Feed typically accounts for about 70% of the cost of production. It is therefore very important to choose wisely. A higher price per kilogram of feed usually has a disproportionaly positive impact of growth rate and feed conversion efficiency. Except when it doesn't. We use eight cages to test four brands of feed over the period of a month or so. Start and end weights are recorded so we can see which feed promotes the fastest growth. And more importantly, total feed given is divided by biomass increase to give us the FCR (Feed Conversion Ratio).
Subjects are rounded up periodically to be weighed and re-counted