Essential Health For Dogs From Fish Oils...What you must know for your Dog's Sake

Jul 7, 2016

The Wonderful Goodness of Omega-3 Fish Oils For Dogs

Extensive research and veterinary patient studies continue to show evidence that the high intake of marine sourced omega-3 essential fatty acids EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid) can help improve your dog’s overall health.

Fish oil provides EPA and DHA Omega-3s, the long-chain most biologically active forms, and the many known benefits provided by these essential fatty acids to the overall health and wellbeing of dogs in all life stages such as:

  • Supple healthy hydrated moist skin and much less itchiness and hot spots
  • Shiny glistening soft coat and no more dull and dry rough looking coat
  • Less shedding
  • Healthy immune system function support
  • Protection against auto immune diseases
  • Anti-Inflammatory activity
  • Decreased inflammation throughout the body and organs
  • Reduced joint inflammation, pain and discomfort
  • Increased fertility of male dogs
  • Increased energy and stamina
  • Brian nerve and eye development of puppies = smarter more easily trained puppies.
  • Reduces and slows the cognitive decline of senior dogs
  • Reduced risk of brain, heart and kidney health issues
  • Reduction in cancer risk


Dogs actually require two very different kinds of essential fatty acids for normal development and good health maintenance, Omega-3 and Omega-6. The omega-6 fatty acids are overly excessive in a dog’s diet as they are very commonly found in almost everything that they eat. The fish oil marine type long-chain omega-3s EPA and DHA however are not commonly found in appreciable amounts in today’s dog foods and diets.


The ideal total omega 3 to omega-6 dietary intake ratio is something like 1:1 or 1:3 which is similar to the diet of paleo hunter-gatherers, the time over 10,000 years ago when mankind and dogs formed a bond of mutual benefit, the ratio of omega-6 to omega-3 has been estimated at 2:1 or 3:1.This is in contrast to the very inflammatory modern dog diet (much like the standard human Western diet).which has been estimated at 1part omega-3 to 10 parts of omega-6, or even 1 to 25. Interesting in the early 1900s the omega 3:omega-6 intake ratio in the United States human diet was estimated to be 1:5. Today, largely due to the 1,000 times increase of soybean and vegetable oils use in our diets over the last several decades, the dietary omega 3:omega-6 intake ratio is now 1:10 to 1:25.


What are omega-3 and omega-6 fatty acids and what do they do?

Omega-3 and omega-6 fatty acids are two different forms of essential fatty acids that have very important roles in cell membrane structure, fluidity and hormonal cell signaling. The designation 3 or 6 is related to their chemical structure. The most common and abundant dietary essential fatty acids in the dog’s diet are the short-chain omega-3 alpha linolenic acid (ALA) found in flax seeds and chia seeds. The short-chain omega-6 linoleic acid (LA) is found in high amounts in soy, canola and sunflower vegetable oils.


The long-chain omega-3 essential fatty acids EPA and DHA, commonly referred to as marine fatty acids, are most biologically active and provide many health benefits are easily obtained from fatty cold water fish such as salmon, herring, anchovies, menhaden and sardines. DHA omega-3 is now also available from specially selected marine sourced algae. The long-chain omega-6 fatty acid AA (arachidonic acid) is found in eggs, poultry, and meat.


Unless a dog directly eats the long-chain omega-3s EPA and DHA, and long-chain omega-6 AA the dog’s body will make them utilizing specific enzymes. The enzymes, desaturases and elongases, will convert the short-chain omega-3 ALA found in plant seeds and oils like flax seed and chia seed to the more biologically active and health protecting long-chain omega-3s EPA and DHA. In the same way these enzymes, desaturases and elongases, will make long chain omega-6 AA from the short-chain omega-6 LA. The same enzymes are involved in making long-chain omega-3s and long-chain omega-6 from commonly available short-chain versions.

Given that the modern dog diet has 15 – 25 times more short-chain omega-6 LA (vegetable oil sources as they are a low cost energy (calories) source) in it than it should have the enzymes are force driven to make excessive amounts of the pro-inflammatory pain causing, immune suppressing long-chain omega-6 AA. Excessive amounts of omega-6 LA suppresses the amounts of anti-inflammatory and health beneficial long-chain omega-3s EPA and DHA produced by the body.


