<abstract xmlns="http://www.w3.org/1999/xhtml"><p>The relationship between pollution levels in river sediment and fluctuating asymmetry of resident silurid fish species, <italic>Silurus triostegus</italic> Heckel, was assessed. Eight bilateral body proportions were analyzed in 1,500 fish from eight river locations. Sediment pollution was measured based on the analysis of heavy metals (Cd, Cr, Cu, Ni, Pb and Zn) and organochlorine pesticides (DDT, DDD, DDE, chlordane, dieldrin, and lindane). The mean quotient approach (mERMq) was used to characterize sediment toxicity, which ranged from low to moderate levels for heavy metals and from low to severe for organochlorides. Variation was noted in the measurements of fish body morphometrics among the sampling locations, which suggested responses to local environments. Levels of asymmetry were positively correlated with both organochlorine pesticides and heavy metals across locations. These results suggest that fish asymmetry variations could be useful for estimating stress caused by organic toxicity based on the mERMq approach.</p></abstract>

The relationship between pollution levels in river sediment and fluctuating asymmetry of resident silurid fish species, Silurus triostegus Heckel, was assessed. Eight bilateral body proportions were analyzed in 1,500 fish from eight river locations. Sediment pollution was measured based on the analysis of heavy metals (Cd, Cr, Cu, Ni, Pb and Zn) and organochlorine pesticides (DDT, DDD, DDE, chlordane, dieldrin, and lindane). The mean quotient approach (mERMq) was used to characterize sediment toxicity, which ranged from low to moderate levels for heavy metals and from low to severe for organochlorides. Variation was noted in the measurements of fish body morphometrics among the sampling locations, which suggested responses to local environments. Levels of asymmetry were positively correlated with both organochlorine pesticides and heavy metals across locations. These results suggest that fish asymmetry variations could be useful for estimating stress caused by organic toxicity based on the mERMq approach.

Directional fluctuating asymmetry in certain morphological characters as a pollution indicator: Tigris catfish (<italic>Silurus triostegus</italic>) collected from the Euphrates, Tigris, and Shatt al-Arab Rivers in Iraq

Faculty of Agriculture, Department of Animal Science

Fisheries & Aquatic Life

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Directional fluctuating asymmetry in certain morphological characters as a pollution indicator: Tigris catfish () collected from the Euphrates, Tigris, and Shatt al-Arab Rivers in Iraq

The relationship between pollution levels in river sediment and fluctuating asymmetry of resident silurid fish species, Silurus triostegus Heckel, was...

Directional fluctuating asymmetry in certain morphological characters as a pollution indicator: Tigris catfish (Silurus triostegus) collected from the Euphrates, Tigris, and Shatt al-Arab Rivers in Iraq

Published Online: May 11, 2020

Page range: 18 - 32

Received: Aug 19, 2019

Accepted: Feb 28, 2020

DOI: https://doi.org/10.2478/aopf-2020-0003

Keywords
Siluridae, morphology, morphometric characters, Iraq, pollution, bilateral asymmetry

© 2020 Laith A. Jawad et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Directional fluctuating asymmetry in certain morphological characters as a pollution indicator: Tigris catfish (Silurus triostegus) collected from the Euphrates, Tigris, and Shatt al-Arab Rivers in Iraq

Published Online: May 11, 2020

Page range: 18 - 32

Received: Aug 19, 2019

Accepted: Feb 28, 2020

DOI: https://doi.org/10.2478/aopf-2020-0003

KeywordsSiluridae, morphology, morphometric characters, Iraq, pollution, bilateral asymmetry

© 2020 Laith A. Jawad et al., published by Sciendo

This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 3.0 License.

Keywords
Siluridae, morphology, morphometric characters, Iraq, pollution, bilateral asymmetry