Nutritive value of wheat varieties fed to non-ruminants

Abstract

1. Wheats grown during the 1991 and 1992 harvest were evaluated for starch and proximate composition together with dietary energy (Apparent Metabolisable Energy, AME in young poultry; True Metabolisable Energy, TME in adult and young poultry; Digestible Energy, DE, in growing/finishing pigs) and nitrogen digestibility in growing/finishing pigs.

2. Starch and nitrogen levels varied considerably.

3. TME data indicated no meaningful variation attributable to variety, year of growth, location of growth or nitrogen fertiliser. TME data obtained with old birds were generally higher than that for young birds and the latter were associated with greater variability.

4. AME values were dependent upon the rate of inclusion of wheat in diets. AME data varied considerably between individual samples, although there was no clear evidence associating extreme values with specific named varieties. A possible effect of season was identified, but the influence of nitrogen fertiliser was negligible. The effect of site of growth was variable.

5. There was little correlation between TME (old and young) and AME.

6. DE values differed significantly between varieties, but not in a consistent pattern. The effect of season and location of growth appeared small. There was evidence that nitrogen digestibility improved with total nitrogen content.

7. There were no correlations obtained between AME and proximate analysis, bushel weight, 100 grain weight or Hagberg Falling Number. In addition the use of NIRS to predict AME was unsuccessful.