... labelled water (DLW) method when measuring energy expenditure in animals with access to freshwater. Seasonal changes in the background levels of deuterium and oxygen-18 in the body water of four captive harp seals and in the freshwater pool in which they were kept were measured over a time period of 1 year...

...%and 6.14±0.65% TBW day –1 , respectively. Water turnover in fasted turtles was 36% lower than that of fed turtles but MR (from oxygen consumption) of fasted turtles (13.77±1.49 kJ kg –1 day –1 ) was 52% lower than in fed turtles (28.66±5.31 kJ kg –1 day –1 ). Deuterium to oxygen-18 turnover rate (k d :k o...

... concentrations of deuterium and 18 O and withdrew 1–2 μ l of haemolymph to determine initial 18 O concentration. The injected isotopes were equilibrated with the body water pool after 10 min, and high material turnover allowed the analysis of final blood isotope concentrations after 5–7 h. On average ( n =16...