I am unafraid of animal fats. Why? Well, for one they don't really cause any lipid issues on a low carb diet. In fact, they raise the amount of good cholesterol. For another, I don't really buy into the whole lipid hypothesis of heart disease, in it's present form. Read Gary Taubes "Good Calories, Bad Calories" if you want a good overview of the source of my skepticism. This topic has become dogmatic though. Many people have invested their careers, reputations and fortunes in promoting the idea that fat is bad or animal proteins are harmful to humans. Arguing with them is like trying to use science to prove God does or does not exist. It just doesn't work. But everyone is free to choose their phat philosophy. And my philosophy is that fatliness is next to godliness.
I absolutely love duck and goose fat and I cook those birds just to rob them of their fat. It is great tasting fat. Veggies cooked in it are just amazing tasting. Also these birds eat a lot of grasses and probably insects, both are great sources of omega-3 fatty acids, so it wouldn't surprise me if duck and goose are higher in those fatty acids. But outside of my suspicion they're very healthful forms of fat, I think they're vastly delicious.
Do yourself a favor, roast a duck or goose and save its fat for cooking!
Here's a recipe that should get you started, I use this method and it works great. I skim the fat from the pan and save it.
Crisp Roast Duck Recipe