How to make omega-3 and omega-6 balance?

Although the omega-3 and omega-6 imbalance is due to excessive omega-6 consumption brought about by a high level of vegetable oil consumption the most practical, easy remedy is simply to increase the amount of fish oil sourced marine long-chain omega-3s EPA and DHA in the diet. This is far easier than trying to greatly reduce the amount of omega-6 in the dog’s food and diet.

The plant sourced (flax or chia seed) short-chain omega-3 ALA can be very helpful to help balance the omega-3 to omega-6 ratios however it does not deliver the same biological effects of long-chain omega-3s EPA and DHA as rapidly and as assuredly.


What to look for when buying pet supplement fish oils?

1          Low contamination

A major concern that is not very widely recognized is that many low cost feed or pet grade fish oils on the market are contaminated with relatively large amounts of heavy metals and toxic chemicals. Toxins like mercury are typically screened for at least in higher quality pet brands however there are other contaminants that are unlikely to be tested for or removed.

Some of the most common contaminants found in fish and thus fish oils include:

  • PCBs
  • Dioxin
  • PDEs
  • PCP's
  • Toxic metals such as mercury, cadmium, lead, chromium and arsenic


Smaller fish lower on the food chain, such as herring, sardines, menhaden and anchovies are better than larger predator fish since they have not become large and old and as such have not had time to bioaccumulate heavy metals and other toxins in their tissues and body fat.

A salmon is going to have less toxins and heavy metals in it than a huge grandfather tuna. A large tuna has a lot more mercury and other heavy metals in them because they're older fish and they accumulate these things in their body.


Reputable pet health supplement companies will use only cleaned HUMAN GRADE FISH OILS which have been thoroughly tested for ALL CONTAMINANTS and refined to remove the toxins and heavy metals to extremely low levels. Only about 2 -3% of the fish oil produced is destined for human grade supplements, the vast majority is used for fish food and livestock uses.


2          Omega-3 Fats are Incredibly Fragile

Omega-3 fats whether animal sourced or plant source are fragile and are VERY easily damaged by high heat, oxygen and light.

Because long-chain omega-3s EPA and DHA are extremely fragile and easily become rancid and oxidized they are typically lacking in commercial dog foods that we tend to feed our dogs.

While pet food labels may state that Omega-3 essential fatty acids have been added, the reality is that the food will be very low in Omega-3 and often devoid of the marine based DHA and EPA Omega-3s due to the technical difficulties of pet food manufacturing and the unavoidable exposure to high heat, air and light.


Rancid fish oil smells bad and also tastes awful. It is important to understand that rancid fish oil is not at all beneficial and can be harmful.

Consuming rancid fish oil causes a reaction in the body known as oxidative stress in the cell membrane. Fats are an integral part of cell membranes and essential to inter/intracellular signaling throughout the body. These fatty acid chains in the cell membrane are easily oxidized by “free radical” damage. This free radical damage takes place when a high energy particle, known as an electron, “bounces around” looking for a place to land and give up its energy. Free radical damage cells is problematic because the energy from that loose free radical electron can be passed from one fat chain to another in a true “chain reaction” as that electron’s excess energy bounces from one fat chain to another doing damage all the way.

When a dog consumes rancid fish oils, their body must use its stores of antioxidants such as vitamin E to neutralize the rancid oils, leaving fewer of these critically important anti-oxidant resources available to their body for free radical protection, cellular repair and disease prevention.

Feeding a very high quality FRESH FISH OIL Omega-3 supplement is therefore highly advised in order to make certain that your dog receives the many known health benefits of marine based long-chain omega-3s EPA and DHA.


Evaluate your current fish oil product packaging. The best way to tell whether or not your omega-3 fish oil supplement is fresh is the smell test. If you have a jug of fish oil or a pump bottle with a type of shampoo pump – both of which permits air into the container very likely the fish oil is rancid after about a week after opening the package. If the oil looks dark and your nose gets a whiff of something that reminds you of dead rotten fish then your fish oil is rancid.

