The development and use of new vascular bioassays based on vasculature from disparate regions in the bodies of the animals (e.g., core vs. peripheral tissue) as well as bioassays for other physiological systems are needed to delineate fully the alkaloids responsible for the complete fescue toxicosis syndrome and the mechanisms of intoxication. Accurate, sensitive, and logistically favorable analytical protocols are needed to track the alkaloids and their metabolism throughout the body to understand the toxicokinetics and dynamics of the toxicants to the animal. Only recently have researchers begun to use genomic, proteomic, and metabolomic tools to study the effects of tall fescue toxicants on cellular/organismal function and performance (Bhusari et al., 2006; Settivari et al., 2006; Jones et al., 2004). The increased application of these tools to the problem of tall fescue toxicosis offers opportunities to elucidate more completely the molecular consequences of intoxication and subsequently will aid in the selection of prophylactic and treatment protocols for the disease.
Plane of nutrition and/or toxicants found in E+ tall fescue could affect microbial activity in both the rumen and the cecum, thereby potentially moderating the effects of the toxicants on digestion. Direct alterations of ruminal function resulting from tall fescue ingestion have been demonstrated, but not directly linked to the endophyte. Therefore, it is critical that additional research be conducted concerning not only the effects of the alkaloids on rumen function but of the plane of nutrition on the metabolism of the compounds. Evaluation tools such as Doppler ultrasound imaging are needed that provide immediate measures of basic physiological functions as affected by the consumption of E+ tall fescue. These tools would help validate the in vitro bioassays and cell culture methods being used to dissect the mechanisms of action.