Omega 3 is vital for good dog skin health and can solve many itch dog allergies.
Flax seed doesn’t have omega 3 in the right chemical form to be used by the dogs body so you need to get it from fish oil.
The recommended dosage of omega-3 for dogs varies by weight. One site suggests, “for every 30 pounds (14 Kg) of body weight, give your dog 1,000 mg fish oil containing 300 mg of EPA/DHA combined. ”
The maximum amount is said to be 1,000 mg fish oil per 10 pounds (4.5 Kg) of body weight.
My dog weigh 46 pounds (21 Kg) so about 5000 mg of fish oil.
Another dog site says that vets recommend omega 3 for the treatment of itching (pruritus), at up to 10 mg/lb of EPA each day. 46 pounds would mean 460 mg pf EPA per day.
Note most fish oil has 300 mg of omega 3 per 1000 mg capsule and that is comprised of 120g epa and 240 mg dha.
So you can see here that this other site only recommends 460/ 120 capsules or about 4 x 1000 mg capsules.
I actually give my dog about 6 capsules of Omega 3 per day with his meat based diet, and he has mostly cleared up his skin allergy.
NOTE not all dogs respond to omega 3 treatment but at least half do.
A caution on oversupplying omega 3 or omega 6
It is said that too much omega-3 and not enough omega-6 then you can decrease your dog’s immune system which is obviously what you want to avoid.
Too much omega-6 and your dog can have inflammatory issues (causing sore joints and itchy skin) and Too much omega-3 and the immune response is suppressed and then things like yeast and bacteria can take over, increasing secondary infection on top of the dog allergy caused skin itchiness.
That is why getting the right total amount of omega 6 and 3 are important.
Note in a raw diet I use sunflower oil for omega 6 (it has about 60% omega 3 in it) and I scale it up appropriately in conjunction with omega 3 fish oil. Omega 3 basically acts like a catalyst for omega 3 to do its work in soothing the skin. So without enough Omega 3, because you rely on commercial dog food flax seed, then your dog will begin to itch.
The final note is about RATIOS of omega 6 and 3
Scientific studies and articles typically show that the omega-6 to omega-3 ratios should be between about 10 to 1 and 4 to 1. (this is the ratio for high skin allergy dogs)
Many dry dog food have the ratio at 7 to 1. HOWEVER, since the flax seed oil has an inactive form of Omega 3 the ratio often spirals out of control to up to 30 or 70 to 1. If your dog has a skin allergy you do best to subsidize Omega 3 from fish oil (because the Omega 6 is adequate in dog food) and aim for a ratio down the lower end of the scale like 4 to 1.
PS dont bother with the higher expense of vet products buy human grade omega 3 in cheap pure capsules. Get ones without any additives like vitamin D or E added (as these can overdose your dog on these oily vitamins that accumulate in the dog’s body. And remember that most fish oil has only 300 mg of EPA and DHA per 1000 mg capsule, so if you are after 900 mg of Omega 3, you will have to use THREE capsules !
Consult with your vet armed with research papers to justify your opinions …