Quality of wild herbaceous legumes and its role in livestock nutrition

Abstract

Climate change in southern Africa is predicted to be severe, and animal agriculture will suff er the most. However, there exist wild legumes that have survived under harsh environmental conditions and contribute to a varied diet for the grazing ungulates. This study tested the chemical composition of four wild herbaceous legumes each from Tswapong and Ngamiland districts in Botswana (Chamaecrista abscus, Chamaecrista rotundifolia, Crotalaria sphaerocarpa, Tephrosia lupinifolia, Tephrosia purpurea, Indigofera sp., Zornia glochidiata.). These plant species were previously found to fi x nitrogen in the soil by the SASSCAL research Task 316, and the plant selection was also guided by informed focus discussions with farmers. For Tswapong the results show that C. rotundifolia and T. purpurea had the highest level of crude protein (CP) while Z. glochidiata had the least CP. In vitro gas production showed high gas yield for Z. glochidiata, and a small volume of gas was produced by T. lupinifolia. Condensed tannins (CT) were higher for Z. glochidiata and C. rotundifolia but lower for T. purpurea and T. lupinifolia. CT were at similar concentration for C. rotundifolia and Z. glochidiata. No relationship was detected between condensed tannins and crude protein. With regard to samples from Ngamiland, there was no diff erences among plant species for acid detergent fi bre (ADF), whereas other parameters measured were signifi cantly diff erent among the legume plants. Indigofera sp. had the highest CP, while Crotalaria sphaerocarpa had the lowest. In general, levels of crude protein were diff erent among the legumes investigated but overall were higher than in natural grass, indicating their importance in providing protein to grazing ungulates in rangelands. Their high protein content also suggests the plants' potential as protein supplements if domesticated as fodder crops. However, palatability, toxicity, and intake should be tested in future studies before any recommendations are made.Resumo: Prevê-se que as alterações climáticas no Sul de África sejam severas, e a agricultura animal será a que irá sofrer mais. Porém, existem leguminosas silvestres que sobreviveram sob condições ambientais severas e contribuem para uma dieta variada dos ungulados de pastagem. Este estudo testou a composição química de quatro leguminosas herbáceas silvestres, cada uma dos distritos de Tswapong e Ngamiland no Botswana (Chamaecrista abscus, Chamaecrista rotundifolia, Crotalaria sphaerocarpa, Tephrosia lupinifolia, Tephrosia purpurea, Indigofera sp., Zornia glochidiata). Foi previamente descoberto pela equipa de trabalho 316 do SASSCAL que estas espécies de plantas fi xam azoto no solo, tendo a selecção de plantas sido também guiada por discussões de foco informado com agricultores. Para Tswapong, os resultados mostram que C. rotundifolia e T. purpurea tiveram os níveis mais elevados de proteína bruta (CP), enquanto que Z. glochidiata teve a menor quantidade de CP. In vitro, a produção de gás mostrou um elevado rendimento pela Z. glo...

Effect of Plant Spacing on Agronomic Performance and Fodder Quality of Four Tepary Bean (Phaseolus acutifolius A. Gray) Cultivars

“…Castro-Montoya et al [58] demonstrated that legume crop residues improve dry matter intake in dairy cattle than sorghum silage when fed in total mix ration. Legume forages have a higher nutritive value when compared to grasses especially during the dry season [59,60]. In semiarid environments, seasonal-constant changes in the nutritional quality of natural pastures compromise livestock quality and lead to the inclusion of leguminous plants as supplements [61].…”

What is quality for a ruminant? A short introduction to the meaning of plant chemical composition measurements

“…This process might be benefi cial as non-organic nitrogen from urea is already transferred into amino acids by the rumen microbes. The amino acids can be used by the ruminant to form body´s own protein, instead of building amino acids by themselves in the fi rst step (see also Madibela et al, 2018).…”

“…These contradictions between positive and negative eff ects might be explained by the diff erences in chemical structure as the term "tannins" describes a large group of diff erent substances and every plant species has its own composition. More information about tannins is given in Madibela et al (2018).…”

Rangeland monitoring and assessment: a review

“…However, small shrubs and herbs, such as Monechma genistifolium and diff erent wild legumes, often serve as food for wild herbivores. They can also be an additional, supplementary, alternative food resource for livestock, for example in the dry season when food availability is restricted (Madibela et al, 2018). Their utilisation by herbivores, as well as their general nutritional quality, is poorly known.…”