Abstract
1. Rates of oxygen consumption and carbon dioxide production were measured in pigs from birth to 3 days of age in an open-circuit system.2. The mean respiratory quotient (RQ) during the first 6 h following birth was 0.95 in fasted pigs and 0.91 in pigs which were allowed to feed.3. The RQ fell during the remainder of the first postnatal day to mean values close to 0.85, whether the pigs were allowed to feed from birth or were fasted.4. From 1 to 3 days of age the RQ had a mean value of 0.79.5. There was little difference in the RQ of pigs exposed to environmental temperatures of either 32 or 16°.6. It is concluded that the baby pig is not exclusively dependent on carbohydrate for its energy metabolism.