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

Area of Science:

• Animal Nutrition
• Ruminant Physiology
• Feed Science

Background:

• Wheat is a key ruminant feed, but its starch can be rapidly degraded in the rumen.
• Rumen fermentation parameters and starch degradation influence nutrient availability and animal performance.
• Developing effective methods to modify wheat starch for improved postruminal digestion is crucial.

Purpose of the Study:

• To evaluate the impact of sodium hydroxide (NaOH) and formaldehyde treatment on wheat.
• To assess the effects on rumen fermentation, including pH, short-chain fatty acid (SCFA) production, and microbial activity.
• To determine the influence on ruminal and postruminal starch degradation and subsequent glucose supply in steers.

Main Methods:

• Holstein steers fitted with rumen, duodenal, and ileocecal cannulas were fed diets containing 2 kg/day of untreated, NaOH-treated (2% as-fed basis), or formaldehyde-treated (2% crude protein basis) wheat.
• Rumen fermentation parameters (pH, SCFA, microbial activity) were monitored.
• In vivo starch degradation and duodenal starch flow were quantified.

Main Results:

• Neither NaOH nor formaldehyde treatment negatively impacted key rumen fermentation parameters (pH, SCFA, microbial activity).
• Dietary inclusion of NaOH-treated wheat significantly improved fiber degradation within the rumen.
• Feeding both NaOH- and formaldehyde-treated wheat significantly increased the quantity of starch reaching the small intestine (duodenum) by 57% and 75%, respectively, compared to controls.

Conclusions:

• Wheat treatment with NaOH or formaldehyde effectively increases the amount of starch available for digestion in the small intestine.
• These treatments enhance starch utilization, leading to a greater glucose supply for ruminant animals.
• The treatments did not compromise essential rumen functions, indicating a viable strategy for improving feed efficiency.