Atmospheric CO2 is expected to increase to between 550 ppm and 1000 ppm in the next century. CO2-induced changes in plant physiology can have ecosystem-wide implications and may alter plant-plant, plant-herbivore and plant-symbiont interactions. We examined the effects of three concentrations of CO2 (390ppm, 800ppm and 1000ppm) and two concentrations of nitrogen fertilizer (0.004gN/week vs. 0.2...

Six Holstein steers (313 +/- 10 kg BW) surgically fitted with hepatic portal, mesenteric venous, mesenteric arterial, and hepatic venous catheters were used in a replicated crossover design experiment to evaluate the feeding of Acremonium coenophialum-infected fescue hay on portal-drained visceral and hepatic nutrient metabolism. Only four steers had functional hepatic catheters. Infected (INF)...

Fescue toxicosis in livestock is due to ingestion of endophyte (Acremonium coenophialum) -infected tall fescue. Understanding mechanisms responsible for decreased calving and growth rates, delayed onset of puberty, and impaired function of corpora lutea in heifers at puberty consuming endophyte-infected fescue is an emerging field in reproductive toxicology. The condition decreases overall prod...

Tall fescue (Festuca rundinacea) plants can be infected with the endophytic fungus Acremonium coenophialum. This fungus, which grows subcutaneously in leaves, stems, and seeds, does not undergo sexual reproduction or sporulate, and cannot survive outside the plant (Clay 1988). The fungus is passed from one generation to the next through infected seed. A mutualistic relationship exists between t...