So, with the addition of growth hormones to the food chain getting bad press they decide to go a different route and 'enhance' feed with a "naturally occurring amino acid". Seems adding "naturally occurring" to somethings description is supposed to make it OK. It may be "naturally occurring" but it's definitely not "naturally occurring" in a fishes diet at such high levels.
Can just imagine the scene when they "discover" that adding it into the human food chain turns normal kids into hyperactive crazed monsters with 10 times the staying power of todays hyperactive crazeed monsters!