EVALUATION OF WHOLE PLANT FABABEAN FORAGE IN RUMINANT RATIONS

Abstract

Feeding trials were conducted to evaluate nutritive value of whole plant fababean (FB) silages. A growth trial with dairy heifers resulted in higher consumption (P < 0.05) of FB silage than a grass-legume (GL) silage, with no difference (P > 0.05) in average daily gain (ADG). Lactating Holstein cows were fed four diets, 1-GL + high grain (HG) (control diet), 2-direct cut FB (33% DM) + HG, 3-wilted FB (37% DM) + HG and 4-wilted FB + medium grain (MG), in a Lucas design. Consumption of the direct cut FB silage was higher (P < 0.05) than that of grass silage, and reducing the level of grain feeding from 56 to 43% of the diet resulted in an increase (P < 0.05) in FB silage consumption. Wintering calves were fed five silages (1-FB, 2-GL, 3-barley-clover (BC), 4-corn or 5-barley) plus 1 kg grain supplement for 93 days. Calves receiving FB or GL silage consumed more (P < 0.05) DM than animals on the other treatments. In trial 2, beef calves were fed four silages (early FB, frosted FB, corn or GL) or two types of dehydrated cubes (FB or allalfa). Frosted FB silage have a higher (P < 0.01) ADG compared with the other treatments. Intakes of DM were similar for both FB silages and alfalfa cubes but higher than in GL or corn silage treatments. Feed efficiency ratio was smaller (P < 0.05) for frosted FB than GL silage or dehydrated cubes and similar to the early FB and corn silages. Finishing steers were fed three silages (FB, GL or corn) free choice plus a barley supplement at 1% of body weight. Total DM intake and ADG were higher (P < 0.01) for steers receiving FB silage than for those fed the GL or corn silage. Energy digestibility of FB silage as measured by sheep digestion trials over 2 crop yr and three silage samples was 69.4% ± 2.3, and digestible energy content of FB was similar to that of corn silage.