CHEMICAL COMPOSITION, MINERAL CONTENT, IN VITRO GAS PRODUCTION AND RELATIVE FEED VALUE OF STEVIA REBAUDIANA BERTONI

MILENA TZANOVA, DIMITAR PAVLOV, JIVKO KRASTANOV, DIMAN DIMANOV, NELI GROZEVA, MARIYA GERDZHIKOVA, SVETOSLAVA TERZIEVA

Abstract: The aim of present study was to determine the chemical composition, digestibility, gas production, energy nutrition, relative feed value, and the use of S. rebaudiana as a forage crop. The chemical composition and mineral content of biomass from Stevia rebaudiana Bertoni were determined. The average crude protein content in the biomass was 86.33 g/kg of dry matter (DM); crude fat – 11.79 g/kg DM; crude fibre – 284.68 g/kg DM; ash – 96.56 g/kg DM and nitrogen free extracts (NFE) – 520.64 g/kg DM. The mineral content in the biomass of S. rebaudiana was similar to that of meadow grasses. Structural fibre components were on average for neutral detergent fibre (NDF) 35.52% and acid detergent fibre (ADF) 31.18% which are close to that of alfalfa and legume grasses. New data were obtained concerning in vitro gas production of S. rebaudiana biomass at 24 hour period – it was 225.83 dm/ml average, and at 48 hour period – 246.70 dm/ml (CO2 and CH4), which is close to the group of legume and cereal meadow grasses. The relative feed value (RFV) of S. rebaudiana biomass is close to that of perennial legumes. Regression equations were developed for advanced determination of: the quantity of metabolizable energy (ME), through the gas production at 24 hour period; and the relative feed value (RFV) and acid detergent fibre through the neutral detergent fibre.

Keywords: chemical composition; detergent fibre; in vitro gas production; mineral content; relative feed value; Stevia rebaudiana

Date published: 2018-04-03