Evaluation of Rival, Venture and Frontier reed canarygrass as pasture forage

Abstract

A grazing study was conducted to determine productivity of the grazing animal on reed canarygrass (RCG) pasture. A total of six 0.5-ha paddocks assigned to three RCG cultivars identified as Rival, Venture and Frontier were used in the 2-yr study. Forage nutrient and alkaloid concentrations and animal performance were monitored under continuous grazing conditions. Above average temperatures and precipitation levels that were 60% of normal were encountered in the first grazing season, resulting in relatively high forage crude protein levels but also high alkaloid concentrations. Animals grazing Frontier paddocks exhibited a high incidence of scouring, preferential grazing and low body-weight gains in the first half of the grazing season. Excessive gramine levels (> 2.0 mg g−1 DM) were observed in all three RCG cultivars during a major portion of this grazing season. A 56-d finishing trial at the end of the grazing season indicated that lambs did not have carryover or residual effects associated with long-term exposure to excessive levels of gramine. Improved growing conditions in the second grazing season resulted in improved pasture carrying capacities, reduced incidence of scouring and no differences among RCG cultivars for animal weight gain. During both grazing seasons, animals grazing Venture paddocks exhibited good weight gains in the initial part of the grazing season, relative to the other cultivars, but weight gains declined more rapidly for animals grazing this cultivar relative to Rival and Frontier as the grazing season progressed. Key words: Reed canarygrass (Phalaris arundinaceae L.), gramine, hordenine, drought, pasture