Bigger is NOT better. If buying a liquid form of fish oil only purchase small containers. The more times that a container is opened and closed the more air and oxygen will get mixed in and over time the fish oil becomes rancid over time. KEEP ANY CONTAINER THAT AIR ENTERS INTO IN THE REFRIGERATOR AFTER OPENING. The cold slows down oxidation and rancidity.

Shampoo pumps are NOT designed for fish oil: Shampoo type bottle pumps push air and thus oxygen into the fish oil and thus making it oxidized and rancid. There are very special medical AIRLESS PUMPS that WellyTails fish oils are packaged in in order to keep air and oxygen OUT of the bottle container and thus the oil. These special WellyTails “airless dosing pumps” make it easy to always be providing a healthy fresh fish oil.

General Fish Oil Information: 

Where do we get Omega-3 from?

Long-chain omega-3s EPA and DHA are found typically in fatty fish such as mackerel, salmon, herring, sardines, sablefish (black cod), anchovies, albacore tuna, menhaden. Also special marine algae.

Short-chain omega-3 ALA is found abundantly in flax seed, chia seed, and hemp seeds.

My dog’s food already states it has omega-3 for skin and coat so why am I not seeing improvement?
Most likely the source of the omega-3 is plant based short-chain omega-3 ALA, most likely ground flax seed. Or it may have a very low amount of long-chain omaga-3s EPA & DHA as these are costly and very difficult to keep from becoming rancid and providing nasty off flavors in the dog food.

Best to use a high quality FRESH FISH OIL as a dietary supplement. Dose is calculated at total long-chain omega-3s EPA and DHA total of 10 to 20 mg active per pound of body weight. 50 pound dog needs 500 to 1000 mg combined of EPA & DHA. Each dog will have a different need depending on how much more it needs above what is supplied in the diet.


How do I figure out how much long-chain omega-3 EPA and DHA am I giving to my dog?

Many pet store fish oil labels seem to purposely confuse the issue to mask inferior or diluted products. There actually is a so called “Omega-3” pet product that is selling extremely well that is basically just soybean vegetable oil with a lovely picture of a dog on the label! It sells for $24.95 a quart meanwhile soybean oil at the local grocery store is only $5.95 for a quart. BUYER GET EDUCATED as your friendly pet store staff may themselves just not fully understand omega-3s properly.

A pet omega-3 fish oil product label may say that the dosage is 1000mg of fish oil per 20 pounds of dog weight. Thus a 60 pound dog would receive 3000mg of fish oil. Sounds like a good dose?

Scenario Standard Human Grade Fish Oil

Typically a standard high quality human grade fish oil sourced from sardines or anchovies or mackerel will have been cleaned of all contaminants and standardized for the amount of long-chain omega-3s EPA and DHA. In 1000mg of this fish oil there are 180mg of EPA and 120mg of DHA = 300mg of long-chain omega-3s. Most often this fish oil active ingredients are expressed as a 180:120 fish oil. Thus 180mg EPA + 120mg DHA  = 300mg active ingredients per 1000mg of fish oil which works out to 30% active ingredients [{300mg EPA+DHA  divided by 1000mg fish oil} times 100] in 1000mg of fish oil.

Now let’s calculate how much EPA +DHA that 60 pound dog is getting from 3000mg of fish oil.

3000mg standard 180:120 fish oil x 0.30 =  900mg of  EPA + DHA active ingredient dosed

Scenario Wild Alaskan Salmon Oil

A pet omega-3 Wild Alaskan Salmon fish oil product label may say that there are TOTAL of 290mg of omega-3s per 1000 mg of the oil.  The label directs that dosage is 1000 mg of fish oil per 20 pounds of dog weight. Thus a 60 pound dog would receive 3000mg of Wild Alaskan fish oil and thus 870mg of TOTAL OMEGA-3s. Sounds like a good dose HOWEVER IS IT REALLY?

Typically a standard WILD ALASKAN SALMON OIL of very high quality human grade will have been cleaned of all contaminants and standardized for the amount of long-chain omega-3s EPA and DHA. Typically Wild Alaskan Salmon will have slightly less EPA than DHA depending on wild salmon species harvested. On average with some seasonal variability typically in 1000mg of wild Alaskan salmon oil there are 90mg of EPA and 110mg of DHA = 200mg of long-chain omega-3s or put another ways it is an 90:110 fish oil Thus 90mg EPA+ 110mg DHA = 200mg active ingredients per 1000mg of Wild Alaskan Salmon oil which works out to 20%active ingredients (200mg of EPA+DHA divided by 1000mg fish oil).

