*3.1.1 Grazing resource*

The veld of the SEL is described as "*Aristida*-*Dactyloctenium*-*Eragrostis* other species grassveld". It has a carrying capacity of 0.084–0.14 tropical livestock units per hectare [6]. The grazing period ranges from November/December to April/ May. The veld remains nutritious and palatable for livestock across seasons. The herbaceous layer is dominated by *Aristida adscensionis* L., *Dactyloctenium giganteum* B.S. Fisher & Schweick., *Eragrostis viscosa* [Retz.] Trin., *Chloris virgata* Sw., and on deeper soils with more moisture, *Urochloa* spp., *Panicum* spp., *Cenchrus ciliaris* L., and *Digitaria* spp. [21]. On well-managed grazing systems, cattle exhibit annual live weight gains of 15 kg/ha. However, herbaceous species structure and composition are strongly influenced by seasonality of rainfall. For instance, the biomass disappears rapidly in drought years or when the start of the rainy season is delayed (**Figure 1**) [6]. Therefore, there is a need for supplementary feeding, especially during this period of scarcity of the grazing resource.

## *3.1.2 Crop residues*

In the SEL, poor-quality cereal crop residues (less than 4% crude protein) form the bulk of livestock supplementary feed in the dry season, which normally extends from May/June to October/November. The predominant crops are sorghum, millet, and maize. However, they are deficient in essential nutrients such as protein, phosphorus, calcium, and, to some extent, energy [22]. Such supplements have low feed intake resulting from low degradability and low digestibility. Therefore, they do not provide for optimum microbial growth in the rumen. As a result, animals raised on these low nutritive feeds exhibit poor condition and reduced reproductive performance [23]. Crop residues are managed in many ways

#### **Figure 1.**

*The grazing resource during dry seasons in the South East Lowveld of Zimbabwe.*

#### **Figure 2.**

*Maize stover forms part of the bulk of cereal stover supplements in the dry season.*

for livestock feeding. Cereal stovers are either grazed in situ or stored in stacks for supplementation during the dry season (**Figure 2**). During prolonged dry seasons, the first preference is for maintenance of productive animals such as lactating cows or the sick. Haulms from leguminous crops such as cowpea and groundnuts are also used in stall-feeding. Despite being of higher nutritive value than cereal stovers, they have limited availability as leguminous crops are not commonly cultivated at large scale. Recently, conservation agriculture has presented conflict of interest in utilisation of crop residues. Conservation agriculture is a farming method that utilises crop residues to retain moisture and enrich the soil [24]. Increased adoption of conservation agriculture creates limitations in the availability of crop residues for livestock feeding.

### *3.1.3 Browse trees*

Indigenous browse species are an important source of animal feed in livestockbased rural livelihoods of semi-arid areas (**Figure 3**) [25, 26]. The natural vegetation

**107**

**Table 1.**

*Adapted from Mudzengi et al. [36].*

*List of indigenous browse trees in the SEL.*

*Livestock Feeds and Feeding in Semi-Arid Areas of Southern Africa*

of the SEL is predominantly *Colophospermum mopane* [J.Kirk ex Benth.], J. Léonard woodlands found in association with *Kirkia acuminate* Oliv., *Dalbergia melanoxylon* Guill. & Perr, *Adansonia digitata* L., *Combretum* spp., *Acacia* spp., and *Commiphora*

[Harms] C.A.Sm. was discovered as a medicinal feed that helps livestock to survive drought [6]. Other browse species of the SEL are presented in **Table 1**. Most indigenous browse species remain abundant, evergreen, and relatively high in protein, metabolisable energy, vitamins, and minerals across seasons [27]. Unlike herbaceous species, browse species are less susceptible to climatic fluctuations, with crude protein (CP) levels of approximately 10% even in the dry season [28]. However, early and increased dependence on browse by livestock in semi-arid areas of the

spp. In addition, recently, a shrubby legume called *Neorautanenia brachypus*

**Scientific name Vernacular/English name** *Acacia albida* Shokoshoko/winter thorn *Acacia karroo* Muunga/sweet thorn

*Acacia xanthophloea* Kelenga/fever tree *Adansonia digitata* Mabuwu/baobab/muwu

*Aloe cameronii* Mhangani/aloe *Berchemia discolour* Munyii/bird plum *Boscia albitrunca* Shukutsu/shepherd's tree

