When there was a difference it was always in favour of E+. More E+ plants (mean 1.2) survived a period of water stress than E- plants (mean 0). Sheep live-weights were lower in E+ during a four week period of staggers in one year (E+ 28.0 kg and 28.7kg; E- 29.6 kg and 30.4 kg on 7 and 24 May 1996 respectively), but compensatory gain occurred after the period of staggers. In the following year when staggers was not evident, E+ sheep gained weight at a faster rate than E-. A large effect in the incidence and severity of ryegrass staggers was related to botanical composition and the percentage intake of E+ perennial ryegrass in the diet at that time. The effect of N. lolii on faecal moisture levels was not consistent and there was no effect wool production. There was no consistent difference in the grazing preference between E+ and E- by sheep, beef cattle or horses except on one occasion when E- appeared to have a higher infection of the foliar leaf-spot Pyrenophora semeniperda and sheep preferred to graze E+. Plots with low initial N. lolii infection rates increased in infection over time, with some large increases evident (1467%, 667%, 467%).
|Qualification||Doctor of Philosophy|
|Place of Publication||Australia|
|Publication status||Published - 2009|