Now let’s calculate how much EPA +DHA that 60 pound dog is getting from 3000mg of fish oil.

3000mg of standard 90:110 Wild Alaskan Salmon oil x 0.20 = 600mg of EPA + DHA active ingredient dosed


Wild Alaskan Salmon oil is delivering 30% LESS EPA + DHA omega-3 active ingredients compared to regular standard human grade 180:120 fish oils.

Pet parents and pet store staff are very often confused by the Wild Alaskan Salmon oil label that highlights TOTAL omega-3s (there are several different kinds of omega3s in fish oils) versus clearly listing the amounts of active ingredients.

Human grade Wild Alaskan Salmon oil is typically more expensive than standard human grade fish oil and given that it delivers 30% less active EPA +DHA omega-3s it works out to be a very expensive choice of fish oil to use.

QUESTION: How do I figure out how much EPA + DHA to dose my dog?
Reply: For skin and coat and joint anti-inflammatory health issues you would want to feed 20mg of combined EPA +DHA omega-3s per pound of body weight daily. For example, if your dog weighs 50 pounds you multiply that by 20mg/per pound body weight (50 lbs. x 20mg = 1000mg)  weight to get a target dose of 1000mg of EPA + DHA omega-3 active ingredients required.

The amount of standard human grade 180 EPA:120 DHA fish oil needed is calculated by dividing the target amount of EPA + DHA required by the percentage of active ingredients in the fish oil. 1000mg of EPA + DHA needed divided by 0.30 (30% active found in fish oil) tells you that you should feed about 3330mg (3.3 grams) of standard human grade fish oil daily 

The amount of standard human grade Wild Alaskan Salmon oil 90 EPA:110 DHA   needed is calculated by dividing the target amount of EPA + DHA required by the percentage of active ingredients in the fish oil. 1000mg of EPA + DHA needed divided by 0.20 (20% active found in fish oil) tells you that you should feed about 5000mg (5 grams) of standard human grade Wild Alaskan Salmon oil daily 

NOTE: For typical health maintenance and preventative measures HALF of the above of the amount is sufficient. ALWAYS USE FRESH FISH OILS - Freshness does matter.


QUESTION: Does the ratio of EPA to DHA matter?
Reply: Research does clearly indicate that EPA omega-3 provides a stronger and better anti-inflammatory effect than DHA omega-3.  For most of the health issues that our furry friends need help with, skin and coats, allergies and joint pain issues) you do want to use a fish oil that is higher in EPA than DHA. . A standard human grade 180 EPA:120 DHA fish oil is technically a better choice than Wild Alaskan Salmon oil in this instance.


QUESTION: How long does it take before we can see results?
Reply: As with most natural dietary products it will be 3 -4 weeks before any significant change can be observed or measured. It takes 21 days to see the higher elevated levels in blood.  If after 3 or 4 weeks of daily feeding the required amount for dog’s body weight daily and a notable improvement is not seen it is best to consult with your veterinarian regarding the condition. They may advise to double the dosage as some animals just need more nutrients.


QUESTION: Is there any danger of my overdosing my dog with fish oil?

Reply: Clean human grade fish oils are very safe to use at high dosages as there are no toxic short or long term effects. Human grade fish oils are very safe. The only issue would be that with extremely high fish oil dosages the dog’s ability to digest the TOTAL amount of fat in the diet (fat from dog food, treats and fish oil) is exceeded and the dog gets soft stools or diarrhea. Lowering the amount of fish oil fed would solve the problem.


QUESTION: Should I feed a3-6-9 Omega oils blend?

