Starvation-induced ketone body production in the conscious unrestrained miniature pig.

The effects of short-term starvation (up to 5 days) on hepatic ketone body production was investigated in the conscious unrestrained miniature pig in vivo. Starvation induced an increase in arterial free fatty acid concentration (0.2-0.7 mM) with a concomitant elevation in hepatic free fatty acid extraction [-1.4-5.7 mumol/kg. minute),r = 0.53, P less than 0.005]. Ketone body production (sum of acetoacetate + beta-hydroxybutyrate) increased from 1.5 to 5.8 mumol/(kg . minute) in parallel (r = 0.71, P less than 0.0005). During starvation arterial insulin levels decreased, glucagon increased, cortisol remained unchanged and a "low T3 state' was observed. These data differ in some aspects from those reported for humans and dogs. Thus a species-specific variation in the fuel economy of the pig's body is proposed.