Temperature effects on the feeding and electron transport system (ETS) activity of Gammarus fossarum

Abstract

The effects of an increase in water temperature as a direct consequence of global change on organisms living in springs and spring brooks have rarely been studied in laboratory experiments. In this study, experiments were conducted to test the response of Gammarus fossarum Koch, 1836, as an abundant representative of the European spring fauna, to changing water temperatures. The aim was to find out experimentally how G. fossarum reacts to varying and increasing water temperatures. The experiments were conducted in flow channels with spring water. In each flow channel, G. fossarum were placed in boxes with a flow-through system for 4 weeks. Two analytical methods were applied: the feeding activity of the amphipods was quantified in order to determine the reaction of G. fossarum on the level of the organism and the respiratory electron transport system (ETS) assay was conducted in order to determine changes in the test organisms on the cellular level. The results show that the feeding activity of G. fossarum increased with increasing water temperature, up to an optimum, indicating an increase in their metabolic activity. The ETS activity does not show significant differences at the different temperatures tested. A possible explanation for this is the ability of the organisms to adapt quickly to the changed environmental circumstances.

Can multi-generational exposure to ocean warming and acidification lead to the adaptation of life-history and physiology in a marine metazoan?

“…ETS activity, a proxy for maximum mitochondrial capacity (Schmidlin et al, 2015), also increased in the ocean warming scenario and, interestingly, this is the only trait in which changes persisted across both F5 and F6 following transplantation. Closer examination of the responses reveals a change in the direction of the reaction norm between the F5 and F6.…”

“…CS and ETS were chosen for their function: CS is a proxy for mitochondrial density (Rabøl et al, 2006), while ETS is a marker of maximum mitochondrial capacity (Schmidlin et al, 2015). We focused on mitochondria because it is likely that the mitochondrial response across multiple generations determines the magnitude of temperature change that a species can withstand (Blier et al, 2014;Seebacher et al, 2010;Tomanek, 2015).…”

Additive effects of temperature and infection with an acanthocephalan parasite on the shredding activity of Gammarus fossarum (Crustacea: Amphipoda): the importance of aggregative behavior

“…An increase in temperature is known to increase metabolic rate in ectothermic species (Brown et al ., ), thus leading to higher energy requirements. Accordingly, and as observed in previous studies (Coulaud et al ., ; Pellan et al ., ; Schmidlin et al ., ), leaf consumption increased between low and medium temperatures in the present study. However, at the highest temperature, food consumption dramatically decreased in most single individuals.…”

Can trans‐generational experiments be used to enhance species resilience to ocean warming and acidification?

“…) and a relative measurement of aerobic metabolism, as well as the activity of the Electron Transport System (ETS), an enzyme complex located on the inner mitochondrial membrane widely accepted as a marker for maximum mitochondrial capacity (Schmidlin et al. ). Additionally, a by‐product of aerobic metabolism, ROS were measured in adult females (Rivera‐Ingraham et al.…”

“…; Schmidlin et al. ) were also measured in offspring to provide a mechanistic underpinning to any observed differences in life‐history responses (Sibly and Calow ).…”