ANN 111: Principles of Animal Nutrition and Feed Technology (2+1)

PROCEDURE

• Record the weight of a sintered glass crucible
• Record the weight of the crucible along with approximately 1 g of feed sample.
• Attach the crucible in a reflux system and reflux the sample for one hour with 100ml of neutral detergent solution.
• After refluxing filter and wash the residue.
• Dry the crucibles in a hot air oven overnight and record its weight.
• Reflux the residue with 100 ml of acid detergent solution for one hour.
• Filter and wash the residue.
• Dry the crucibles in a hot air oven overnight and record its weight.
• Add known quantity of asbestos to the residue in the crucible.
• Add little distilled water and make the contents to a smooth paste using a glass rod.
• Place the crucible over an glass /enamel tray and add 50 ml of 72 % sulphuric acid and mix well.
• A blackish coloured liquid will flow out through the pores of the crucible; repeat the addition of sulphuric acid till the liquid is clear and colourless.
• Wash the residue with distilled water; dry it in a hot air oven overnight.
• Record the weight of the crucible.
• Ash the residue in crucible by placing it in a muffle furnace at 400º C
• Cool the crucible and record its weight.

Calculation