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