point to in the log. Not at six weeks, not at eight. The hips did what they did on Cosequin, which came first in October 2024, and that is a story for another page. What did change was his coat. By about eight weeks on the Nordic Naturals bottle it was softer and less flaky than it had been, and that has held. He is a yellow dog who sheds anyway, so I am not claiming a transformation. I am telling you what the log and my hands on his back can support.

The other thing this bottle wins on is that I never have to re-decide about it. It has lived in the refrigerator door since January 2025, twenty two months now, unflavored, and Biscuit has never once turned his nose up at it or had a bad reaction. One caution if you are comparing this to your own dog: the listing files it under medium breed size, and Biscuit is seventy two pounds, which is not medium. The bottle gives amounts by weight and Dr. Amundsen set his. I am not going to hand you a number, because your dog is not my dog. Follow the label and ask your vet.

One more thing, and it is the unglamorous part. Fish oil is one of five things that go on Biscuit's kibble at seven in the morning, in the same order every day, and nothing goes on at dinner. The Nordic Naturals bottle is the easiest of the five in my hand, because it is liquid and unflavored and it disappears into the kibble. He does not even know it is there. That sounds like a small thing until you have spent a week coaxing a tablet into a dog who has decided he does not want it, which is exactly what happened with the first Cosequin tablet in October 2024. He spat it out, and everything has gone on the kibble ever since.

In twenty two months I never saw a joint change from the fish oil that I could point to. What I could point to was his coat, softer and less flaky by about eight weeks, and a bottle I never once had to guess about.

Where Salmon Oil Wins

Cost, and I am not going to be precious about it. Glen and I are both retired. When a bottle you give every single morning is cheaper, that is not a compromise, that is how you keep the habit going for years instead of months. If the choice is between a specialty fish oil you stop buying in March and a salmon oil you can keep buying, buy the salmon oil. A supplement only does anything while it is still in the bowl.

Availability is the second thing, and it matters more than people admit. Salmon oil is in the grocery store, the farm store, the place you already stop on Saturday. The Nordic Naturals bottle I order, and when I have forgotten to order it I have driven to two shops before finding it. The Sunday you run out is the Sunday the habit breaks.

And if I am being fair, salmon oil is the right answer for a lot of dogs. A younger dog with no joint diagnosis, a dog whose only issue is a dull coat, an owner who wants to try omega-3s before committing to a bottle they have to order. Where I part company is the label. If a salmon oil does not tell you how much EPA and DHA is in it, or where the fish came from, you are guessing, and a guess given daily for two years is not a small thing. Read the back of both bottles before you decide. Then ask your vet, the way I ask Dr. Amundsen, because she is the one who has to look at the X-rays.

If you do buy salmon oil, here is what I would want on the back of the bottle before I carried it to the counter: the amount of EPA and DHA per measure, the species of fish, and a note about how it is preserved. Fish oil goes off faster than people think once the seal is broken, and a bottle that has sat on a warm shelf for a year is not the bargain it looked like. Ask the person at the counter how fast they turn that shelf over. If they do not know, order something else.

I should also say that I know people who use salmon oil and are perfectly happy with it, including a woman at the feed store whose old dog does well on a brand she has bought for years. I am not going to tell you she is wrong. What I would tell you is to ask her which bottle, and why that one, because if she can answer, she has done the work. That is the whole test, whichever bottle you carry out of the store.

Who Should Buy Which

Choose the Nordic Naturals bottle if your dog is a large senior with a real diagnosis behind the stiffness, the way Biscuit has arthritis in both hips on X-rays from September 2024. Choose it if he is already on three or four things and you want the one you add next to be the one you can read plainly. Choose it if you are the sort of person who keeps a log and will notice at eight weeks whether the coat changed, because that is the change I can honestly say you might see.

Choose salmon oil if your dog is younger and sound, if the problem is a coat and not a joint, or if money is tight enough that a specialty bottle would be a short term purchase. Choose it if you want to find out whether your dog will even take oil on his kibble before you spend on something you have to order. What I would not do is buy the cheapest salmon oil on the shelf without reading it. The whole advantage of the Nordic Naturals bottle is that it answers questions. A salmon oil that answers them too is a fine choice.

Understand what neither one does. Fish oil supports joints and skin and heart, it does not treat arthritis, and nothing I have given Biscuit has made him run or jump again. He is steady coming down the thirteen indoor stairs and still slow going up. Cold wet mornings are still his worst. The first change I ever saw came about six weeks after Cosequin in November 2024, and the fish oil joined three months later. Because of that I cannot prove which one did what, and I have stopped pretending otherwise.

If I were starting from scratch today with a dog at ten, I would do what I did, just in a different order of knowing. I would get the X-rays and the vet's read on the hips first, start the glucosamine, and give that six or eight weeks on its own before adding anything. Then I would add a fish oil, because it is the one the vet asked for by name, and I would choose the bottle with the numbers on it. Everything else can follow, one at a time, months apart, so the log has a chance to say something.

And one last thing that is not about either bottle. If your dog has not had X-rays, that is where the money goes first, before any supplement on any shelf. I spent months assuming Biscuit was just getting older. Dr. Amundsen put a picture up on the screen in September 2024 and there it was, arthritis in both hips, and suddenly a bottle made sense to buy. You cannot choose a supplement for a problem you have not named.

If your dog is on any medication at all, the fish oil is a conversation with your vet before it is a purchase. Dr. Amundsen read every label before Biscuit started anything. That is the habit I would copy before I copied any of my choices, including the one I am recommending here.