| Registro completo |
| Provedor de dados: |
5
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| País: |
France
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| Título: |
Physiological determinants of individual variation in sensitivity to an organophosphate pesticide in Nile tilapia Oreochromis niloticus
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| Autores: |
Mckenzie, David
Blasco, Felipe R.
Belao, Thiago C.
Killen, Shaun S.
Martins, Nathan D.
Taylor, Edwin W.
Tadeu Rantin, F.
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| Data: |
2017-08
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| Ano: |
2017
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| Palavras-chave: |
Trichlorfon
Critical swimming speed
Metabolic rate
Respirometry
Nile tilapia
Individual variation
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| Resumo: |
Individual variation in sub-lethal sensitivity to the organophosphate pesticide trichlorfon was investigated in Nile tilapia, using critical swimming speed (U-crit) as an indicator. Tilapia exposed for 96 h to 500 mu g l-1 trichlorfon at 26 degrees C (Tcfn group, n = 27) showed a significant decline in mean U-crit, compared to their own control (pre-exposure) performance in clean water (-14.5 +/- 2.3%, mean +/- SEM), but also compared to a Sham group (n = 10) maintained for 96 h in clean water. Individuals varied in their relative sensitivity to the pesticide, with the decline in U-crit after exposure varying from 1 to 41%. The U-crit of the Tcfn group did not recover completely after 96 h in clean water, remaining 9.4 +/- 3.2% below their own control performance. The decline in performance was associated with a significant increase in net cost of aerobic swimming, of +28.4 +/- 6.5% at a sustained speed of 2 bodylengths s(-1), which translated into a significant decline in swimming efficiency (E-swim) of -17.6 +/- 4.0% at that speed. Within the T-cfn group, individual E-swim was a strong positive determinant of individual U-crit across all trials, and a strong negative determinant of individual% decline in U-crit after pesticide exposure (P < 0.001, linear mixed effect models). Trichlorfon had no effects on standard metabolic rate or active metabolic rate (AMR) but, nonetheless, individual U-crit in all trials, and% decline in U-crit after exposure, were strongly associated with individual AMR (positively and negatively, respectively, P < 0.001). Individual U-crit under control conditions was also a strong positive determinant of Ucrit after trichlorfon exposure (P < 0.001), but not of the% decline in U-crit performance. In conclusion, the OP pesticide impaired U-crit performance by reducing E-swim but individual tilapia varied widely in their relative sensitivity. Intrinsic individual physiology determined effects of the pesticide on performance and, in particular, good swimmers remained better swimmers after exposure.
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| Tipo: |
Text
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| Idioma: |
Inglês
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| Identificador: |
https://archimer.ifremer.fr/doc/00625/73705/74889.pdf
DOI:10.1016/j.aquatox.2017.06.001
https://archimer.ifremer.fr/doc/00625/73705/
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| Editor: |
Elsevier Science Bv
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| Formato: |
application/pdf
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| Fonte: |
Aquatic Toxicology (0166-445X) (Elsevier Science Bv), 2017-08 , Vol. 189 , P. 108-114
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| Direitos: |
info:eu-repo/semantics/openAccess
restricted use
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