QUICK SEARCH:   [advanced] Author: Keyword(s):
Home     Help     Feedback     Subscriptions     Archive     Search     Table of Contents

First published online March 16, 2007
Journal of Experimental Biology 210, 1109-1115 (2007)
Published by The Company of Biologists 2007
doi: 10.1242/jeb.002238

This Article Figures Only Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Ong, K. J. Articles by Wright, P. A. Search for Related Content PubMed PubMed Citation Articles by Ong, K. J. Articles by Wright, P. A. Social Bookmarking                         What's this?

Gill morphology of the mangrove killifish (Kryptolebias marmoratus) is plastic and changes in response to terrestrial air exposure

K. J. Ong, E. D. Stevens and P. A. Wright^*

Department of Integrative Biology, University of Guelph, Guelph, Ontario, N1G 2W1, Canada

^* Author for correspondence (e-mail: patwrigh{at}uoguelph.ca)

Accepted 29 January 2007

Amphibious mangrove killifish, Kryptolebias marmoratus (formerly Rivulus marmoratus), are frequently exposed to aerial conditions in their natural environment. We tested the hypothesis that gill structure is plastic and that metabolic rate is maintained in response to air exposure. During air exposure, when gills are no longer functional, we predicted that gill surface area would decrease. In the first experiment, K. marmoratus were exposed to either water (control) or air for 1 h, 1 day, 1 week, or 1 week followed by a return to water for 1 week (recovery). Scanning electron micrographs (SEM) and light micrographs of gill sections were taken, and morphometric analyses of lamellar width, lamellar length and interlamellar cell mass (ILCM) height were performed. Following 1 week of air exposure, SEM indicated that there was a decrease in lamellar surface area. Morphometric analysis of light micrographs revealed that there were significant changes in the height of the ILCM, but there were no significant differences in lamellae width and length between any of the treatments. Following 1 week of recovery in water, the ILCM regressed and gill lamellae were similar to control fish, indicating that the morphological changes were reversible. In the second experiment, _CO2 was measured in fish continuously over a 5-day period in air and compared with previous measurements of oxygen uptake (_O2) in water. _CO2 varied between 6 and 10 µmol g^–1 h^–1 and was significantly higher on days 3, 4 and 5 relative to days 1 and 2. In contrast to _O2 in water, _CO2 in air showed no diurnal rhythm over a 24 h period. These findings indicate that K. marmoratus remodel their gill structures in response to air exposure and that these changes are completely reversible. Furthermore, over a similar time frame, changes in _CO2 indicate that metabolic rate is maintained at a rate comparable to that of fish in water, underlying the remarkable ability of K. marmoratus to thrive in both aquatic and terrestrial habitats.

Key words: metabolic rate, CO₂ excretion, emersion, gill lamellae, interlamellar cell mass

CiteULike    Complore    Connotea    Del.icio.us    Digg    Reddit    Technorati    Twitter    What's this?

This article has been cited by other articles:

				D. Mitrovic and S. F. Perry The effects of thermally induced gill remodeling on ionocyte distribution and branchial chloride fluxes in goldfish (Carassius auratus) J. Exp. Biol., March 15, 2009; 212(6): 843 - 852. [Abstract] [Full Text] [PDF]

				S. F. Perry A FIRST LOOK AT HOW FISH GILLS WORK J. Exp. Biol., November 15, 2008; 211(22): 3519 - 3521. [Full Text] [PDF]

				T.-C. Kuo Methylmercury Induces Alveolar Macrophages Apoptosis International Journal of Toxicology, May 1, 2008; 27(3): 257 - 263. [Abstract] [Full Text] [PDF]

				V. Matey, J. G. Richards, Y. Wang, C. M. Wood, J. Rogers, R. Davies, B. W. Murray, X.-Q. Chen, J. Du, and C. J. Brauner The effect of hypoxia on gill morphology and ionoregulatory status in the Lake Qinghai scaleless carp, Gymnocypris przewalskii J. Exp. Biol., April 1, 2008; 211(7): 1063 - 1074. [Abstract] [Full Text] [PDF]

				G. E. Nilsson Gill remodeling in fish - a new fashion or an ancient secret? J. Exp. Biol., July 15, 2007; 210(14): 2403 - 2409. [Abstract] [Full Text] [PDF]

				C. Y. C. Hung, K. N. T. Tsui, J. M. Wilson, C. M. Nawata, C. M. Wood, and P. A. Wright Rhesus glycoprotein gene expression in the mangrove killifish Kryptolebias marmoratus exposed to elevated environmental ammonia levels and air J. Exp. Biol., July 15, 2007; 210(14): 2419 - 2429. [Abstract] [Full Text] [PDF]