Effects of ethoxyquin on growth performance,body composition,intestinal antioxidant capacity,and inflammatory response of loach

SONG Zhicheng; ZOU Xi; LI Lu; CHEN Xiangning; XU Jianhe; CHENG Hanliang; SHAO Mingxu; WEI Chaoqing

doi:10.13557/j.cnki.issn1002-2813.2025.02.014

Abstract：The aim of this study was to investigate the effects of ethoxyquinoline(EQ)on the growth performance,body composition,intestinal antioxidant capacity,and inflammatory response of loach.A total of 1 800 loaches with an initial weight of(4.94±0.05)g were randomly divided into four groups,with three replicates per group and 150 loaches per replicate.The loaches were fed iso-nitrogen and iso-lipid diets supplemented with 0(EQ0 group),50(EQ50 group),150(EQ150 group)and 450 mg/kg EQ(EQ450 group),respectively.The experiment lasted for 56 days.The results showed that compared with the control group,the weight gain rate and specific growth rate in EQ50 and EQ150 groups were significantly increased(P＜0.05),while those in EQ450 group were significantly decreased(P＜0.05).There were no significant differences in whole body composition content among all groups(P＞0.05).The intestinal catalase(CAT)activity of EQ50 and EQ150 groups was significantly higher than that of EQ0 group(P＜0.05),the malondialdehyde(MDA)content was significantly lower than that of EQ0 group(P＜0.05),the intestinal superoxide dismutase(SOD),CAT and T-AOC activities of EQ450 group were significantly higher than that of other groups(P＜0.05).Compared with EQ0 group,the intestinal nuclear factor E2-related factor 2(NRF2),SOD,CAT and glutathione peroxidase(GSH-Px)genes expressions in all EQ groups were significantly increased(P＜0.05),while the Kelch-like ECH associated protein 1(KEAP1)expression was significantly decreased(P＜0.05).Compared with EQ0 group,intestinal villus height and epithelial cell height in EQ50 and EQ150 groups were significantly increased(P＜0.05).The expressions of intestinal interleukin-1β(IL-1β),interleukin-8(IL-8)and tumor necrosis factor-α(TNF-α)genes in EQ50 group were significantly decreased(P＜0.05),while those in EQ450 group were significantly increased(P＜0.05).The study indicates that 150 mg/kg EQ supplementation is recommended for loach feed based on growth performance,intestinal antioxidant capacity,and inflammatory response.