Project Number: 6227-32630-001-31
Project Type: Specific Cooperative Agreement

Start Date: Feb 15, 2008
End Date: Feb 14, 2013

Objective:
The overall objective of this research is to minimize economic losses from fescue toxicosis. Specific objectives include: 1) development of plant germplasm that is both non-toxic and persistent, which could involve germplasm infected with novel endophytes or germplasm that is endophyte-free; 2) development of management practices that improve animal performance and reduce effects of heat stress associated with fescue toxicosis in animals; 3) further evaluation of fescue toxicosis effects on animal physiology and recovery from this condition; and 4) identification of markers of animal sensitivity to heat stress and fescue toxicosis.

Approach:
Tall fescue, infected with endophytes that do not produce animal toxic alkaloids, will be tested for animal toxicosis in feeding and grazing trials. Persistence of new germplasms will be measured in grazed pastures. Forage management practices will be developed to control and reduce toxicity of tall fescue. Endophyte-free germplasm with increased concentrations of plant proteins associated with nematode resistance will be tested for persistence. New approaches to monitor body temperature will be established and used to evaluate techniques for reducing heat stress. Treatments that promote healthy immune systems, like antioxidant activity and body temperature regulation, will be assessed for effects on severity of fescue toxicosis under field and in climate-controlled environmental chambers. Genetic and physiological markers of animal sensitivity to heat stress and fescue toxicosis will be identified to improve selection of animals that are more resistant to these problems.