Influence of the ryegrass endophyte (neotyphodium lolii) in a cool-moist environment ii. sheep production

Abstract

The impact of the ryegrass endophyte on sheep production in a cool moist environment was examined in a field experiment in Southland, New Zealand. Ryegrass staggers were observed in one year when drought conditions were experienced, but not in years with average summer rainfall. There was a negative correlation (r = -0.9) between ryegrass staggers score and liveweight changes in animals forced to consume a high proportion of basal plant material, and animals grazed endophyte-infected pastures less closely than endophyte-free pastures. Lamb liveweight gains were not significantly affected by the presence of endophyte, except when drought conditions were experienced, although this is probably more a reflection of differences in pasture composition than of a direct endophyte effect. Faecal soiling was higher (P = 0.052) on endophyte-infected pastures, especially under drought conditions (P = 0.025), and wool yields on mixed ryegrass/white clover pastures were 10% higher on endophyte-free than on endophyte-infected pastures (P = 0.003). There was no evidence of an endophyte effect on fat deposit. It is concluded that the endophyte had moderate negative effects on animal production in a cool moist environment. © 1998 Taylor & Francis Group, LLC.