Effect of supplemental selenium in fish feed boosts growth and gut enzyme activity in juvenile tilapia (Oreochromis niloticus)

Abstract

The investigations on the role of dietary micronutrient(s), such as selenium, has recently emerged as the fixate of researchers, notably in aquaculture. Our study aimed at investigation of the impact of dietary selenium on growth and digestive enzymes (DE) activity in juvenile tilapia. Three iso-nitrogenous diets with a sequential increase of selenium doses viz. 2 (T1), 4 (T2), and 8 (T3) mg/kg of fish feed, and selenium-deficient (T4) feed were dispensed in independent treatments. The juvenile fish growth and enzyme activities showed direct links to selenium dose. The T1 illustrated significantly higher (P < 0.05) accomplishments in average weight (21.28 ± 5.62 g), length (11.14 ± 1.041 cm), FRC (1.46 ± 0.23), and SGR (2.61 ± 0.07). The intestinal enzymes manifested selenium dose-linked activities with T1 as 2.41 ± 1.34 and 107.66 ± 2.54 of amylase and lipase, respectively. These enzymatic activities approximated with the fish body weight and length gains as well as growth indices (FCR, SGR) in T1. The linear projections further reinforced that selenium dose of 2 mg/kg (T1) is the most suitable dose for sustainable and profitable fish growth and enhanced activity of DE. In conclusion, selenium strongly impacted the juvenile growth, FCR, SGR and enzyme activity.