Effect of Ambient and Black-Globe Temperature on Plasma Prolactin Levels in Ewes Grazing Endophyte-Free and Endophyte Infected Ryegrass

  • L. R. Fletcher
  • B. L. Sutherland
  • C. G. Fletcher

Abstract

Reduced plasma prolactin levels are one of the more consistent responses in animals grazing ryegrass and tall fescue with endophyte. The ergopeptine alkaloid, ergovaline is believed to be responsible. A selected endophyte, AR6 (formerly 187 BB), produces higher levels of ergovaline than its wild-type counterpart (Davies et al., 1993). Prolactin levels in healthy sheep tend to increase as photoperiod, ambient temperature and consequent heat load on the animal increase. However ambient temperature takes no account of the heat increment due to solar radiation or relative humidity.

Keywords

Prolactin Level Tall Fescue Plasma Prolactin Plasma Prolactin Level Endophyte Infect 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

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Copyright information

© Springer Science+Business Media New York 1997

Authors and Affiliations

  • L. R. Fletcher
    • 1
  • B. L. Sutherland
    • 1
  • C. G. Fletcher
    • 1
  1. 1.AgResearch, Grasslands, LincolnLincolnNew Zealand

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