*Brachystegia spiciformis* Musasa

*Julbernadia globiflora* Mutondo

*Neorautanenia brachypus* Zhombwe *Phragmites mauritianus* Shanga/reed grass

*Acacia tortilis* Sesani/umsasane/umbrella thorn

*Cassia abbreviata* Murumanyama/long-tail cassia *Cissus quadrangularis* Chiololo/chiololoti/muvengahonye *Colophospermum mopane* Mopane/xanatsi/turpentine tree *Combretum apiculatum* Chikukutsi/red bushwillow *Combretum imberbe* Mutsviri/mondo/monzo/leadwood *Dichrostachys cinerea* Mupangara/ndenge/sickle bush *Diospyros mespiliformis* Musuma/tithoma/jackalberry *Ficus sycomorus* Muonde/mikuwa/sycamore fig *Hippocratea crenata* Sengeti/valley paddle pod *Hyphaene petersiana* Makwangwala/Ilala/real fan palm

*Kigelia africana* Pfungu/mumvewa/sausage tree *Lonchocarpus capassa* Mupanda/umchitamuzi/rain tree *Mimusops zeyheri* Hlatsva/Chechete/red milkwood

*Salvadora persica* Dhungulu pokwe/mustard tree *Sclerocarya birrea* Mupfura/marula/mufura *Xanthocercis zambesiaca* Muhlaru/Musharo/Nyala berry

*DOI: http://dx.doi.org/10.5772/intechopen.90109*

*Livestock Feeds and Feeding in Semi-Arid Areas of Southern Africa DOI: http://dx.doi.org/10.5772/intechopen.90109*

*Livestock Health and Farming*

**Figure 1.**

**Figure 2.**

**106**

*3.1.3 Browse trees*

ity of crop residues for livestock feeding.

for livestock feeding. Cereal stovers are either grazed in situ or stored in stacks for supplementation during the dry season (**Figure 2**). During prolonged dry seasons, the first preference is for maintenance of productive animals such as lactating cows or the sick. Haulms from leguminous crops such as cowpea and groundnuts are also used in stall-feeding. Despite being of higher nutritive value than cereal stovers, they have limited availability as leguminous crops are not commonly cultivated at large scale. Recently, conservation agriculture has presented conflict of interest in utilisation of crop residues. Conservation agriculture is a farming method that utilises crop residues to retain moisture and enrich the soil [24]. Increased adoption of conservation agriculture creates limitations in the availabil-

*Maize stover forms part of the bulk of cereal stover supplements in the dry season.*

*The grazing resource during dry seasons in the South East Lowveld of Zimbabwe.*

Indigenous browse species are an important source of animal feed in livestockbased rural livelihoods of semi-arid areas (**Figure 3**) [25, 26]. The natural vegetation of the SEL is predominantly *Colophospermum mopane* [J.Kirk ex Benth.], J. Léonard woodlands found in association with *Kirkia acuminate* Oliv., *Dalbergia melanoxylon* Guill. & Perr, *Adansonia digitata* L., *Combretum* spp., *Acacia* spp., and *Commiphora* spp. In addition, recently, a shrubby legume called *Neorautanenia brachypus* [Harms] C.A.Sm. was discovered as a medicinal feed that helps livestock to survive drought [6]. Other browse species of the SEL are presented in **Table 1**. Most indigenous browse species remain abundant, evergreen, and relatively high in protein, metabolisable energy, vitamins, and minerals across seasons [27]. Unlike herbaceous species, browse species are less susceptible to climatic fluctuations, with crude protein (CP) levels of approximately 10% even in the dry season [28]. However, early and increased dependence on browse by livestock in semi-arid areas of the


#### **Table 1.**

*List of indigenous browse trees in the SEL.*

SEL during the dry season limits their availability in the rest of the season [29]. Fresh leaves of species such as *C. mopane*, for instance, are high in tannins and lignin [30, 31]. Additionally, indigenous browse species normally attract multiple uses at the livestock-wildlife interface with the more visible, more dominant, and more frequent browse species having more uses than less apparent plants [32]. They are used as sources of firewood, timber, fruits, edible roots, bark and leaves, and human and ethnoveterinary medicines [33–36]. Competitive use increases vulnerability to overutilisation, unsustainable harvesting, and mismanagement.
