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Omega 3 in Fish Oils, Krill Oils & Other Oils

Fish & Krill Oil and Other Oils,
Human grade fish oil or krill oil are some of the few supplements recommended in the Prey Model Raw plan when it comes to dogs or cats with no specific health problems. These oils may be helpful though for treating conditions with an excessive inflammatory response like allergies and skin problems associated with them. However, a necessary level of inflammatory response must be maintained to protect the body and excessive amounts of EPA and DHA can interfere with that process.

Fish Oil:
In general fish body oil is mainly needed when the meat you feed is from animals that are grain fed and grain finished as that means you need to balance with more Omega 3 versus 6. Dogs and cats that are mainly eating wild caught meat as well as some fish/seafood wouldn’t really need it. If you feed truly grass-fed/pastured and finished, or wild caught part of the time, then you could choose to only dose when you are feeding commercially raised meats. Cattle fed primarily grass, significantly increase the omega-3 content of the meat and also produce a more favorable omega-6 to omega-3 ratio than grain-fed beef. Grass fed beef for example is also higher in precursors for Vitamin A and E and some cancer fighting antioxidants. Numerous studies have shown that cattle finished on pasture produce higher levels of α-tocopherol (Vit E) in the final meat product than cattle fed high concentrate diets.

The recommended ratio for Omegas 6/3 is thought to be around 4:1. Dogs cannot make their own Omega 3 fatty acids. This is why dogs have a dietary need for Omega 3 fatty acids like eicosapentaenoic acid (C20:5n-3,EPA) and docosahexaenoic acid (C22:6n-3,DHA).

Fish oil doesn’t need converting in the body from ALA (C18:3n-3, αLA, α-linolenic Acid) to EPA/DHA like plaint oils do. Dogs’ conversion rate is virtually none as they lack the metabolic pathways for such conversion.. (Humans’ conversion rate is not very high either, in general less then 5%.)

The fish body oil you give is best human grade because in general, pet products are not held to the same stringent production and disclosure standards as human grade products. It should have no additives, plants, flavorings or soy in it. Therefore should be just the oil and the gel cap. So no added vitamin E (which is usually soy), no tocopherols or mixed tocopherols (which are almost always soy). Tocopherols are fat soluble antioxidants (Vit E) which used to be mainly from wheat germ oil but now mostly soy. Also I would check that they purify their products to remove contaminants like mercury for example and that they have taken steps to prevent the oil going rancid.

You measure the dose by the size of the dog/cat. A maintenance dose (to bring Omega 3:Omega 6 ratios into balance) is around 100mg combined EPA/DHA per 5kg (10lb) of dog. For cats, halve that amount to 50mg. So a 50kg (100lb) dog would get 1000mg EPA/DHA total, daily. A typical gel cap will contain 300mg combined EPA/DHA. Check the back of the bottle, for the combined EPA/DHA and go by the gel cap, not the serving. So please note: the total amount of oil is not what we go by, but the amount of combined EPA/DHA in the oil. Be wary of supplements that list only the specific amounts of “Omega-3s” instead of “EPA+DHA”.

One teaspoon (5 ml) of oil contains about 42 kcal. So weight gain could occur when large dosages of omega-3 fatty acids are given.

The therapeutic dose for fish body oil is 300mg/per 5kg (10lb) of dog.

Some concern with fish oils is the oil being rancid. There has been a few articles in the news about that lately. Oils from spray bottles may go rancid quite quickly so look for caps, or you can freeze the oil to make it last longer... Rancid oil smells off, throw out if that is the case.

As for Vitamin E, mainly if you feed a therapeutic dose of fish body oil for a longer period of time, you might need to supplement with Vit E, but best not derived from soy but other oils.

Krill Oil
Krill oil is also a good alternative for dogs and cats ( but it gets quite expensive to feed in bigger doses). For Krill Oil, you also go by the combined EPA/DHA on the bottle. However, since Krill Oil is a Phospholipid and not a Triglycerid (Triglycerids are soluble in fat only) and therefore more bio-available than fish oil, it’s claimed that you need less of the EPA/DHA combination.

Krill oil is soluble in water (and fat) and doesn’t require bile to break it down, and because the oil mixes easily with stomach contents, it reduces any reflux or nausea that can be experienced with fish oils and anyone with digestive issues or liver or gallbladder problems may utilize it better.

