Well, if my experience in the last few weeks is any indicator, I'd say Legbars and Legbar crosses is one of them. I've been feeding Layena "with Omega-3's" for the past six weeks or so, but since most of my eggs are actually used in baking, hadn't really noticed anything. Tried boiling a couple for the first time the other day, and had to throw them out. Thought they were just "old" although the dates indicated only 3 weeks. So, tried boiling a couple of laid-that-day-eggs (peeling those was fun, I can tell you,) and when they had the same funky taste, started googling "fishy tasting eggs." To be quite fair, this is the first I've heard of it.