Fish, itself, is not dangerous for your dog to consume. However, industrial pollution and toxins accumulate in fish, which makes them unsafe to eat. Large fish, such as tuna, can build up high levels of mercury over the course of their lifetime. Both fresh and canned tuna (or tuna in soft packets) rank among the top in high levels of toxins. Dogs fed tuna regularly are at risk for mercury poisoning.
Tuna should be considered a treat and therefore, fed in moderation, advises Lissa Cannady, RVT, Hospital Manager for VCA. It is okay to feed your dog small amounts of cooked or canned tuna or any other fish a few times a month. It’s not advisable to use tuna as a main source of protein in a meal.
What kind of tuna can I feed my dog?
Don’t be alarmed if your dog sneaks a bite of tuna. A small amount will not do any harm. The safest tuna for your dog is those with the least amount of mercury, such as skipjack or albacore tuna rather than any other types of tuna, like yellowfin tuna. If you feed your dog canned tuna (or tuna in soft packets) for a small treat, it should be canned in water, not oil, and with no added salt.
Feeding tuna to your dog or even yourself is a highly debated topic because of the mercury concerns. If you love the health benefits of tuna for your dog but are concerned about mercury levels, talk to your vet about what type and how much canned or cooked tuna to feed your dog considering his age and health history. Want more information on tuna and mercury levels? Consumer Report’s recently studied different types of popular canned food for mercury amounts. See the result here. And, check out the FDA’s guidelines here. Got a cat in the household and wondering about feeding tuna to your cat? The answer is pretty much the same as feeding tuna to your dog, check out our sister publication Catster’s article Tuna for Cats — Let’s Learn the Truth.
For a raw diet, opt for wild-caught tuna or consider alternatives, such as salmon or arctic char, which rank lower in pollutants. We recommend cooking raw fish before feeding it to your dog. Raw fish contains an enzyme called thiaminase, which can disrupt thiamine (vitamin B1) function. Consult your vet before making changes to your dog’s diet or if your dog consumes more tuna than advised.
Is tuna good for dogs and is it in commercial dog food?
Tuna is used in commercial dog foods, though not as much as whitefish or salmon, which are much lower in mercury. Except for the possible high mercury level, tuna is a good high source of protein, plus it’s low in saturated fats and sodium. It’s also a good source of antioxidants, and omega-3 fatty acids, as well as a variety of vitamins and minerals.
You can check the pet food company’s FAQ section or reach out on the contact page to ask about their commercial dog food that contains tuna. Some companies use lighter and younger fish that have not accumulated much mercury or test their tuna regularly for mercury levels.
What does mercury poisoning from fish look like?
If you are going to regularly feed your dog tuna, familiarize yourself with the symptoms of mercury poisoning. These can include:
- muscle twitches and tremors
- decreased brain function
- kidney and respiratory failure