Physiological evaluation of temperature effect on the growth processes of the mysid, Neomysis intermedia Czerniawsky

Abstract

Ingestion, respiration, and molting loss rates were measured over the 3 – 29°C range in Neomysis intermedia . Weight specific rates of these physiological processes ranged from 2 to 140% body C day ⁻¹ for ingestion, from 2 to 15% body C day ⁻¹ for respiration, and from 0.1 to 5% body C day ⁻¹ for molting loss. All weight-specific rates showed a logarithmic decrease with a logarithmic increase in body weight, and a logarithmic increase with a linear increase in temperature below 20 or 25°C. The effect of temperature, however, was different between the physiological rates, with a large temperature dependency for ingestion ( Q₁₀ = 2.6 –3.9) and molting loss ( Q¹⁰ = 2.9 – 3.6) and a moderate temperature dependency for respiration ( Q₁₀ = 1.9 – 2.1). Calculated assimilation efficiency changed with body size, but was constant over the temperature range examined. Allocation of assimilated materials varied with a change in temperature, reflecting the different temperature dependence between physiological processes. It was deduced that the strong temperature dependency of the growth rate in N. intermedia observed in the previous studies resulted from the large temperature effect on ingestion and assimilation rates, superimposed by the different allocation of assimilated materials.