HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Spiers, D. E. Articles by Rottinghaus, G. E. Search for Related Content PubMed PubMed Citation Articles by Spiers, D. E. Articles by Rottinghaus, G. E.

A model of fescue toxicosis: Responses of rats to intake of endophyte-infected tall fescue^1,2

D. E. Spiers^*,3, P. A. Eichen^* and G. E. Rottinghaus

^* Animal Sciences Unit, and and Veterinary Medical Diagnostic Laboratory, University of Missouri, Columbia 65211

³ Correspondence: 114A Animal Science Research Center (phone: 573-882-6131; fax: 573-882-6827; e-mail: spiersd{at}missouri.edu).

A study was conducted to develop a model for fescue toxicosis using rats fed a diet containing endophyte-infected tall fescue seed (E+). Rats implanted with telemetric transmitters to continuously monitor core body temperature (T_c) and activity were housed at thermoneutrality (21°C) and were fed a diet containing endophyte-free fescue seed (E–). After 2 wk, they were assigned to either E+ or E– diets and initially maintained at thermoneutrality (preheat) for 8 d. They were then exposed to heat stress (31°C) for 22 d, followed by 1 wk of recovery at thermoneutrality (post-heat). Body weight and feed intake were measured daily. Rats receiving the E+ diet showed decreased feed intake (P = 0.001) and weight gains (P = 0.003) during the preheat period. The decrease in T_c from the pre-treatment level was greater in E+ than in E– rats during the preheat (P = 0.001) and postheat (P = 0.001) periods. With heat stress, both groups showed parallel decreases in feed intake. The increase in T_c from pre-heat to heat conditions was greater in E+ vs. E– rats (P = 0.001). Activity level was lower in E+ than in E–rats during heat stress (P = 0.009) and postheat (P = 0.037) periods. These results show that the rat model for fescue toxicosis is extremely useful because many of the observed responses to E+ diet are similar to those noted for cattle, and additional variables that are difficult to measure in cattle, such as activity, can be easily evaluated.

Key Words: Heat • Neotyphodium • Rat • Tall Fescue • Temperature

This article has been cited by other articles:

				R. S. Settivari, T. J. Evans, L. P. Yarru, P. A. Eichen, P. Sutovsky, G. E. Rottinghaus, E. Antoniou, and D. E. Spiers Effects of short-term heat stress on endophytic ergot alkaloid-induced alterations in rat hepatic gene expression J Anim Sci, October 1, 2009; 87(10): 3142 - 3155. [Abstract] [Full Text] [PDF]

				S. Bhusari, Z. Liu, L. B. Hearne, D. E. Spiers, W. R. Lamberson, and E. Antoniou Expression Profiling of Heat Stress Effects on Mice Fed Ergot Alkaloids Toxicol. Sci., January 1, 2007; 95(1): 89 - 97. [Abstract] [Full Text] [PDF]

				R. S. Settivari, S. Bhusari, T. Evans, P. A. Eichen, L. B. Hearne, E. Antoniou, and D. E. Spiers Genomic analysis of the impact of fescue toxicosis on hepatic function J Anim Sci, May 1, 2006; 84(5): 1279 - 1294. [Abstract] [Full Text] [PDF]