TY - JOUR
T1 - Acclimation to Cu in fathead minnows
T2 - Does age influence the response?
AU - Sellin, Marlo K.
AU - Tate-Boldt, Erik
AU - Kolok, Alan S.
N1 - Funding Information:
This study was partially supported by the University of Nebraska at Omaha (UNO) Department of Biology, the UNO Graduate College and by the Nebraska Water Center. Additional support was given by NIH National Institute of Environmental Health Science, Grant #1 R15 ES11788-01 and by NIH Grant #1 P20 RR16469 from the BRIN Program of the National Center for Research Resources. Its contents are solely the responsibility of the authors and do not necessarily represent the views of any of the funding agencies.
PY - 2005/8/30
Y1 - 2005/8/30
N2 - This study had two primary objectives. The first was to determine if the length of exposure necessary for acclimation to Cu to develop in larval fathead minnows (Pimephales promelas) is different than that for juveniles. The second objective was to determine whether the acclimatory response, as determined by organism survival, is consistent with acclimation as determined by whole-body Na+. Six experiments were conducted: four using larval (<20-d-old) and two using juvenile (<60-d-old) fathead minnows. Within each experiment, fish were allocated to one of four groups: unexposed, continuously exposed, episodically exposed or naïvely exposed. The continuous group was exposed to a sublethal Cu exposure (125 μg/L) for 8, 12, 16 or 20 d and then subjected to a survival test at a lethal dose (375 μg/L). Fish in the episodic group were exposed to the sublethal dose for either 4 or 8 d, given a depuration period of varying lengths (4-16 d) then subjected to a survival test. Naïve minnows were maintained in clean water then given the survival challenge. Results from survival tests show that the larvae acclimate after only a 4-d sublethal exposure to Cu. In contrast, juveniles require a 16-d exposure to acclimate. Once acclimation had developed, there was a strong relationship between larval survival and whole-body Na+. Acclimated larvae maintained whole-body Na+ relative to unexposed fish, while unacclimated larvae did not. Interestingly, this was not the case for juveniles, as acclimated and unacclimated groups did not differ with respect to whole-body Na+ concentrations. The results of this study show that age influences the time course and possibly the mechanisms of acclimation in fathead minnows exposed to Cu.
AB - This study had two primary objectives. The first was to determine if the length of exposure necessary for acclimation to Cu to develop in larval fathead minnows (Pimephales promelas) is different than that for juveniles. The second objective was to determine whether the acclimatory response, as determined by organism survival, is consistent with acclimation as determined by whole-body Na+. Six experiments were conducted: four using larval (<20-d-old) and two using juvenile (<60-d-old) fathead minnows. Within each experiment, fish were allocated to one of four groups: unexposed, continuously exposed, episodically exposed or naïvely exposed. The continuous group was exposed to a sublethal Cu exposure (125 μg/L) for 8, 12, 16 or 20 d and then subjected to a survival test at a lethal dose (375 μg/L). Fish in the episodic group were exposed to the sublethal dose for either 4 or 8 d, given a depuration period of varying lengths (4-16 d) then subjected to a survival test. Naïve minnows were maintained in clean water then given the survival challenge. Results from survival tests show that the larvae acclimate after only a 4-d sublethal exposure to Cu. In contrast, juveniles require a 16-d exposure to acclimate. Once acclimation had developed, there was a strong relationship between larval survival and whole-body Na+. Acclimated larvae maintained whole-body Na+ relative to unexposed fish, while unacclimated larvae did not. Interestingly, this was not the case for juveniles, as acclimated and unacclimated groups did not differ with respect to whole-body Na+ concentrations. The results of this study show that age influences the time course and possibly the mechanisms of acclimation in fathead minnows exposed to Cu.
KW - Acclimation
KW - Copper
KW - Fathead minnow
KW - Organism age
KW - Whole-body sodium
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U2 - 10.1016/j.aquatox.2005.05.005
DO - 10.1016/j.aquatox.2005.05.005
M3 - Article
C2 - 15955579
AN - SCOPUS:23044500752
VL - 74
SP - 97
EP - 109
JO - Aquatic Toxicology
JF - Aquatic Toxicology
SN - 0166-445X
IS - 2
ER -