Nitrogen utilization and ruminal fermentation in steers fed soybean meal treated with formaldehyde

Area of Science:

• Animal Nutrition
• Ruminant Physiology
• Biochemistry

Background:

• Soybean meal (SBM) is a key protein source for ruminants.
• Optimizing nitrogen (N) utilization is crucial for animal productivity and environmental sustainability.
• Formaldehyde treatment is explored to alter protein digestion and absorption.

Purpose of the Study:

• To investigate the effects of formaldehyde treatment of SBM on nitrogen utilization and ruminal fermentation in steers.
• To determine the optimal level of formaldehyde treatment for improved N retention.
• To assess the impact on nutrient digestibility and ruminal parameters.

Main Methods:

• Four rumen-fistulated steers were used in a 4x4 Latin square design.
• Diets contained SBM treated with 0, 0.3, 0.6, or 0.9% formaldehyde.
• Measurements included N digestibility, N excretion, N retention, ruminal fermentation, and plasma metabolites.

Main Results:

• Formaldehyde treatment linearly decreased N digestibility and urinary N excretion.
• A quadratic increase in N retention was observed with increasing formaldehyde levels.
• Ruminal ammonia-N decreased, while plasma urea-N decreased and plasma amino acids increased.
• Ruminal N disappearance from SBM was significantly reduced by formaldehyde treatment.

Conclusions:

• Formaldehyde treatment of SBM enhances nitrogen retention in steers, primarily by reducing N excretion.
• Low levels of formaldehyde (0.3%) minimally affect nutrient digestibility and ruminal fermentation.
• Formaldehyde treatment alters ruminal fermentation patterns and improves amino acid availability.