TY - JOUR
T1 - Australian perennial shrub species add value to the feed base of grazing livestock in low- to medium-rainfall zones
AU - Revell, Dean
AU - Norman, H.C.
AU - Vercoe, Phil
AU - Phillips, N.
AU - Toovey, A.F.
AU - Bickell, Samantha
AU - Hulm, E.L.
AU - Hughes, S.J.
AU - Emms, J.
PY - 2013
Y1 - 2013
N2 - Australian native perennial shrubs that are adapted to drought and infertile soils contribute nutrients to grazing systems that would otherwise support limited ruminant productivity. In this study, we report the nutritive value of 39 Australian shrub species of the genera Atriplex, Rhagodia, Maireana, Chenopodium, Enchylaena, Acacia, Eremophila, and Kennedia. Edible foliage was sampled in winter and summer, and there was little difference in nutritive value between seasons. The in vitro organic matter digestibility of most shrub species was 40-70%. Most species contained medium to high levels of crude protein (12-22% of dry matter, DM) and high concentrations of sulfur (2-8 g/kg DM). In an 8-week grazing experiment in which Merino wethers grazed a 'shrub system' containing four shrub species and a sown inter-row of annual pasture, the sheep gained weight during autumn without supplementary feeding. By comparison, sheep fed senesced volunteer pasture and supplementary cereal grain only maintained weight. The forage shrubs provided up to 50% of the total DM intake of sheep grazing the 'shrub system' and made a modest contribution to the digestible energy intake of the animals and a large contribution to their crude protein and mineral intake. Considering the timely and predictable provision of limiting nutrients and benefits such as gut health and the provision of shade and shelter, we suggest that Australian shrub species can make a valuable addition to the feed base of low- to medium-rainfall zones in southern Australia. © CSIRO 2013.
AB - Australian native perennial shrubs that are adapted to drought and infertile soils contribute nutrients to grazing systems that would otherwise support limited ruminant productivity. In this study, we report the nutritive value of 39 Australian shrub species of the genera Atriplex, Rhagodia, Maireana, Chenopodium, Enchylaena, Acacia, Eremophila, and Kennedia. Edible foliage was sampled in winter and summer, and there was little difference in nutritive value between seasons. The in vitro organic matter digestibility of most shrub species was 40-70%. Most species contained medium to high levels of crude protein (12-22% of dry matter, DM) and high concentrations of sulfur (2-8 g/kg DM). In an 8-week grazing experiment in which Merino wethers grazed a 'shrub system' containing four shrub species and a sown inter-row of annual pasture, the sheep gained weight during autumn without supplementary feeding. By comparison, sheep fed senesced volunteer pasture and supplementary cereal grain only maintained weight. The forage shrubs provided up to 50% of the total DM intake of sheep grazing the 'shrub system' and made a modest contribution to the digestible energy intake of the animals and a large contribution to their crude protein and mineral intake. Considering the timely and predictable provision of limiting nutrients and benefits such as gut health and the provision of shade and shelter, we suggest that Australian shrub species can make a valuable addition to the feed base of low- to medium-rainfall zones in southern Australia. © CSIRO 2013.
U2 - 10.1071/AN13238
DO - 10.1071/AN13238
M3 - Article
VL - 53
SP - 1221
EP - 1230
JO - Australian Journal of Experimental Agriculture
JF - Australian Journal of Experimental Agriculture
SN - 0816-1089
IS - 11
ER -