Effect of treatment of wheat straw with ammonia and peracetic acid on digestibility in vitro and cell wall composition

Abstract

Wheat straw was treated with four levels of ammonia (0, 35, 70 and 105 g kg −1 straw dry matter), allowed to react for five days and then treated with four levels of peracetic acid (0, 40, 80 and 120 k kg −1 straw dry matter) for five more days. There was a 1.24 percentage unit increase in dry matter digestibility in vitro (IVDMD) with each 10.0 g of ammonia added per kg of straw dry matter. The IVDMD increased 1.01 percentage unit for each 10.0 g of peracetic acid added per kg of straw dry matter. The lignin content of the straw decreased 0.39% with each 10.0 g of peracetic acid added per kg of straw dry matter. The hemicellulose content of the straw decreased 0.82% with the addition of 10.0 g of ammonia per kg of straw dry matter. Cellulose content was not affected by the addition of peracetic acid or ammonia. The development of more economical and safe procedures which combine swelling and delignification would be very beneficial for improving the nutritive value of low quality roughages.