The effect of pelleting cereal straw with NaOH-addition on rumen fermentation in cows

Experiments with rumen-fistulated dairy cows were performed to study the effect of NaOH-addition to cereal pellets. Compared to straw-concentrate rations in which the straw pellets were free of NaOH, cereal straw pellets containing 2.4 kg NaOH per 100 kg straw caused the rumenal pH to go up from 6.21 to 6.47, the cellulotlytic activity to rise by some 20%, and the passage turnover rate of dry matter to increase from 0,039 to 0,056. The concentrations of volatile fatty acids and the fermentation patterns were not influenced by the NaOH-content of the pellets. It is concluded that NaOH-addition during straw pelleting has a favourable effect on digestion in the bovine rumen.