University of Guilan Caspian Journal of Environmental Sciences 1735-3033 20 4 2022 10 01 Feeding indices of Planiliza abu (Heckel, 1843) in Karun River, Southwestern Iran 693 700 5721 10.22124/cjes.2022.5721 EN Miaad Jorfipour Department of Natural Resources, Isfahan University of Technology, Isfahan, Iran Yazdan Keivany Department of Natural Resources, Isfahan University of Technology, Isfahan, Iran Fatemeh Paykan-Heyrati Department of Natural Resources, Isfahan University of Technology, Isfahan, Iran Zaniar Ghafoori Department of Fisheries, Faculty of Natural Resources, University of Tehran, Karaj Campus, Iran Journal Article 2022 08 01 The feeding characteristics of <em>Planiliza abu </em>in Karun River, Khuzestan Province,<strong> </strong>southwestern Iran were studied by collecting 460 specimens from November 2016 to September 2017. The specimens were anesthetized in 1% clove oil, fixed in 10% buffered formalin and transferred to the laboratory. The average length and weight of all specimens were 13.18 ± 1.35 cm and 31.05 ± 9.22 g, respectively. The average condition factor for both males and female was 1.34, exhibiting no significant differences in different months in both sexes (p > 0.05). The mean relative length of gut in all fish was 2.27 ± 0.36 during the year.  The highest gastrosomatic index (GSI) value was in September (12.07), while the lowest in February and March displaying significant differences in different months (p < 0.05). A total of 214 empty stomachs were found amongst the 460 fish samples and there were no significant differences in the ratio of empty stomachs in different months (p > 0.05). Therefore, based on the visual observations, RLG and GSI, it could be concluded that this species is an omnivorous fish (mainly aquatic insects and plants, algae, diatoms, and detritus) with a modest feeding throughout the year. https://cjes.guilan.ac.ir/article_5721_00e8c09edc4696bfcd75b61f6b1da069.pdf