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Discover how to choose the best supplements for your pet’s health, from essential vitamins to joint support and digestion aids. Learn age-specific and seasonal supplement tips for cats and dogs.
Updated on October 23rd, 2025
Feeding your pet a quality food shouldn't break the bank. Use these tips to find the right diet, and price point, for your pet's meals.
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Learn about the benefits of fish oil for dogs. Order online from Petco and save with Repeat Delivery or Curbside Pickup.
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Do you top your cat or dog's food? Find out how pet food toppers can help round out your pet's bowl.
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You are welcome, I'm glad to help you! Honestly, I'd go with the Nordic naturals simply because they are gel pills. That's because they will be easy to hide in some peanut butter or meat to give your dog. The liquid fish oil should be added to your dog's food, and if he doesn't like the taste, he won't eat the food. But if you think he will eat the food with the liquid fish oil on it, you can use the RX vitamins. I think both look good personally.
No studies have been done comparing the different potential sources to the best of my knowledge,. Rather the research has been approached as looking at fish oil as a whole. I suspect the salmon or cod are the best sources since they are more similar to mammals which generally means they are broken down easier. There are a few things to know and consider before starting this type of supplement. Heavy metals and other toxins, as well as contaminates, are not uncommon so I recommend to speak with your veterinarian about a recommendation that is not only purified but also verified to be free of contaminants. Here are some helpful links: https://vcahospitals.com/know-your-pet/fish-oil https://www.petcoach.co/article/omega-fatty-acids-sources-effects-therapeutic-uses-in-cats/ Dosage varies based upon the product and instructions will be on the package (it will be based on weight). Your veterinarian can help you to determine an appropriate dose. Best of luck.
I love Nordic Naturals and I always recommend using a veterinary product when available. They do tests to make sure you are giving the right amount for your dogs size. So while you can give fish oil from Costco I would stick to a veterinary formulation. Thanks for using Boop by Petco to help you care for Chloe.
Cod liver oil contains a large proportion of vitamins and minerals which can be difficult to adjust in small dosages. A blended omega fatty acid supplement formulated specifically for cats is preferred such as viacutan, omega aid or vitacat. Other options are specialist skin diets such as hills or royal canin which are additionally supplemented with natural antiinflammatory and coat conditioning ingredients
If she is on a high quality, balanced diet I would be cautious about over supplementing her as this can lead to dietary excesses (especially with cod liver oil type supplements as they can be high in certain vitamins also). Plant based supplements such as viacutan may also be an option but 3-5 days a week is likely sufficient