COMPARATIVE NUTRITIVE VALUE OF AN INVASIVE EXOTIC PLANT SPECIES, Prosopis glandulosa TORR. var. glandulosa, AND FIVE INDIGENOUS PLANT SPECIES COMMONLY BROWSED BY SMALL STOCK IN THE BORAVAST AREA, SOUTH-WESTERN BOTSWANA

Abstract

Nutritive value of an invasive exotic plant species, Prosopis glandulosa Torr. var. glandulosa, and five indigenous plant species commonly browsed by livestock in Bokspits, Rapplespan, Vaalhoek and Struizendam (BORAVAST), southwest Botswana, was determined and compared. These five indigenous plant species were Vachellia hebeclada (DC.) Kyal. & Boatwr. subsp. hebeclada, Vachellia erioloba (E. Mey.) P.J.H. Hurter, Senegalia mellifera (Vahl) Seigler & Ebinger subsp. detinens (Burch.) Kyal. & Boatwr., Boscia albitrunca (Burch.) Gilg & Gilg-Ben. var. albitrunca and Rhigozum trichotomum Burch. The levels of Crude Protein (CP), Phosphorus (P), Calcium (C), Magnesium (Mg), Sodium (Na) and Potassium (K) were determined for the plants foliage and pods (where available). All plant species had a CP value higher than the recommended daily intake. There are however multiple mineral deficiencies in the plant species analysed. Nutritive value of Prosopis glandulosa is comparable to those other species despite the perception that livestock that browse on it are more productive than those that browse on the other plant species.