This case study also uses a representative farm model to gain insights about the role of perennial pastures in a farming system. It builds on the previous example by including a number of perennial pastures with different characteristics.
The case study farm is representative of farms on the south coast. Four pasture types are included: annual pasture, lucerne, kikuyu and a (temperate or summer-active) tall fescue.
Two livestock systems are considered: a self-replacing Merino flock for wool production only and a self-replacing Merino flock using excess ewes for crossbred lamb production. (Note: These are the same as flock types (i) and (ii) in case study 1, Table 2.)
The average annual rainfall is 600 mm with 70% falling between April and October. Soil types include deep sands, duplex soils susceptible to waterlogging and moderately deep sandy duplex soils.
Results:
Including perennial pastures increases profit, with the increase in profit higher for the SRF XB flock than the wool-only flock. This indicates that high quality perennial pastures are best used in a livestock system that focuses on meat production rather than on one based mostly on wool production.
For both flock types there is an increase in stocking rate, pasture use and pasture growth and a decrease in supplementary feeding as the perennial pasture types included are increased from two to three (Table 5).
Perennial pastures enable higher stocking rates by providing higher and more-timely pasture growth (Table 5). The total area of perennial pasture can be increased when more perennial pasture types, with different seasonal growth patterns, are included to fill various niches within the farming system (Figure 2).
Summary:
- The optimal area sown to perennial pastures depends on the livestock enterprise and the mix of perennial pastures.
- There is a wide range (50-90% of total farm area) over which profit is insensitive to the area of perennial pastures.
- A mix of perennial pastures provides a range of feed availability due to their different seasonal growth patterns.
- Perennial pastures help fill the summer/autumn feed gap and so reduce the amount of supplementary feed required per animal.
- Pasture growth and pasture utilisation can be increased through better grazing management.
Information Sourced From:
