Comparative bilateral asymmetry of six Barbus species collected from the rivers in western Anatolia, Republic of Türkiye

ABSTRACT

The bilateral asymmetry was analysed on 259 fish specimens comprising six Barbus species collected in June-August 2010 from rivers in western Anatolia. The goals of this study are: (1) to check for the levels of bilateral asymmetry amid the ten morphological features of the six Barbus species and (2) to compare the levels of this asymmetry among the ten localities in western Anatolia. The possibility of applied investigations using bilateral asymmetry and fishes as an indicator of the health of the freshwater systems was also conducted. Statistical analyses have shown that the ten morphological traits chosen for this study exhibit variable levels of bilateral asymmetry in the six Barbus species collected from the ten localities studied. The asymmetry value was highest for snout length and lowest for the prepectoral fin length observed in B. pergamonensis. An increasing tendency in asymmetry levels was exhibited for each of the ten morphological traits in the fish length groups selected for each Barbus species assessed. The result of the individuals being right-handed or left-handed has shown that specific morphological characteristics are either dextral or sinistral or showed no bilateral asymmetry in different Barbus species studied.

KEYWORDS:

• Actinopterygii
• Barbus species
• ecological factors
• Cyprinidae
• Türkiye
• environment

Acknowledgements

LAJ developed the research idea and wrote manuscripts with input from all authors; SSG and ZG set up the study; literature review LAJ and SSG; experiments SSG, ZG, and FK; data collection SSG, FK; statistics JMP; supervision LAJ and SSG. The care of experimental animals was consistent with the Republic of Türkiye’s animal welfare laws, guidelines, and policies approved by the Rize University Local Ethics Committee for Animal Experiments (Permit reference number 2011/04). Fishes were collected for faunal surveys preserved in 5% formaldehyde or 96% ethanol and stored in 70% ethanol after anaesthesia using tricaine methanesulfonate. Surgical procedures were only performed for the excision of fin clips. The experimental conditions did not distress any fish involved in our experiments.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The article’s data will be shared by the corresponding author upon reasonable request.

Additional information

Funding

This study was supported by a grant from the Süleyman Demirel University Scientific Research Projects Coordination Unit (Project No: SDÜ-BAP1987D09).