Examining the Effects of Chronic Selenium Exposure on Traditionally Used Stress Parameters in Juvenile American Alligators (Alligator mississippiensis)

Environmental contaminants, such as the trace element selenium (Se), are a continuing concern to species worldwide due to their potential pathophysiological effects, including their influence on the stress response mediated through glucocorticoids (GCs; stress hormones). Environmental concentrations of Se are increasing due to anthropogenic activities, including the incomplete combustion of coal and subsequent disposal of coal combustion wastes. However, most studies examining how Se affects GCs have been focused on lower trophic organisms. The objectives of this study were to investigate the effects of long-term Se exposure on traditionally used stress parameters and to identify which of these parameters best indicate Se accumulation in liver and kidney of the American alligator (Alligator mississippiensis), a top trophic carnivore found in the southeastern United States and known to inhabit Se-containing areas. Alligators were divided into three dietary treatments and fed prey spiked with 1000 or 2000 ppm of selenomethionine (SeMet) or deionized water (control treatment) for 7 weeks. Following the 7-week treatment protocol, blood and tissue samples were obtained to measure plasma corticosterone (CORT; the main crocodilian GC), tail scute CORT, the ratio of peripheral blood heterophils (H) to lymphocytes (L) as H/L ratio, and body condition. To evaluate which parameter best indicated Se accumulation in the liver and kidney, principal component and discriminant analyses were performed. The only parameter significantly correlated with liver and kidney Se concentrations was scute CORT. Our results suggest that measurement of CORT in tail scutes compared with plasma CORT, H/L ratios, and body condition is the best indicator of Se-exposure and accumulation in crocodilians.

Medienart:

E-Artikel

Erscheinungsjahr:

2019

Erschienen:

2019

Enthalten in:

Zur Gesamtaufnahme - volume:77

Enthalten in:

Archives of environmental contamination and toxicology - 77(2019), 1 vom: 01. Juli, Seite 14-21

Sprache:

Englisch

Beteiligte Personen:

Finger, John W [VerfasserIn]
Hamilton, Matthew T [VerfasserIn]
Kelley, Meghan D [VerfasserIn]
Stacy, Nicole I [VerfasserIn]
Glenn, Travis C [VerfasserIn]
Tuberville, Tracey D [VerfasserIn]

Links:

Volltext

Themen:

964MRK2PEL
Corticosterone
Environmental Pollutants
H6241UJ22B
Journal Article
Selenium
Selenomethionine
W980KJ009P

Anmerkungen:

Date Completed 08.08.2019

Date Revised 08.08.2019

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1007/s00244-019-00626-9

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM295978708