Time Course Changes in 13C Enrichment of Respiratory CO2 in Chickens Intravenously Single-Injected with [1-13C] Sodium Acetate

Time course changes in 13C enrichment of respiratory CO2 in young chickens intravenously injected with [1-13C] sodium acetate were examined to clarify the rapidity of oxidation of intravenous acetate to CO2 in chicken body. The 13C enrichment reached the peak level within 20-30 minutes after single intravenous injection with 1 ml of 1% [1-13C] sodium acetate and returned to the initial level by 180 minutes. On the other hand, no change in 13C enrichment of respiratory CO2 was observed in control chicks injected with saline throughout the experimental period. The recovery of the injected [1-13C] sodium acetate was estimated to be 47.0%. These results indicate that intravenously injected acetate into young chickens is rapidly metabolized to CO2 and suggest a rapid use of cecal acetate as an energy source in chickens.