Thorns
The presence of thorns in Acacia karroo can be a problem for the ingestion of leaves by livestock, which may be alleviated by cutting and sieving it to produce a leaf meal (Mapiye et al., 2011).
Tannins
Acacia karroo contains high levels of condensed tannins, with values between 5.5% and 10% DM (Brown et al., 2016; Mapiye et al., 2011; Mokoboki et al., 2005; Dube et al., 2001), when a 2-8% range is expected to be beneficial to ruminants (Mueller-Harvey, 2006); Mapiye et al., 2011). Condensed tannins of Acacia karroo have been reported to increasing fecal N excretion and decrease N retention in goats, which should be the result of the complexation between tannins and endogenous proteins (Mapiye et al., 2011). The condensed tannins contents of Acacia karroo is expected to be higher in old plants, during the dry season, on low quality soils (Scogings et al., 2008).