The effects of mass, temperature and molting on the respiration of Macropetasma africanus balss (Decapoda: Penaeoidea)

Abstract 1. 1. The effects of mass, temperature and molting on the respiration of the surf zone penaeid Macropetasma africanus were examined using a flow through system. 2. 2. Respiration (ascribed to routine metabolism) is described by a power curve: R = aM b ( R = μ gO 2 hr −1 , M = mg dry mass), which gives values of a = 1.806, 2.164, 2.964, 3.964, 3.599 and 4.592, and b = 0.799, 0.880, 0.857, 0.840 and 0.959 at 15, 17, 20, 22 and 25°C, respectively. 3. 3. The expression R = 0.0115 T 1.858 M 0.847 provides a reasonable prediction of respiration as a combined function of prawn size and temperature ( T ,°C). 4. 4. In response to approaching ecdysis the oxygen consumption remains at an elevated level until 5 hr before molting followed by a rapid increase reaching a peak at molting. Oxygen consumption decreases rapidly after molting.