Influence of alkaloid content on intake of subspecies of Chamaecytisus proliferus

Alkaloid contents (sparteine accounted for more than 80%) of four subspecies of Chamaecytisus proliferus (tagasaste) were higher in spring cuts than in autumn cuts, and they were (g kg−1 DM for spring and autumn cuts, respectively) 2.9 and 1.6 for palmensis subspecies, 7.3 and 2.9 for canariae, 11.3 and 7.9 for meridionales and 2.7 for the autumn cut of calderae. Voluntary intake was determined by free-choosing among subspecies cuts. Intake of tagasaste subspecies ranged between 3.7 and 9.2 g DM kg−1 BW0.75, and was negatively correlated (r=−0.92, p<0.01) with alkaloid content of subspecies, but not with chemical composition or ruminal degradability of nutrients. Alkaloid content of subspecies could explain the erratic intake of tagasaste.