Efficiency of energy utilization by the Zucker hereditarily obese rat "fatty" (38569)

The hereditarily obese rat "fatty", with food intake restricted to approximately normal, laid down excessive fat at the rate of 0.56 g rat per day for up to 74 days on experiment, producing an energy denser, but lighter weight, carcass than the normal control. The "fatty" retained over 20% of the energy supplied, in its carcass, the control less than 10%.