Publication Date
1997
Description
The aim of this study was to compare the milk production of cows grazing endophyte-infected perennial ryegrass (Lolium perenne L.) pasture with those grazing endophyte-free pastures. High and nil endophyte ryegrass pastures were drilled with and without white clover (Trifolium repens L.) in autumn 1993. White clover was completely removed in autumn 1995. High endophyte pastures had >85% of tillers infected but nil endophyte pastures were rapidly contaminated with endophyte-infected ryegrass and had 50% infection by autumn 1996. Losses in milk production due to endophyte were small (<6%), and occurred in only 2 of the 6 three week test periods. Cows showed clinical symptoms of ryegrass staggers in summer/autumn 1995 but not in 1996. Heat stress symptoms were absent. Losses of milk production occurred when lolitrem B levels were low (spring 1994) and when cows did not show clinical staggers (summer 1996). Other chemicals or agronomic factors could be important determinants of the milk production responses.
Citation
Thom, E R.; Clark, D A.; Waugh, C D.; McCabe, R J.; van Vught, V T.; and Kock, B.J L., "The Effect of Ryegrass Endophyte on Milk Production from Dairy Cows in Northern New Zealand" (2024). IGC Proceedings (1993-2023). 30.
https://uknowledge.uky.edu/igc/1997/session11/30
Included in
Agricultural Science Commons, Agronomy and Crop Sciences Commons, Plant Biology Commons, Plant Pathology Commons, Soil Science Commons, Weed Science Commons
The Effect of Ryegrass Endophyte on Milk Production from Dairy Cows in Northern New Zealand
The aim of this study was to compare the milk production of cows grazing endophyte-infected perennial ryegrass (Lolium perenne L.) pasture with those grazing endophyte-free pastures. High and nil endophyte ryegrass pastures were drilled with and without white clover (Trifolium repens L.) in autumn 1993. White clover was completely removed in autumn 1995. High endophyte pastures had >85% of tillers infected but nil endophyte pastures were rapidly contaminated with endophyte-infected ryegrass and had 50% infection by autumn 1996. Losses in milk production due to endophyte were small (<6%), and occurred in only 2 of the 6 three week test periods. Cows showed clinical symptoms of ryegrass staggers in summer/autumn 1995 but not in 1996. Heat stress symptoms were absent. Losses of milk production occurred when lolitrem B levels were low (spring 1994) and when cows did not show clinical staggers (summer 1996). Other chemicals or agronomic factors could be important determinants of the milk production responses.
