Dietary vitamin E enhances growth performance, gonadal maturation, and dmrt1/foxl2 expression in climbing perch (Anabas testudineus)

Vitamin E contributes to reproductive success in fish by preserving cellular membrane stability and supporting gonadal tissue function. This ten-month study, conducted using a cage culture system in an earthen pond, evaluated the impact of a vitamin E-supplemented diet on gonadal maturation in the indigenous climbing perch ( Anabas testudineus ). Thirty fish per cage were reared in six cages, and the fish were fed diets with different amounts of vitamin E (0, 50, 100, 150, 200, and 250 mg/kg feed, designated as T 0 to T 5 ). The initial average length and weight of male and female Anabas testudineus were 12.34 ± 0.36 cm and 52.00 ± 0.62 g, and 12.97 ± 0.21 cm and 52.98 ± 0.43 g, respectively. In addition to histological and gene expression analyses, weekly measurements of fish weight, length, and water quality parameters were performed. T 2 (100 mg/kg vitamin E) showed the greatest growth in weight (69.68 ± 8.35 g) and length (17.035 ± 2.366 cm), with significant differences from other treatments (p < 0.05). Histological analyses revealed that T 2 showed the most concentrated spermatozoa in males and the largest, clearest mature oocytes in females. Moreover, qPCR analysis showed significant upregulation of dmrt1 in male and foxl2 in female A. testudineus under the T 2 treatment (100 mg vitamin E/kg) (p < 0.05). These results demonstrate that dietary Vitamin E supplementation modulates key reproductive genes, thereby enhancing gonadal maturation. Throughout the study, water quality parameters remained within acceptable limits. Overall, treatment T 2 showed the best performance, indicating that 100 mg/kg feed is the optimal level for improving growth, gonadal health, and reproductive performance in A. testudineus . This study provides a basis for optimizing vitamin E supplementation in reproductive management strategies to support the long-term production of A. testudineus . • Diets with 0–250 mg/kg vitamin E tested growth, gonadal development, and gene expression in Anabas testudineus • Optimal growth and gonadal maturation occurred in fish fed diet supplemented with 100 mg/kg vitamin E. • Fish fed 100 mg/kg vitamin E showed mature oocytes and concentrated spermatozoa in gonadal histology. • qPCR revealed significant upregulation of dmrt1 (males) and foxl2 (females) in the 100 mg/kg (p < 0.05). • Results support 100 mg/kg vitamin E boosts reproductive gene expression and gonadal health in Anabas testudineus .