The leaves and young shoots of Salvadora persica are browsed by all stock, but saltbush tends to be valued more as a camel, sheep and goat forage since cattle are rarely present in the driest parts of its distribution range (Orwa et al., 2009). The pods are also eaten by camels, sheep, goats and cattle as a protein supplement (Gezahegn, 2006). Camels are tall enough to be able to browse the upper parts of the Salvadora persica tree and their prehensile upper lip is used for selectively grasping plant parts (Faye et al., 1989; Kuria et al., 2005; Shamat et al., 2010; Wilson, 1989). They can trap a branch or shoot tightly in the mouth and with their heads turned sideways strip leaves off the branch (Kassilly, 2002).
Saltbush is particularly important in some countries during the dry season, when it may be the only forage available (Shamat et al., 2010). In Kenya, for instance, it is a very important forage for camels in desert areas of the country (Stiles et al., 1991) and one of the preferred trees or tall bushes eaten by camels, with Euphorbia spp, Maerua angolensis and Balanites aegyptiaca (Faye et al., 1989; Kassilly et al., 2000). In Senegal, saltbush can be a valuable supplement for zebu cows fed rice straw during the dry season (Molénat et al., 2005). In this country, leaves and young twigs are eaten by cattle, sheep, goats and camels (Diallo, 1973).
The leaves of Salvadora persica have a high water content (15-36%) and constitute a precious water source for animals such as camels, with a very high water recycling capacity (Faye et al., 1989; Kuria et al., 2005). The leaves contain about 11-13% CP in the DM, which is sufficient to meet the nutritional requirements of camels (Al-Dosari, 2001; Rangnekar, 1992). Leaves of saltbush have a quite good nutritive value relative to competing species. For instance, their in vitro dry matter digestibility is higher than that of Avicennia marina (76.6% vs. 60.5%) (Al-Dosari, 2001). A very high in vitro digestibility (98%) has also been reported (Shaltout et al., 2008). Indeed, leaves are considered as the best forage for fattening camels or for camel cows when delivering calves (Gezahegn, 2006). The leaves are also said to increase lactation in cows (Orwa et al., 2009). However, the composition of saltbush depends on the growth stage, season and soil, and on the parts selected by the animals, so the nutritive value of the plant consumed is highly variable.
The leaves contain very high levels of minerals (up to 40%), which is a problem for almost all ruminants, excepted for camels that are able to cope with it by their ability to store minerals when fed in excess (Shaltout et al., 2008). Salvadora persica bushes are low in Cu, Zn, Mn, contain suitable amounts of iron, but excessive amounts of Mn, Se and S (Assaeed et al., 1995; Faye et al., 1990). Its richness in NaCl, which gives it its surname "saltbush", constitutes a true "salt cure" for livestock (Schareika, 2002). The high salt content of the leaves is said to affect the taste of milk (Orwa et al., 2009).
