CHEMICAL COMPOSITION AND NUTRITIVE VALUE OF BUCKWHEAT CULTIVARS FOR LABORATORY RATS

Abstract

Experiments were conducted to determine the nutritive value of selected buckwheats in comparison with common buckwheat or tartary buckwheat. A 21-day, growth trial was conducted in which 42 Spraque-Dawley rats (initial weight 57 g) were randomly assigned to one of seven dietary treatments. Experimental diets contained the buckwheat cultivars, Mancan, Tempest and Tokyo, two unselected forms of common buckwheat (common and CM 169), tartary buckwheat or a casein control. Diets were formulated to supply 10% crude protein by dilution of the test protein with varying levels of a basal diet. An additional 36 rats were utilized in digestibility studies. There was little difference in chemical composition, mineral content, level of indispensable amino acids or digestibility coefficients between selected and unselected varieties of common buckwheat, while tartary buckwheat had lower levels of crude protein, lower indispensable amino acids, higher acid detergent fiber levels and lower apparent digestibility coefficients for dry matter, crude protein and energy. Weight gain and feed conversion efficiency were significantly (P < 0.05) improved for rats fed the selected varieties of buckwheat in comparison with those fed the common or tartary buckwheat. The overall results suggest that the selected cultivars of common buckwheat will support improved animal performance. Key words: Buckwheat, rats, nutritive value, digestibility