Reply: There are many good marketers that have made “3-6-9” omega oil blends popular!  Typically they contain only the short-chain ALA omega-3 fatty acids (a-linolenic acid (ALA) from flax oil or other plant sources) along with short-chain omega-6 fatty acid (as linoleic acid from common vegetable oils or gamma-linolenic acid from sources such as primrose or borage oil) and omega-9 fatty acid (which is a common constituent of olive oil, canola oil, soybean oil and numerous other vegetable oils). The dog body has a capacity for naturally and readily biosynthesizing the omega-9 fatty acid (oleic acid) by the existing metabolic pathways in dogs. Omega-9 is not regarded as an essential fatty acid in the diet because of its ease of formation in the body.

Given that dogs in the USA and Canada and those in most other countries have very high intakes of short –chain omega-6 LA fatty acid spending money to feed them more


QUESTION: What is the difference between fish oil and flax seed oil?  

Reply: All fish oils contain long-chain omega-3 fatty acids including some EPA and DHA in varying amounts depending upon the specific fish type. Most fish oils contain very little to trace amounts of the plant-based short-chain omega-3 fatty acid known as alpha-linolenic acid (ALA). In contrast, flaxseed and flaxseed oil contains approximately 53-57% of the total fatty acids as ALA omega-3 while being devoid of the long-chain omega-3s EPA and DHA.

The long-chain DHA omega-3 fatty acid found in fish oils is very important for the provision of DHA for brain, eye and nerve development. DHA is the optimal functioning. Omega-3 and is physiologically essential nutrient for the brain. It is well established by researched that there is very little conversion of dietary/nutritional sources of short-chain omega-3 ALA into long-chain omega-3 DHA in the mammal body (including puppies).  Thus feeding pre-formed DHA omega-3 is of great importance for ensuring an adequate supply of this important nutrient.


QUESTION: I heard that the omega-3 from KRILL oil was like 20 times more bioavailable and effective than the omeg-3s from fish oil. Is that right?

Reply: Controlled studies have indicated that omega-3 fatty acids from standard fish oil have bioavailability in the range of 80-90%. If any alternate omega-3 source oil actually delivered even just double the bioavailability then that would mean that it was 160-180% bioavailable. This is impossible since the maximum digestibility for any dietary fatty acids is 100%. Krill oil is indicated to actually be digested and thus absorbed slightly quicker than some forms of fish oil.


QUESTION: Are there any plant or vegetarian sources of EPA or DHA omega-3?

Reply: Natural plant nuts, oil seeds and vegetable oils are totally devoid of the long-chain EPA or DHA omega-3, they do have varying amounts of the short-chain omega-3 fatty acid alpha-linolenic acid (ALA). Thus, the presence of ground flax seed or flax seed oil (naturally rich in ALA omega-3) in a food product would provide varying amounts of ALA but no EPA or DHA. Over the past several years, commercial sources of algae strains have been isolated and developed to produce an algal oil derived from these algae which does contain DHA omega-3. Today there are algae strains delivering both EPA and DHA omega-3. These algal oils do provide a vegetarian source of the highly bioactive omega-3s EPA and DHA.


QUESTION: Will cod liver oil provide EPA and DHA omega-3s?

Reply: Basic cod liver oil typically contains approximately only 9% omega-3 fatty acids EPA + DHA while a standard human grade fish oil will have 30% omega-3 fatty acids EPA + DHA and Wild Alaskan Salmon oil will have 20% omega-3 fatty acids EPA + DHA.

Fish oil and cod liver oil are very different oils although they do both naturally come from fish.

Fish oil is extracted from the body fat of fish like anchovies, tuna, sardines, herring, mackerel and salmon, typically oily ocean fish species. Fish oil is very rich in the omega-3 fatty acids EPA and DHA but has no vitamin A or D.

Cod liver oil comes from the liver of the cod fish. It has much less EPA and DHA omega-3s but is very rich in the fat soluble vitamins A and D. It was routinely spooned out to children in the 1960s as a source of vitamin D in northern Europe and Canada where sunlight is limited during their long dark winters.


QUESTION: Is there a difference in the amount of EPA + DHA omega-3 in Atlantic farmed salmon vs Wild Atlantic salmon?

Reply: Studies report that both farmed and wild Atlantic salmon have about the same amounts EPA + DHA in 100grams of salmon meat (One Canadian study showed that farmed had 855mg and Wild had 749mg per 100grams of salmon meat). NOTE: the amount of EPA + DHA omega-3 fatty acids in farmed Atlantic salmon fish will be directly reflected from the amount of EPA + DHA that has been added to the fish feed in the fish farming operations. Typically farmed fish have the same amounts as wild fish however this is not always true.


