A calorimetric estimate of the efficiency of utilisation of dietary energy by the growing cockerel

Abstract

The metabolic rates of four growing cockerels, aged between 10 and 18 weeks, were measured using respiration calorimetry. Measurements were made when the birds had been fasted for 48–72 h and when they had been given a cereal‐type diet at maintenance and production levels. The mean fasting heat production (±SE) was 92.3 (±5.0) kcal/kg d or 113.4 (±5.7) kcal/kg3/4 d. The relationship between energy balance (T) and ME intake (X) was calculated to be Y = 0.851X—92.9 indicating that the maintenance ME requirement was 109.1 kcal/kg d and that the net availability of the ME was 85.1 per cent. The efficiency of energy utilisation in relation to plane of nutrition and to the amount of protein and fat deposited is discussed.