Question on info on fatty acids in "Nourishing Traditions"

In "Nourishing Traditions," Sally Fallon writes this on "very-long-chain fatty acids:"

"Some people can make these fatty acids from EFAs, but others, particularly those whose ancestors ate a lot of fish, lack enzymes to produce them. These 'obligate carnivores' must obtain elongated fatty acids from animal foods like organ meats, egg yolks, butter and fish oils."

She goes on to say that some of the most important "very-long-chain fatty acids" are DGLA, AA, EPA, and DHA.

What I am wondering is this: are high-vitamin butter and cod liver oil a source of these types of fatty acids and would consuming high-vitamin butter oil and cod liver oil cover my bases as far as getting enough of them if we consider that my ancestors ate a lot of fish? Tweet