QUESTION: Are there any differences in the stability and efficacy of the natural Triglyceride (TG) form and the Ethyl Ester (EE) form of EPA and DHA fatty acids?

Reply: The natural form is the TG (triglyceride) form whereas the EE (ethyl ester) form is derived from further processing. The EE form is more readily concentrated to make up the fish oil to go into gelatin capsules that are the same 1000mg normal size however may deliver  2 to 3 times as much EPA +DHA in the 1000mg gelatin capsule than standard fish oil. Some humans hate to swallow pills so this way they just need to swallow 1 instead of 3 to get a high dosage.

Upon such concentration, the processor may choose to re-convert the EE form back to the TG form. Thus, both TG and EE forms of EPA/DHA concentrate exist in the gelatin capsule marketplace. The majority of studies, in humans, have shown very little difference if any in the bioavailability (if taken at or close to meal time) or efficacy of the EE as compared to the TG form assuming identical intakes of the omega-3 fatty acids. Some recent German studies have clearly shown that TG form is absorbed 15% better than the EE form.

When the EE form is consumed, the omega-3 fatty acid is released inside the gut along with the release of some small amounts of ethanol (alcohol). If 1000 mg of omega-3 fatty acid were consumed in the EE form, this would release/generate approximately 150 mg of ethanol which is approximately 1% the amount of ethanol in a 12 oz. bottle of beer.

Studies clearly show that the EE form is less shelf stable the TG form and the EE form will oxidize more rapidly.

Bottled fish oils which are opened and closed or those with shampoo bottle pumps are very prone to becoming rancid and oxidized compared to fish oils products that have had air (oxygen) excluded from them.

TG form of fish oils packaged in small dark bottles and kept in fridge or airless fish oil pumps and gelatin capsules are the best way to ensure that you have FRESH FISH OIL. 


QUESTION: Some websites warn that fish oil that has become rancid and oxidized due to exposure to air, high heat or light and should be avoided. Do you agree? 

Reply:  Rancid fish oil can be responsible for creating free radicals which are harmful to health as they may cause damage at a cellular level. Fish oil can be harmful if it is rancid and oxidized as it can release large amounts of free radicals in the body, which can cause cancer and other diseases. Omega-3 essential fatty acids are known as polyunsaturated fatty acids. EPA and DHA are both highly unsaturated fatty acids. The more unsaturated that a fat is, the more likely it is to go rancid quickly. In contrast a saturated fat like coconut oil can be exposed to air for a long time without turning rancid. The fragile unsaturated nature of the fish oil fatty acids makes them very susceptible to light, high heat, and air oxidative damage. When damaged, the fats in fish oil oxidize and become lipid peroxides, which cause free-radical damage, hence proponents of diseases, such as cancer and auto-immune issues. Consumed rancid oxidized fish oils pull down the vitamin E levels in the body and well as the overall antioxidant status levels thus allowing more free radical damage to occur.  The theory of premature aging is also associated with free-radical damage.

Preventing Fish Oil Rancidity and Oxidation

To prevent rancidity, choose products made only from quality human grade fish oils and minimize their exposure to air, high heat and light. Buy the freshest supplements (far away from the best before date) you can find. Choose pet supplements from reliable science based manufacturers and not marketing companies. Refrigerate your supplements as soon as possible. Only choose fish oils packaged in small dark bottles and keep them refrigerated after opening airless pumps or gelatin capsules.

DO NOT BUY fish oils packaged in a large jug unless you will repack it yourself into small 200ml dark bottles and keep them refrigerated, bottles with shampoo type pumps as these are pushing damaging air into the fragile delicate fish oil.

Most pet supplement manufacturers protect their fish oil supplements with natural forms of vitamin E known as tocopherols to help prevent or slow oxidation and rancidity from occurring; check labels for the mixed forms of tocopherols, gamma and delta tocopherols in addition to alpha tocopherols . The addition of rosemary oil extract as a natural antioxidant to protect the fish oil may also be used instead of vitamin E or in combination with vitamin E. 

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