Short Communication Effects of Ammonia on Survival, Swimming and Activities of Enzymes of Nitrogen Metabolism in the Lake Magadi Tilapia Oreochromis Alcalicus Grahami
نویسندگان
چکیده
PATRICK J. WALSH1, HAROLD L. BERGMAN2, ANNIE NARAHARA2, CHRIS M. WOOD3, PATRICIA A. WRIGHT4, DAVID J. RANDALL5, J. N. MAINA6 and PIERRE LAURENT7 1Division of Marine Biology and Fisheries, Rosenstiel School of Marine and Atmospheric Science, University of Miami, Miami, FL 33149, USA, 2Department of Zoology and Physiology, University of Wyoming, Laramie, WY 82071, USA, 3Department of Biology, McMaster University, Hamilton, Ontario, Canada L8S 4K1, 4Department of Veterinary Pathology, Guelph University, Guelph, Ontario, Canada N1G 2W1, 5Department of Zoology, University of British Columbia, Vancouver, BC, Canada V6T 2A9, 6Department of Veterinary Anatomy, University of Nairobi, Chiromo Campus, Nairobi, Kenya and 7Laboratoire de Morphologie Fonctionnelle et Ultrastructurale des Adaptations, CNRS, Strasbourg, France
منابع مشابه
Respiratory Physiology of the Lake Magadi Tilapia (Oreochromis Alcalicus Grahami), a Fish Adapted to a Hot, Alkaline, and Frequently Hypoxic Environment
The tilapia Oreochromis alcalicus grahami is a unique ureotelic teleost, the only fish that lives in the alkaline hotsprings of Lake Magadi, Kenya. Physical conditions and fish behavior were monitored in the Fish Springs Lagoon area, a site where the tilapia were particularly abundant. Water Po2 and temperature fluctuated more or less in parallel in a diurnal cycle from less than 20 Torr and le...
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The Lake Magadi tilapia (Alcolapia grahami) is an unusual fish, excreting all its nitrogenous waste as urea because of its highly alkaline and buffered aquatic habitat. Here, using both physiological and molecular studies, we describe the mechanism of branchial urea excretion in this species. In vivo, repeated short-interval sampling revealed that urea excretion is continuous. The computed urea...
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The small cichlid fish Alcolapia grahami lives in Lake Magadi, Kenya, one of the most extreme aquatic environments on Earth (pH ~10, carbonate alkalinity ~300 mequiv l(-1)). The Magadi tilapia is the only 100% ureotelic teleost; it normally excretes no ammonia. This is interpreted as an evolutionary adaptation to overcome the near impossibility of sustaining an NH3 diffusion gradient across the...
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The Magadi tilapia (Alcolapia grahami, formerly Oreochromis alcalicus grahami) is a remarkable example of teleost life in an extreme environment. Typical conditions include water pH=10, titration alkalinity>300 mM, osmolality=525 mOsm, temperatures ranging from 23 degrees to 42 degrees C, and O(2) levels fluctuating diurnally between extreme hyperoxia and anoxia. A number of relatively small ti...
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