Fish oil is rich in two essential fatty acids: EPA (Eicosapentaenoic acid) and DHA (Docosahexaenoic acid). These two fatty acids from the Omega 3 (n-3) series are considered essential because they must be provided in the diet.
Fish oil has more than triple the amount of EPA and DHA than salmon oil with 18% EPA and 12% DHA vs 3.5% EPA and 4% DHA in salmon oil.
Omega 3 deficiency symptoms include: flaky skin, dull coat, itching, increased shedding, poor wound healing, liver disorders, problems with the reproductive system, poor vision and memory loss. Over time, the skin becomes pruritic, greasy and susceptible to infection, otitis externa and interdigital exudation has also been reported in EFA-deficient dogs and cats, the latter also developing fatty livers and kidneys.
During pregnancy and lactation, female cats and dogs have greater requirements for n-3 fatty acids, and deficiency can lead to failure in delivering healthy offspring. Puppies and kittens require omega 3 for normal growth and development.
Finally, omega 3 fatty acids are absolutely essential for normal inflammatory and allergic response, and has been found to reduce inflammation in arthritic conditions.