| one publication added to basket [260670] | Temperature effects on the metabolism of larvae of the Antarctic starfish Odontaster validus, using a novel micro-respirometry method
Peck, L.S.; Prothero-Thomas, E. (2002). Temperature effects on the metabolism of larvae of the Antarctic starfish Odontaster validus, using a novel micro-respirometry method. Mar. Biol. (Berl.) 141(2): 271-276. http://dx.doi.org/10.1007/s00227-002-0834-5
In: Marine Biology: International Journal on Life in Oceans and Coastal Waters. Springer: Heidelberg; Berlin. ISSN 0025-3162; e-ISSN 1432-1793, more
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| Authors | | Top |
- Peck, L.S.
- Prothero-Thomas, E.
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| Abstract |
Oxygen consumption of individual larvae of the Antarctic sea-star Odontaster validus was measured during the 50-day period following fertilisation. Values ranged from 0.76 pmol O2 h–1 for one specimen at the coeloblastula stage to 77.6 pmol O2 h–1 for one bipinnaria larva. At 0°C the mean oxygen consumption rate of an individual larva increased from 10.9 pmol O2 h–1 (standard error of the mean, SEM, 0.13) for a gastrula larva, 13 days post-fertilisation, to 25.4 pmol O2 h–1 (SEM 3.5) at the bipinnaria stage (50 days post-fertilisation). Gastrulae reared at –0.5°C did not have significantly different oxygen consumption rates between days 13 and 45 post-fertilisation (mean=11.4 pmol O2 h–1). Individual metabolic rates were highly variable, covering more than a 40-fold range. At 2°C gastrula oxygen consumption was on average 45% higher (17.35 pmol O2 h–1), giving a Q10 temperature effect of 4.4. For bipinnaria, mean oxygen consumption in 2°C larvae (31.4 pmol O2 h–1) was not significantly different from that in larvae at –0.5°C, suggesting bipinnaria metabolism may be less sensitive to temperature change than earlier stages. At 2°C the bipinnaria stage was reached at 30–35 days compared with 45–50 days at 0°C, giving a Q10 of 4.5 for temperature effects on development. The method here used a new, highly sensitive micro-respirometry method that is inexpensive and straightforward in design. Individual larvae of O. validus were held in 35- to 50-µl respirometers. These larvae have very low metabolic rates, and published work on such organisms have utilised at least 25 individuals per chamber. The oxygen content of the respirometers was measured using a 25-µl sample injected into a couloximeter. Oxygen consumption rates down to –1 pmol h–1 can be detected. Under optimum conditions oxygen consumption of a single larva of –4 pmol O2 h–1 was measured with an accuracy of ±20%. Values of ~15 pmol h–1 could routinely be measured with this accuracy. This method would allow oxygen consumption to be evaluated in individual field-caught larvae of most marine ectotherms. |
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