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The potential contribution of plant secondary compounds to the control of intes-
tinal parasites, thus reducing our reliance on chemical drenches, is based on evi-
dence in vitro that they inhibit the development and motility of the larvae of key
parasitic nematodes (Kotze et al. 2009 ; Kotze et al. 2011 ). Moreover, livestock graz-
ing shrub-based systems are less likely to ingest parasite larvae because they spend
less time grazing near the soil surface when foraging.
Silvopastoral systems can mitigate the risk of stress caused by heat and cold, thus
improving productivity (Tucker et al. 2008 ), because they provide shade and shelter,
an essential part of any integrative strategy. The production costs of being outside
the zone of thermal comfort arise through multiple mechanisms, all of which effec-
tively increase the maintenance requirements of an animal. A greater portion of
ingested energy is spent to maintain body temperature when the ambient tempera-
ture is below or above an animal’s zone of thermal comfort – shivering at low tem-
peratures or panting at high temperatures. Other production costs are caused by
changes in feed intake. Below the animal’s lower critical temperature, feed intake

Table 3 Examples of shrub species with anti-methanogenic properties measured using in vitro
batch culture gas production

Botanical name and taxa author Common name

Methane (% of

controla)

Acacia loderi Maiden Broken Hill gidgee, nelia 18

Lotus australis Andrews Austral trefoil 28

Acacia pycnantha (Benth.) Golden wattle 28

Acacia saligna (Labill.) H.L. Wendl. Golden wreath wattle 31

Eremophila glabra (R. Br.) Ostenf. Tar bush 36

Brachychiton gregorii F. Muell. Desert kurrajongs 38

Atalaya hemiglauca (F. Muell.) F. Muell. Ex

Benth.

Whitewood, cattle bush 38

Acacia neriifolia A. Cunn. ex Benth. Oleander wattle 38

Acacia iteaphylla F. Muell. ex Benth. Flinders Range wattle 38

Maireana convexa Paul G. Wilson Mulga bluebush 47

Kennedia eximia Lindl. Red coral vine 56

Maireana brevifolia (R. Br.) Paul G. Wilson Small leaf bluebush,

yanga bush

56

Rhagodia candolleana Moq. Sea berry saltbush 58

Kennedia prorepens (F. Muell.) F. Muell. Purple flowered pea vine 58

Acacia ligulata A. Cunn. ex Benth. Umbrella bush, sandhill

wattle

62

Chenopodium nitrariaceum (F. Muell.) Benth. Nitre goosefoot 62

Rhagodia preissii Moq. Mallee saltbush 71

Chameacytisus palmensis (H. Christ)

F.A. Bisby & K.W. Nicholls

Tagasaste 71

Enchylaena tomentosa R. Br. Barrier saltbush, ruby

saltbush

73

aControl was oaten chaff

Integrated and Innovative Livestock Production in Drylands