Great Lakes Dairy Sheep Symposium - the Department of Animal ...

that there have not been enough studies to use sheep faeces as a nutritional indicator with high
confidence. For this reason, his classification should be used with some caution.
Grazing Methods to Maximize the Animal Yield and Stocking Rate
Grazing is a system where there are complex interactions between the animal, the sward,
the shepherd, the soil and the climate (Figure 6).
sheep
climate
Figure 6 – Grazing as a complex system.
shepherd
Based on Van Soest (1994) classification, sheep are considered grass-roughage eaters.
When sheep are allowed to graze in woodlands, DM from grass forms up 90% of their diet. In
similar conditions goats obtain 60% of their diet from woody species (Table 12). In addition,
there is a 35% overlap in the diet composition of sheep and goats in winter, and 60% in spring
(Leclerc, 1985).
Table 12 – Sheep and goats diet composition in a mixed flock in Corse, France (Leclerc, 1985).
Species Sheep Goats
Wood 7% 61%
Graminacee 64% 16%
Other herbaceous species 29% 23%
Managing lactating ewes under grazing conditions means optimising feed resources to
satisfy their nutritional requirements, taking into account their feeding behaviour. Grazing is
basically the interaction between the animals using the sward and the sward itself. The grazing
behaviour of herbivores is strongly influenced by the characteristics of the sward and its growth
habit, growth rate and eco-physiological development are determined by the stocking density
(Molle et al., 2004). Thus two quantities have to be assessed in order to choose the right grazing
management system: a) the DM availability of sward and b) the intake of herbage by sheep. The
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sward
soil