I'm assuming that it has a lot of eicosapentanoic acid, thus the name "Eicosaderm". Docosahexaenoic acid is more beneficial for your puppy's cognitive development but you want to keep things balanced.
I don't think the supplement will be of any major benefit. Fish body oil (specifically salmon) would be much more beneficial.
I use Lakse Kronch, others on this board prefer Grizzly Salmon Oil.