The Determination of the Composition or Purity of Animal Feeding Stuffs by Microscopy

The Determination of the Composition or Purity of Animal Feeding Stuffs by Microscopy b7 J. Hunrnr HAr.rsNcr (Dr, Bemard Dyer and Partners Ltd,,20 Eastcheap, London, E.C.3) The use of lobelia seeds for evaluation of areas of characte stic fibres in the estimation of the constituents of animal feeding stuffs, is descdbed. The fibre constituents of most animal feeding stuffs have speciflc micro- scopical characteristics which are invaluable in their detection. and also in assessing their purity. _ In this laboratory the fibre portion is prepared by boiling the finely ground cake or meal (ground to pass the 1-mm sieve) successively with acid and alkali following the procedure laid down in the Fertilisers and Feeding Stuffs Regula- tions. The fibrous tissue remaining after the alkali treatment is washed -with water and then with 1 per cent. Portions of the prepared fibre are then placed between two microscope slides and examined under a l-inch objective.