Symposium review: Technologies for improving fiber utilization

Area of Science:

• Ruminant nutrition
• Forage science
• Agricultural biotechnology

Background:

• Lignocellulosic complex in forage limits nutrient and energy utilization by dairy cows.
• Developing technologies to enhance forage fiber utilization is crucial for improving dairy cow diets.

Purpose of the Study:

• To review and summarize various technologies aimed at increasing forage fiber utilization in dairy cows.
• To assess the efficacy, practicality, and limitations of different physical, genetic, chemical, and biological approaches.

Main Methods:

• Review of physical processing techniques (particle size reduction).
• Analysis of genetic strategies (brown midrib mutants).
• Evaluation of chemical treatments (alkalis, urea, ammonia-fiber expansion).
• Assessment of biological methods (enzymes, yeasts, fungi).

Main Results:

• Physical processing increases intake and surface area for microbial action.
• Brown midrib mutants offer repeatable improvements in fiber utilization.
• Chemical treatments like ammoniation increase digestibility and nitrogen content, but face adoption barriers.
• Biological treatments show positive overall effects, especially with synergistic agents like expansin-like proteins.
• Further research is needed for on-farm applicability and cost-effectiveness.

Conclusions:

• Multiple technologies exist to improve forage fiber utilization in dairy cows.
• Genetic and biological approaches show significant potential, with ongoing research addressing limitations.
• Optimizing these technologies is key to enhancing nutrient and energy availability from forage.