Seasonal variations in tissue metabolic capacities of yellow perch (Perca flavescens) from clean and metal-contaminated environments

Abstract

This study examined seasonal variations in tissue metal contamination and physiological condition of yellow perch (Perca flavescens) from a clean lake (Halfway Lake) and a metal-contaminated environment (Whitson Lake) in spring, summer, and fall of 1999. Dietary metal content influenced liver metal concentrations, especially for cadmium. Fulton's condition factor (FCF), an indicator of recent feeding activity, was lower in Whitson fish except in summer, when higher FCF values corresponded with higher liver copper concentrations, presumably because of higher feeding rate. Tissue protein concentrations and indicators of biosynthetic capacities (nucleoside diphosphate kinase and RNA/DNA ratios) suggested lower biosynthesis in Whitson fish. Muscle aerobic and anaerobic capacities (using citrate synthase and lactate dehydrogenase as indicators, respectively) were consistently lower in Whitson fish, with maximal differences in summer. In contrast, although liver aerobic capacities were generally comparable among populations, anaerobic capacities were much higher in Whitson fish. Finally, gill sodium/potassium adenosinetriphosphatase (Na + /K + ATPase) activity peaked in the spring in fish from both lakes, and higher activities were correlated with elevated gill copper concentrations. This study highlights the importance of seasonal variations in tissue metal concentrations and fish condition. This information is essential to evaluate the extent of impairment in condition faced by metalcontaminated wild fish.Résumé : Nous avons examiné les variations saisonnières de la contamination des tissus par les métaux et de la condition physiologique de perchaudes (Perca flavescens) d'un milieu propre (lac Halfway) et d'un milieu contaminé par les métaux (lac Whitson) au printemps, à l'été et à l'automne 1999. Le contenu en métaux du régime alimentaire influence la concentration hépatique des métaux, en particulier du cadmium. Le coefficient de condition de Fulton (FCF), un indicateur d'activité alimentaire récente, est plus bas chez les poissons du lac Whitson, sauf en été, lorsque les valeurs plus élevées de FCF correspondent à des concentrations plus élevées de cuivre hépatique, sans doute à cause d'un taux d'alimentation plus grand. Les concentrations tissulaires de protéines et les indicateurs du potentiel de biosynthèse (la nucléoside diphosphate kinase et les rapports ARN/ADN) laissent croire à une réduction de la biosynthèse chez les poissons du lac Whitston. Les capacités musculaires aérobies et anaérobies (mesurées respectivement d'après les concentrations de citrate synthase et de lactate déshydrogénase) sont toujours plus basses chez les poissons du lac Whitson et les écarts sont maximaux en été. En revanche, bien que les capacités hépatiques aérobies soient, en général, semblables chez les deux populations, les capacités anaérobies sont beaucoup plus fortes chez les poissons du lac Whitson. Enfin, l'activité de la sodium/potassium adénosinetriphosphatase (ATPase) dans les branchies est maximale au printemps chez les ...

Effects of Cu on plasma cortisol and cortisol secretion by adrenocortical cells of rainbow trout (Oncorhynchus mykiss)

“…Moreover, Cu concentrations in livers of trout exposed to the higher concentration (80 g/l) were similar to levels reported by Laflamme et al (2000) in perch from field studies in the mining area of Abitibi, Qc. Similar to other laboratory and field studies, liver was the principal organ of Cu accumulation, followed by other tissues (McGeer et al, 2000b;Audet and Couture, 2003;Lévesque et al, 2003;Giguere et al, 2004).…”

“…Chronic exposures however led to either a return to normal activity of the gill Na + /K + -ATPase (Laurén and McDonald, 1987) or an increase (McGeer et al, 2000a). Field studies with yellow perch sampled in lakes contaminated by mixtures of metals, including Cu, reported both lower activities (Lévesque et al, 2003) and higher activities (Audet and Couture, 2003), compared to reference fish. Our results with rainbow trout exposed in the laboratory indicate that a 30 day exposure to 30 or 80 g/l of Cu inhibits the activity of gill Na + /K + -ATPase, possibly because the fish were not fully acclimated to the metal.…”

Live Fast and Die Young: Metal Effects on Condition and Physiology of Wild Yellow Perch from along Two Metal Contamination Gradients

“…2000; Sherwood et al 2002), intermediary metabolism (Levesque et al 2002), aerobic metabolism (Rajotte and Couture 2002;Audet and Couture 2003;Couture and Kumar 2003), and even basic morphometric condition indicators (Laflamme et al 2000;Levesque et al 2002;Pyle et al 2005;Couture et al 2008b). Although this substantial literature leaves little doubt that metals affect the condition of wild yellow perch, natural variations in fish condition likely confound interpretation of most indicators of yellow perch health.…”

“…Two of them (Eastwood and Couture 2002;Kraemer et al 2006b) examined seasonal variations in four or five lakes within a single region, and only examined the condition factor as an indicator of yellow perch health. The third (Audet and Couture 2003) focused on only two lakes from the Sudbury area but also examined variations in metabolic capacities. These combined studies indicate that both tissue metal concentrations and condition vary seasonally in yellow perch.…”

“…Several studies have reported that yellow perch tissue metal concentrations vary seasonally, in contaminated lakes (Eastwood and Couture 2002;Audet and Couture 2003;Kraemer et al 2006b) but also sometimes in clean lakes (data examined later from Couture et al 2008a). Here we provide evidence with implications for ERA of how ignoring these seasonal variations could falsely lead to conclusions that fish from contaminated lakes do not differ in tissue metal concentrations compared to clean fish.…”