Effects of dietary steviol glycosides on the growth, feed intake and intestinal short-chain fatty acids in red hybrid tilapia

Abstract

Aim: Stevia is a natural sweetener but is not readily metabolized or fermentable in animals. It may have potential as a feed attractant; however, there is limited information on the effects of dietary Stevia in fish. Methodology: A 76-day-study was performed to assess the growth, feed intake, body indices, muscle proximate composition and intestinal short chain fatty acids (SCFA) in red hybrid tilapia fed with increasing Stevia (steviol glycosides) at 0, 1, 3 and 6%. A second experiment was performed to determine any changes in plasma glucose, cholesterol or triglyceride levels in red hybrid tilapia at 1, 3, 6, 12 and 24 hr after being fed 0 or 6% Stevia. Results: In experiment 1, dietary Stevia had no significant effect (p > 0.05) on any of the measured parameters in tilapia and in experiment 2, dietary Stevia had no significant effect (p > 0.05) on the tested plasma biochemistry. Interpretation: These findings indicate that Stevia did not improve diet palatability to tilapia, as well as not being metabolized for energy or fermented. Based on these findings, there is no advantage to including Stevia at the tested levels in the diets of tilapia.