Confinement during field studies may jeopardize antioxidant and physiological responses of Nile tilapia to contaminants.
This work evaluates the effects of caging, a known confinement stress, in Nile tilapia (Oreochromis niloticus) during an environmental study in Cubatão river, southern Brazil. Caging animals for 7 days, regardless of being at the reference or at a contaminated site, resulted in lower levels of antioxidant-related defenses (glutathione, glutathione S-transferase, glucose-6-phosphate dehydrogenase) in liver and physiological parameters (blood glucose and lactate) as compared with free-swimming animals. Higher hepatic glutathione reductase activity and elevated Hb content could be associated to contaminant exposure. In conclusion, the confinement stress in caged Nile tilapia biochemical and physiological disturbances, acting as a confounding factor in field studies.
Biochemistry Department, Federal University of Santa Catarina, 88040-900 Florianópolis, SC, Brazil. Electronic address: rafael.trevisan@gmail.com.
Rafael
R
Trevisan
Marcela
M
Uliano-Silva
Jeferson Luis
JL
Franco
Thais
T
Posser
Roberto
R
Hoppe
Marcelo
M
Farina
Afonso Celso Dias
AC
Bainy
Alcir Luiz
AL
Dafre
D000818:Animals; D001774:Blood Chemical Analysis; D023681:Cichlids / Q000378:metabolism / Q000502:physiology*; D020378:Confined Spaces; D004798:Enzymes / Q000378:metabolism; D005978:Glutathione / Q000032:analysis / Q000097:blood; D008099:Liver / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D013312:Stress, Physiological; D013438:Sulfhydryl Compounds / Q000097:blood; D014874:Water Pollutants, Chemical / Q000633:toxicity
D004798:Enzymes; D013438:Sulfhydryl Compounds; D014874:Water Pollutants, Chemical; D005978:Glutathione
Antioxidant; Biomarker; Confinement stress; Ecotoxicology; Fish; Oreochromis niloticus