Relationships between farmer perceptions and temporal variation in nutritive value of browse species on savanna rangelands

Abstract

In livestock-based livelihoods of the developing world, determination of the nutritive value of browse species is mainly associated with farmer perceptions. Additionally, little is known on seasonal variation in nutritive value of these species in some areas. Therefore, chemical analysis is necessary to validate farmer nutritive value ranking, because this has implications on rangeland management. We compared farmer perceptions with chemically quantified crude protein, dry matter, acid detergent fibre (ADF), and dry organic matter digestibility (DOMD) of seven browse species. Crude protein and DOMD were higher in the wet season compared to the dry season. However, ADF was higher in the dry season. There was a strong negative correlation between acid detergent fibre and DOMD during the wet season (r = −0.631, p < 0.05). Positive, though non-significant correlations were observed between farmer perceptions of ‘most nutritious according to herder’ and CP (r = 0.29, p = 0.54), farmer perception of ‘most abundant species’ and DM (r = 0.13, p = 0.78), and between farmer perception of ‘highly preferred species by livestock’ and DOMD (r = 0.32, p = 0.48). Therefore, although farmer perceptions of nutritive value of browse species are important in strategic utilisation of rangelands, they should not replace chemical analysis, but should complement each other.

Keywords: chemical composition, sustainable agriculture, veld