Studies on Energy Metabolism in the Fowl
II. Metabolism in Fasting Condition
1964 Volume 35 Issue 1 Pages 18-25
Details
1964 Volume 35 Issue 1 Pages 18-25
Energy and gaseous metabolism was determined in 7-to 8-month-old White Leghorn cockerels under fasting conditions by using a respiration apparatus designed by the authors (Japanese J. Zootechn. Sci. 35: P.11, 1964). The following results were obtained.
(1) The following factors were determined to compute the gaseous exchange and heat production in the metabolism of muscular-tissue protein: One gram of urinary nitrogen corresponding to 5.44 litters of respiratory oxygen and producing 3.96 liters of carbon dioxide and 23.48Cal.
(2) In computing the total heat production in the birds, LUSK's and BENEDICT's methods agreed comparatively well in results. The difference in value between these methods was less than 2 per cent.
(3) The heat produced from the protein and the fat catabolism in the birds was about 10 and 90%, respectively, of the total heat produced.
(4) Heat production, oxygen consumption, and carbon dioxide elimination in the birds showed a typical diurnal rhythm. Their values were high at 8-12a.m., and low at 8-12 p.m., and became high again at 8-12a.m. on the next day. The mid-point of the rhythm was either at 4p.m. or at 4a.m.
(5) In chicks which had been under nutritionally balanced conditions, a fast for 32-36 hours was required before the heating effect of a feed given prior to the fasting disappeared. After that period of fasting, the respiratory quotient, O2 thermal quotient, and CO2 thermal quotient reached a constant level, which was 0.717, 4.69Cal and 6.55Cal., respectively.
(6) The average heat production in 6 cockerels was 67.2Cal. per day per kilogram of body weight, or 80.8Cal. per day per (kg)0.73 of body weight, on the second day of fasting and 63.0 and 73.2Cal., respectively, on the third day. Taking the heat effect of a feed given prior to the fasting into consideration, the values on the third day deemed to be those of the basal heat production. They were 15% higher than those determined in meat-type chicks.
