Animal performance and economic comparison of novel- and toxic-endophyte tall fescues to cool-season annuals

¹ Southwest Research and Extension Center, Hope, AR 71801
² Department of Animal Science, Fayetteville, AR 72701
³ Department of Crops Soils and Environmental Sciences, Fayetteville, AR 72701
⁴ Department of Agricultural Economics, Rice Research and Extension Center, Stuttgart, AR 72601
⁵ Livestock and Forestry Branch Station, Batesville, AR 72501

^* To whom correspondence should be addressed. E-mail: pbeck{at}uaex.edu.

	Abstract

Increased costs of annual establishment of small grain pasture associated with fuel, machinery, and labor are eroding the profitability of stocker cattle enterprises. Interest has therefore increased in development of cool-season perennial grasses that are persistent and high quality. This study occurred on 24 ha (divided into thirty 0.81ha paddocks) located at the University of Arkansas Division of Agriculture Livestock and Forestry Branch Station, near Batesville, AR. Two tall fescue (Festuca arundinacea, Shreb.) cultivars infected with novel endophytes (NE), Jesup infected with AR542 endophyte (Jesup AR542) and HiMag infected with Number 11 endophyte (HM11) were established in September 2002. Jesup AR542 and HM11 were compared to endemic endophyte Kentucky 31 (KY-31) tall fescue, wheat (Triticum aestivum L) and cereal rye (WR, Secale cereale L.) planted in September 2003, 2004, and 2005, and annual ryegrass (RG, Lolium perenne L. ssp. multiflorum (Lam.) Husnot) planted in September 2004 and 2005. Each year, 3 steers (3.7 steers/ha) were placed on each pasture for fall and winter grazing and 5 steers (6.2 steers/ha) were placed on each pasture for spring grazing. Animal performance is presented by year in the presence of a year by treatment interaction (P < 0.01). Body weight gain/ha of NE tall fescue was greater (P < 0.01) than KY-31 and WR during 2003 to 2004; while in 2004 to 2005, BW gain/ha of NE and RG did not differ (P 0.29) and was greater (P < 0.01) than WR which was greater (P < 0.01) than KY-31. During 2005 to 2006, BW gain/ha was greater (P < 0.01) for RG than NE and WR which did not differ (P 0.14). Body weight gain/ha was least (P < 0.01) for KY-31. Average net return of NE tall fescue was greater (P < 0.01) than KY-31, but profitability of NE did not consistently differ from cool-season annuals. Across the 3-yr study, NE tall fescue produced net returns/ha of $219; this level of profitability would require 4 yr for a new planting of NE tall fescue to breakeven. Novel endophyte tall fescues offer potential benefits related to decreased risk of stand establishment of annual forage crops, longer growing season, and acceptable animal performance.

Key Words: cattle, Festuca arundinacea Shreb., Lolium perenne L. ssp. multiflorum (Lam.) Husnot, Neotyphodium ceonophialum, N. lolii, Secale cereale L., Triticum aestivum L.