Effect of body size, temperature and starvation on oxygen consumption of antarctic krill Euphausia superba

• Main Authors: Ngan, Phan Van, Gomes, Vicente, Carvalho, Paulo S. M., Passos, Maria José de A. C. R.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Universidade de São Paulo. Instituto Oceanográfico 1997
• Subjects: Consumo de oxigênio; Krill; Metabolismo; Antártica; Euphausia superba; Temperatura; Jejum; Oxygen consumption; Metabolism; Antarctica; Temperature; Starvation; Antarctic; Antarc*; Antarctic Krill
• Online Access: https://www.revistas.usp.br/rbo/article/view/6818

Routine oxygen consumption of krill was investigated as a general measure of its metabolism and assesses the effects of body size, temperature and starvation on the metabolism. No significant difference in whole animal consllmption was detected after 1,3,5 and 7 days of starvation. The response of metabolism of krill to temperature shows a zone of independence, from 0 to 1°C in which the temperature exerts no effect on metabolism. From 1 to 4°C the metabolism increases rapidly in function of temperature. There was a general increase in oxygen consumption with increasing body wet weight. The equation 'between consumption and wet weight is given by Log Q02 = 2.061+ 0.987xLogW, with r = 0.86. The slope of the regression line b=0.987 is less than unity, indicating that oxygen consllmption per unit weight is greater for the smaller than for the larger krill. Average metabolic rate at O°C of 164 krill is 733.24 l, µlO2g(dry wt)-1h-1. The metabolic rate is of 1129.67 J- µlO2g(dry wt)-1h-1 for small krill (13-19 mg dry weight) and 636.16 J- µlO2g(dry wt)-1h-1 for larger animais (160-169 mg dry weight). The metabülism ofkrill is shown to be related to period of adaptation and types of respirometer. Prolonged adaptation period showed adverse effect on metabolism and average oxygen consumption is almost three times higher in respirometers with stirring device than in simple sealed chambers. O consumo de oxigênio de rotina de krll foi avaliado como uma forma de mensurar seu metabolismo e determinar os efeitos do tamanho, da temperatura e do jejum sobre o mesmo. Não foram detectadas diferenças significativas no consumo total do animal após 1, 3, 5 e 7 dias de jejum. As respostas do metabolismo de krill em função da variação da temperatura demonstraram a existência de uma faixa de independência, de O°Ca 1°C, na qual a temperatura não exerce nenhum efeito sobre o metabolismo. De 1°C a 4°C o metabolismo aumenta rapidamente em função da temperatura. Houve um aumento significativo no consumo de oxigênio em função do peso. A ...