Search

Substitution of unextracted sunflower seeds for either 0, 25, 50 or 100% of the soya bean meal in pig diets produced no significant differences in digestible energy or apparent nitrogen retention. However, all diets containing unextracted sunflower seeds had significantly higher digestible nitrogen than the diets containing soya bean meal as the protein source. Replacement of 25% of the soya bean meal with unextracted sunflower seeds produced the greatest increase in digestibility. Rate and efficiency of gain in rats were used to evaluate the effects of autoclaving unextracted sunflower seeds at 115°C with 1.05 kg/cm2 pressure for 0, 5 or 10 minutes. Rats fed on the basal maize-soya bean meal diet gained significantly faster and more efficiently than the rats fed on the diets containing the sunflower seeds. An increase in heating time of the sunflower seeds produced a significant reduction in rate and efficiency of rat gain.

Fourteen grain sorghum cultivars were used to study the degree of relationship between energy and protein digestion coefficients and tristimulus colour values of grain sorghum. Colour values from whole grain, ground dry and ground blended samples of each cultivar were used. Colour values of the ground blended samples were more highly associated with digestibility and nitrogen retention than were colour values of either whole grain or ground dry grain sorghum. Although close relationships were shown by simple correlation coefficients, valid prediction equations could not be developed (P < 0.05) from combinations of these three colour observations. These data indicate that colour difference meter values can be used to develop linear regression equations that would assist in screening grain sorghum cultivars for nutritive value in swine.