Evaluation of Stylosanthes scabra Accessions as Forage Source for Ruminants: Growth Performance, Nutritive Value and In Vitro Ruminal Fermentation

Feed shortage is the main cause of poor production performance in livestock under smallholder farmer’s in South Africa. Therefore, this study evaluated the growth performance, nutritive value and in vitro ruminal fermentation of Stylosanthes scabra accessions in climatic condition of Pretoria, South Africa as potential forage sources in order to improve feed quality and subsequently livestock production. Stylosanthes scabra accessions were planted in 6 m2 plots following a complete randomized block design with three replicates per accession. The plants were allowed to grow to full maturity after which forage was harvested and yield, chemical composition, phenolic compounds, in vitro organic matter digestibility (IVOMD) and in vitro ruminal fermentation characteristic were determined. Forage yield of accessions ranged between 4.3 to 5.3 t ha−1 in dry matter (DM), and only twelve accessions were identified to be adaptable over the three-year evaluation under rain-fed. Accessions 140, 9281, 11,252, 11,595, 11,604 and 11,625 were consistent in terms of forage yield over the three years. Significant differences among accessions were observed for crude protein (CP), neutral detergent fiber (NDF), IVOMD, metabolizable energy, metabolizable energy yield, gas production, total phenols, total hydrolysable tannins and total condensed tannins. Principal component and clustering analysis showed that accessions 11,255 and 11,625 are distinct in their characteristics as compared to the rest of the accessions, and both accessions are suitable forage source for animals since they contain low NDF with good forage production and crude protein content. However, there is a need for further study to integrate these accessions into the feeding systems in order to improve livestock production.

Clearing confusion in Stylosanthes taxonomy: 1. S. seabrana B.L. Maass & 't Mannetje

Stylosanthes seabrana was first formally described as a new species in 2002 following extensive morphological and agronomic characterization, accompanied by genetic and molecular studies. Since then it has been proposed as a synonym of Stylosanthes scabra Vogel. This paper refutes this synonymization and indicates the indisputable evidence that S. seabrana, a diploid, is a likely putative progenitor of the allotetraploid S. scabra.

Vegetation change 10 years after cattle removal in a savanna landscape

Following the establishment of a conservation reserve, changes in ground stratum vegetation following removal of cattle were examined in a northern Australian savanna over a 10-year period. The floristic composition of 40 vegetation plots in lowland savannas were surveyed shortly after acquisition of the property, and then surveyed twice in the following 10 years after cattle removal. Some notable ecosystem-transforming introduced species (weeds) such as Themeda quadrivalvis remained relatively stable, whereas the pasture legume Stylosanthes scabra increased in cover. The species richness of both native and introduced plants increased. Various plant functional groups changed in relative cover, with a decline in relatively unpalatable grasses and a corresponding increase in palatable grasses, responses that are consistent with recovery from grazing pressure. Our results show that removal of cattle in highly disturbed savanna ecosystems can have both positive and negative results for native ground stratum vegetation in the first decade of recovery.

Effect of Three Species of Stylosanthes on The Performance of West African Dwarf Sheep

An experiment was conducted to determine the effect of feeding three species of Stylosanthes as supplements to a basal diet consisting of Cyonodon dactylon on the performance of West African dwarf sheep. The three treatments imposed were: Treatment 1, a basal diet consisting of poor quality grass ( Cyondon dactylon ) and Stylosanthes scabra in the ratio of 70:30. Treatment 2, the basal diet added with Stylosan thes guianensis (70:30); and Treatment 3,the basal diet with Stylosanthes hamata (70:30). The study lasted for 24 days, a 10 day adjustment period and a 14- day data collection, using 3 rams of comparable age and weight. Data were analyzed as a 3 x 3 Latin square. Animals supplemented with S. guianensis had the highest DM intake while S. s c a b r a was least consumed by sheep (p<0.05). Digestibility of crude protein and DM however showed that animals on S. guianensis performed better. It could be concluded that sheep can be supplemented with Stylosanthes guianensis in the savannah zone of Nigeria.