Rumen fermentation and starch degradation by Holstein steers fed sodium-hydroxide- or formaldehyde-treated wheat

The authors investigated the effect of feeding 2% sodium-hydroxide-treated (as-fed basis) or 2% formaldehyde-treated (crude protein basis) wheat to rumen-, duodenal- and ileocaecal-cannulated Holstein steers on rumen fermentation and ruminal and postruminal starch degradation. Feeding 2 kg/day wheat treated with sodium hydroxide (NaOH) or formaldehyde did not affect negatively the main parameters of rumen fermentation, i.e. pH, short-chain fatty acid (SCFA) production, and microbial activity. Fibre degradation in the rumen was significantly improved when NaOH-treated wheat was fed. The in vivo experiments demonstrated that feeding NaOH- and formaldehyde-treated wheat to steers significantly increased the amount of starch that reached the small intestine. The amount of starch that entered the duodenum increased by 57% and 75% when steers were fed NaOH- and formaldehyde-treated wheat compared to the control phase, respectively. This higher quantity of starch was digested and absorbed, which can provide an increased glucose supply to the animals.