Mechanical Disruption of Leaf Tissues and Cells in Some Bloat‐Causing and Bloat‐Safe Forage Legumes1

Abstract

Whole leaves and isolated mesophyll cells from three bloat‐causing and three bloat‐safe legumes were mechanically damaged to identify characteristics which might contribute in resisting cell and tissue rupture during chewing and hence reduce bloat potential. Whole leaves were subjected to sonication, homogenizing with a ground glass tissue grinder, and shaking with glass beads. Isolated cells were exposed only to rupture by sonication. In the bloat‐safe legumes, birdsfoot trefoil (Lotus corniculatus L.) had strong cell walls alone, while sainfoin (Onobrychis viciifolia Scop.) and cicer milkvetch (Astragalus cicer L.) revealed moderately strong cell walls combined with a high degree of tissue strength. The bloat‐causing legumes, alfalfa (Medicago sativa L.) and white clover (Trifolium repens L.) showed weak cell walls with low tissue strength while red clover (T. pratense L.) had moderately strong cell walls and low tissue strength. Cell wall strength alone or combined with tissue strength appears to be a factor in determining cell rupture.