The Influence of Starvation on Temperature Relationships of Metabolism in Ectotherms

Abstract

Although nutritional factors are well known to influence the level of metabolism in ectotherms, comparatively few studies have taken this factor into account during thermal acclimation. Dehnel (1960) for example studied the effect of temperature and salinity on the oxygen consumption of Hemigrapsus oregonensis and H. nudus which had been starved during the acclimation period. A similar practice has been adopted in most other studies on thermal acclimation, especially in Crustacea, where it is known that starvation prevents the onset of moulting. Roberts (1957) studied the influence of starvation and moulting in the metabolic acclimatory response of Pachygrapsus crassipes and reported that the rate of oxygen consumption of starved crabs was approximately 60% of that in animals which had been fed on liver. Barnes, Barnes and Finlayson (1963a) have demonstrated that respiration in the barnacle Balanus balanoides varies according to the nutritional state of the animal. Davies (1966, 1967) showed that the metabolic rate could be correlated with the availability of food because the oxygen consumption of Patella vulgata collected from bare rock surfaces on the upper shore was low compared with that of limpets collected from the mud shore near algae. In the pulmonate Arianta arbustorum, starved specimens had a lower oxygen consumption than well-fed ones and if starvation was continued for 4 days then the rate fell to the aestivation level (Nopp, 1965). This effect has also been observed in the isolated tissue of hepatopancreas and gonad following several weeks starvation (Nopp and Farahat, 1967).