OPEN ACCESS
Fish are able to extract oxygen from water effectively and with low energy consumption. In order to understand this trait, we investigated the flow in a fish gill model. We performed particle image velocimetry measurements on an enlarged simplified model of a fish gill. Two fluid models were used in the experiments: a one-phase and a two-phase flow, the latter of which models blood flow. The local hematocrit value distribution was investigated for the two-phase flow. In addition, the flow was visualized by dye injection for both fluid models. It was concluded from the results that the effective gas exchange is due to an enhanced transversal exchange within the gill with a two-phase flow, a deformation of the erythrocytes, and a local increase in hematocrit.
energy consumption, fish, gas exchange, gill, oxygen, oxygenator, particle image velocimetry
[1] Schmidt-Nielsen, K., Animal Physiology, Cambridge University Press: Cambridge, London, New York, 1975.
[2] Froese, R. & Pauly, D., eds, Fish Base 2004. Internet publication: www.fi shbase.org, Version (10/2004).
[3] Medtronic Inc. Internet publication: www.medtronic.com/cardsurgery/arrested_heart/trillium.html, Version 08.07.
[4] Olson, K.R., Vascular anatomy of the fi sh gill. Journal of Experimental Zoology, 293, pp. 214–231, 2002.
[5] Olson, K.R., Gill circulation: regulation of perfusion distribution and metabolism of regulatory molecules. Journal of Experimental Zoology, 293, pp. 320–335, 2002.
[6] Wilson, J.M. & Laurent, P., Fish gill morphology: inside out. Journal of Experimental Zoology, 293, pp. 192–213, 2002.
[7] Srivastava, A.K. & Griffi th, R.W., Erythrocyte morphology and the ecology of species of fundulus. Copeia, 1974, pp. 136–141, 1974.
[8] Stevens, E.D., Gill morphometry of the red drum, Sciaenops ocellatus. Fish Physiology and Biochemistry, 10, pp. 169–176, 1992.
[9] Lebelo, S.L., Saunders, D.K. & Crawford, T.G., Observations on blood viscosity in striped bass, Morone saxatilis (Walbaum) associated with fi sh hatchery conditions. Transactions of the Kansas Academy of Science, 104, pp. 183–194, 2001.
[10] Adrian, R.J., Particle-imaging techniques for experimental fl uid mechanics. Annual Reviews of Fluid Mechanics, 23, pp. 261–304, 1991.