Effects of novel ryegrass endophytes on pasture production and milk production from dairy cows in northern New Zealand

摘要

The fungal endophytes AR1 and AR37 have been selected to provide insect protection for perennial ryegrass ( Lolium perenne L.) with less animal toxicity (eg ryegrass staggers) than is associated with the wild‐type (WT) endophyte.AR1 is non‐toxic to ruminants while AR37 contains a less potent animal toxin than WT.Cows eating ryegrass infected with AR1 produced 9% more milk than those eating WT over 3 years despite no differences in pasture nutritive value or yield (Bluett et al.,2005).AR37 controls a broader range of insects than AR1.It is currently being tested in short‐term feeding experiments indoors and under rotational grazing ( Thom et al.,2007) that commenced in 2005.This paper reports some of the early results from this experiment.