Morphological and morphometric features of the abnormal and normal saccular otoliths in flatfishes
Özet
The fish's inner ear consists of three interconnected semicircular canals and
otolith organs located in these canals, which are responsible for balance and
hearing. Abnormalities in these organs can affect the vital activities of the fish.
The main purpose of this study was to determine the morphological and morphometric characteristics of abnormal and normal sagittal otoliths in the four
flatfish species (Lepidorhombus boscii, Platichthys flesus, Solea solea, and
Pegusa lascaris) sampled from three seas (Aegean Sea, Mediterranean Sea, and
Black Sea). Abnormalities in otoliths are investigated using light microscopy,
scanning electron microscopy, and Raman spectroscopy. The otolith morphometric measurements and morphology are recorded for abnormal and normal
otoliths for each species. It was determined that the four flatfish species examined in the present study showed differences in the morphological features of
normal and abnormal otoliths in the blind and eyed sides. In addition, statistical differences were observed when the weight, length, width, perimeter, and
area values of normal and abnormal otoliths of all species were compared
(p < .05). The four types of saccular otoliths were defined, one normal (type 0)
and three abnormal (type 1, type 2, and type 4) for four flatfish species. The
current study presents for the first-time abnormal otolith morphology information on blind and eyed side sagittal otoliths in these flatfish species. Abnormalities in the anatomical structures of bony parts such as otoliths in fish may be
caused by pollution, nutritional problems, stress, and environmental factors as
well as a combination of these.
