Sublethal effects of aquatic pollution in Lake Maryut on the African sharptooth catfish, Clarias gariepinus (Burchell, 1822)

Abstract

Some aspects of the physiology and biochemistry of the African sharptooth catfish, Clarias gariepinus (Burchell, 1822), were studied along with an array of physicochemical characteristics of the water in Lake Maryût, Egypt. Data were compared to those of a reference fish hatchery. At least 11 of the conventional water pollutants (Cd, Cu, Fe, Pb, Mn, Hg, Ni, Zn, turbidity, chemical oxygen demand and ammonia nitrogen) were elevated in the most polluted main basin of the lake. In turn, serologic analysis of the indigenous catfish C. gariepinus pointed at functional impairment of the liver, heart and kidney as reflected by the elevated activities of alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, creatine kinase, cholinesterase, glucose and creatinine. Reduced nucleic acid measurements [the ratio RNA/DNA and the relative RNA content (r)] indicated diminished protein synthesis and impaired growth in polluted fish. In some instances, glucose and nucleic acid measures were elevated in favour of fish from moderately polluted basins of the lake rather than in reference fish. Fish seemed to profit from the typical geographical habitat in the lake, regardless of the virtual contamination there, versus reference fish that seemed to suffer congestion stress and food competition in the confined and overcrowded commercial pond.

Biochemical alterations induced by Zn and Cd individually or in combination in the serum of Oreochromis niloticus

“…In our work, decreased activity of serum ChE, which shows the hipocholinesterasemia, may be the consequence of induced-liver dysfunction due to heavy metal toxicity. The present finding is in agreement with the observation of Adham (2002) who found that serum ChE activity decreased in Clarias gariepinus in water polluted by, especially, heavy metals (Cd, Pb, Mn, Hg, Ni). The researcher concluded that ChE is synthesized by liver cells, which might be chronically injured in C. gariepinus due to water pollution.…”

Histopathological and biochemical changes in the liver, kidney, and bloodof amphibians intoxicated with cadmium

“…With respect to this parameter, Adham (2002) found high serum creatinine values in populations of fish (C. gariepinus) living in polluted environments. These values have been associated with a physiological imbalance due to renal failure and/or an increase in the catabolism of the muscle tissue.…”

Acute toxicity of the pesticide methomyl on the topmouth gudgeon (Pseudorasbora parva): mortality and effects on four biomarkers

“…Transaminases GOT and GPT are liver-specific enzymes, which are a more sensitive measure of hepatotoxicity and histopathalogic changes, can be assessed within a shorter time in teleost fish (Balint et al1997). Increases or decreases in GOT and GPT activity levels are suggested as reflecting tissue damage in liver, kidney, and gill (Oluah 1999;Venkateswara 2006a, b) and in liver disfunction (Adham 2002). The liver GOT enzyme activity of fish exposed to 0.043-0.142 mg/l of methomyl showed a declining tendency at 24 h. Venkateswara (2006a, b) also observed decreased transaminase activity (GPT and GOT) in liver and gill of tilapia, Oreochromis mossambicus, exposed to 0.017 mg/l of novel organophosphorus insecticides, 2-butenoic acid-3-(diethoxyphosphinothioyl) methyl ester (RPR-II), and 1.15 mg/l of monocrotophos, respectively.…”