Pakistan Journal of Biological Sciences1028-88801812-5735Asian Network for Scientific Information10.3923/pjbs.2006.2215.2221Cyprinus carpio) at Different pH Levels]]>AbbasHossam H.122006912The toxicity (LC50) of total and un-ionized ammonia was tested on different sizes (5, 10, 15 g) of common carp Cyprinus carpio maintained at three different pH levels within the range of 6.5-8.5. Within the same pH, the toxic effect of ammonia was independent of fish size. In addition, the toxicity of un-ionized ammonia increased at lower pH. However, total ammonia exerts some measure of toxicity and/or increased H+ concentration increases the toxicity of un-ionized ammonia. Common carp fingerlings (15 g) were exposed to the 96 h LC50 of un-ionized ammonia (0.93 mg NH3-N/L) at pH 7.5. Changes in hemoglobin (Hb), hematocrit (Ht), sodium (Na+), potassium (K+), glucose, aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) were recorded. Blood Hb decreased after 6 and 96 h of exposure while Ht decreased after 3 h of exposure. Serum Na+ and K+ increased during the experimental period (96 h). Glucose concentration increased initially and then returned to less than the control value after 96 h of exposure. There was a significant decrease in AST, ALT and LDH activities after 6 h of exposure, after which enzyme activity increased until the end of the experimental period.]]>Abel, P.D.,19982nd Edn.,Ahmed, N.A., S.S. El-Serafy, A.A.M. El-Shafey and N.A.H. Abdelhamide, 1992Oreochromis niloticus. ]]>1992pp: 155160Alabaster, J.S. and R. Lloyd, 1980APHA (American Public Health Association),199519th Edn.,Bader, J.A.,1990Ictalurus punctatus. ]]>1990Boyd, C.E.,1990Buckley, J.A., C.M. Vitmore and B.D. Liming,1979Onchorhyncus kisutch. ]]>63297303Chatty, C.S., R.C. Naidu, Y.S. Reddy, P. Arnua and D.S. Swan, 1980Tilapia mossambica subjected to ammonia toxicity. ]]>27177182Chew, S.F., L.N. Hong, J.M. Wilson and D.J. Randall, 2003Periophthalmodon schlosseri but inhibits ammonia excretion in the related species Boleophthalmus boddaerti. ]]>76204212Dosdat, A., J.P. Le Ruyet, D. Coves, G. Dutto, E. Gasset, A. Le Roux and G. Lemarie, 2003Dicentrarchus labrax. ]]>16509520El-Nagar, G.O., M.A.S. El-Deen and H.H.H. Abbas,2001Oreochromis aureus and African catfish Clarias gariepinus exposed to copper and lead.]]>34225244Emerson, K., R.C. Russo, R.E. Lund and R.V. Thurston,19753223792383Erickson, R.J., 19851910471058Fernandez, F.J. and H.L. Khan,197132434Harry, V.D. and C.E. Boyd, 198749260263Hattingh, H.J.,1976Labeo capensis (Smith).]]>10191195Haux, C. and A. Larsson,1982Salmo gairdneri. ]]>62834Heath, A.G., 1987Lauran, D.J. and D.G. McDonald,1985Salmo gairdneri Richardson.]]>155635644Maetz, J. and F.R. Garcia,1964Carassius auratus. Evidence for NH4+/ Na + and HCo3G/ClG exchanges.]]>4712091226Maetz, J., 1973 + /NH4 +, Na + /H + exchanges and NH3 movement across the gill of Carassius auratus. ]]>58255275Wood, C.M.,19931993pp: 379-425pp: 379-425Mazhar, F.M., M.A. Ashry and M.M. Fathalla,1987Clarias lazera (C. and V.) 1. Mortality rates and hematological studies.]]>14363372Niels, E.V., B. Korsgaard and F.B. Jenson,1998Oncorhynchus mykiss effects on electrolyte status, blood respiratory properties and brain glutamine glutamate concentrations.]]>41325342Reitman, S. and S. Frankel,1957285663Russo, R.C., 19851985pp: 455-471pp: 455-471Salah El-Deen, M.A. and W.A. Rogers, 19935280286Salah El-Deen, M.A., 1999Ctenopharyngodon idella at different pH levels. ]]>33219235Sampaio, L.A., W. Wasielesky and K.C. Miranda-Filho, 2002Mugil platanus. ]]>68668674Selye, H.,197361693699Sheehan, R.J. and W.M. Lewis,1986115891899Smart, G., 1978Salmo gairdeneri exposed to acutely lethal concentrations. ]]>1293104Smith, L.S., 1982Solorzano, L.,196914799801Thurston, R.V., R.C. Russo and C.E. Smith, 1978107361368Thurston, R.V., R.C. Russo and G.A. Vinogradov, 198115837840Thurston, R.V. and R.C. Russo, 1983112696704Thurston, R.V., R.C. Russo and G.R. Phillips, 1983112705711Thurston, R.V., R.J. Russo, R.J. Luedtke, C.E. Smith and E.L. Meyn et al.,19841135673Thurston, R.V., R.C. Russo, E.L. Meyn, R.K. Zajdel and C.E. Smith, 1986115196207Trinder, P., 196962424Tulasi, S.J., R. Yasmeen and J.V. Rao,1990Barytelphusa guerini exposed to sublethal concentrations of lead acetate and lead nitrate. ]]>11163168Weis, J.S., P. Weis, M. Heber and S.V. Amid,1981Fundulus heteroclitus embryos from polluted vs. non-polluted environment. ]]>65283287Wicks, B.J. and D.J. Randall, 2002Oncorhynchus mykiss. ]]>597182Yamagata, Y. and M. Niwa, 1982 Anguila japonica.]]>44171176Zijlstra, N.C., 19615719720USEPA.,19991999USEPA.,20022002SAS.,20002000Mazhar, F.M., M.A. Ashry and S.M. Kadry,1987Clarias lazera.]]>13247256