It is said that fatty acids from krill oil are absorbed by the brain, heart and liver more efficiently than fatty acids from triglycerides (fish oil). This explains why you may require less krill oil than fish oil to achieve the same result even though the EPA/DHA amount may be significantly less than fish oil. A guess is that you can give 1/3rd or so of the dose you would give for fish oil. For 1/3rd it would be around 33mg/5 kg (11lbs) dog. (66mg for 10 kg (22lbs) dog and 198 mg for a 30 kg (66lbs) dog. We are talking about combined EPA/DHA of course...

Since krill oil contains Astaxanthin which is a natural antioxidant, you don’t need to worry about vitamin E while giving it. The real benefit of the Astaxanthin in krill oil is to provide antioxidant protection to the oil itself, keeping it fresh much longer than vitamin E could, for example.

Squid Oil
Squid oil has a good balance of EPA and DHA with low toxin levels and a the population of squid is rising steadily.

Squid live only about one to two years and their short lifespan makes them very adaptable to changing ocean conditions.

Squid is a rich source of EPA and DHA, and, because it lacks bones and is low on the food chain, tests have shown squid to be free of any detectable levels of toxins. So Calamari oil (squid oil) is said to be a good and pure source for Omega 3 and also sustainable.

Other Oils
Don’t feel tempted to give Cod Liver oil please, as it's high in Vitamin A and D and those are only fat soluble so will be a risk of Vit A toxicity as it's not excreted in the urine. Giving a high enough dosages of cod liver oil to supplement EPA & DHA on a regular basis can be dangerous for that reason. The safe upper limit for vitamins D and A for a 10 kg dog are 14.6lg cholecal-ciferol (584 international units) and 11,804 retinol equivalents of vitamin A.

Coconut oil is not a good alternative to fish body oil in spite of it being touted the “miracle cure” for basically everything. Here are the reasons why:

#1. It’s a plant oil and not species appropriate for dogs or cats. The fatty acids in plant based oils are in the form of alpha-linolenic acid, which needs to be converted to DHA and EPA to be of nutritional benefit. Dogs don't have the necessary enzymes to do that. (The same goes for flax oil and other plant oils)

#2. It’s very high in saturated fat and likely to put unwanted weight on your pet: 1 tbsp.(13.6g) coconut oil = 12g saturated fat.

#3. It has no Omega 3 but only Omega 6 ( linoleic acid), which is not beneficial since Omega 6 is abundant in most foods, and when too much Omega 6 is ingested it can create inflammation, pain, and increase illnesses. We always endeavor to balance this with giving Omega 3 like in fish body oil or by being mindful, if possible, of reducing the amount of meats that are high in Omega 6.

Coconut oil will however have it’s uses for topical application due to it’s lauric acid which provides a good antimicrobial/preservation and you can use it as a moisturizer and carrier oil.

Flax oil is not appropriate either as it is of course also a plant oil and not readily bio-available for cats/dogs.

The most common signs of fatty acid deficiency are:

• Dry skin and dandruff.
• Coat issues, lots of shedding and thin or greasy hair.
• Allergy symptoms, itching and eczema.
• Slow wound healing.
• Ear infections
• Inflammations

Consult with your vet before giving fish oils to a diabetic pet. Also it’s advised to discontinue any oils before surgery of any kind because of the blood thinning effect of these oils. Fish oil can prolong the time it takes blood to clot, so if your pet is going to have surgery, it’s best to stop the oil for at least five days before and five days after the operation. (Check with your vet).

The National Research Council has established a safe upper limit of EPA and DHA for dogs. It has yet to establish one for cats. Translating the data suggests that a dose between 20-55mg combined EPA and DHA per pound of body weight is safe for dogs.

Sources and links for your own research (but best to be critical of the ones promoting their own brands)
A review of fatty acid profiles and antioxidant content in grass-fed and grain- fed beef

Potential Adverse Effects of Omega-3 Fatty Acids in Dogs and Cats - Lenox - 2013 - Journal of Veterinary…

Related Articles
Fish Oil and Puppies
Using Omega 3 Fatty Acids Effectively and Safely

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