Fish oil for my shetland sheepdog?

Speak to your vet first - you want to make sure not to add fat to the diet of a dog that could be at risk for pancreatitis. However, so long as that is not a concern, you are absolutely on the right track. Fish oil strengthens the cell walls, and therefore will help with the food allergies and inflammation associated with allergic reactions. Often the fish oil you get at the grocery store is just fine, and so remember that most dog food is saturated with 'tocopherols', which is vitamin E - you are right, they need the right mix of omega-6 and omega-3 for it to be used, but the omega-6 is very often already there. All you need is some two for the price of one fish oil capsules.