I've wondered if feed is lacking particularly in the nutrition required to grow fish in the dimension of length. Certainly, feed grows LMB and when preferred foods like fish are unavailable. Feed grows them much faster than a diet of crustaceans and insects as Jim's work shows.
I think it would be great to understand how the improvements in the feed formulation may have allowed or encouraged changes in feeding strategy. For example, were the feed rates in terms of pounds of feed continued at the prior rate? Or did the increased concentration of beneficial nutrients allow a reduced feed rate? Or perhaps did it alter the strategy by encouraging an increase in feed rate where fish grew longer faster albeit with less obesity.
From a feed supplier perspective, I wouldn't want to increase the cost of feed if I could if for no other reason to keep it affordable for those depending on it. We understand how the feed has improved the condition of fish, it would be useful to understand whether growth rates in weight and length were improved or to what extent these may have been sacrificed to produce healthier fish.
It isn't what we don't know that gives us trouble, it's what we know that ain't so - Will Rogers
