Effect of Humic Substances as Feed Additive on the Growth Performance, Antioxidant Status, and Health Condition of African Catfish (Clarias gariepinus, Burchell 1822)
Abstract
Global aquaculture requires the development of new strategies to maintain the continuous growth of production, such as the development of aquafeeds with sustainable and functional components, ensuring better growth and health conditions of fish. Humic substances (HS) have the potential to become a functional additive for aquafeeds, as their growth-promoting and immunostimulant effects have been found in farm animals.
Recently, there is limited knowledge on how different HS affects overall performance of various fish species. Therefore, in this study, the effects of four experimental Siberian leonardite HS diets (HS0, HS1, HS3, and HS6) on growth and production parameters, condition and somatic indices, overall mortality, health condition, and antioxidant status were assessed in juvenile Clarias gariepinus, which is well-known as a fast-growing and high-resistant fish species when reared at high stocking densities up to 500 kg m-3.
In this study, growth and production parameters, condition, and somatic indices or mortality rate were not significantly affected by tested HS diets. On the other hand, moderately positive effects were observed regarding health status and good antioxidant parameters, especially in the HS3 group over the 56-day study.