Quality and microbial community analysis of solid-state fermented feed with mixed bacteria from corn silage

Area of Science:

• Animal Science
• Microbiology
• Agricultural Science

Background:

• The efficacy of fermented feeds (FF) relies on microbial composition, necessitating cost-effective, local formulations for sustainable livestock production.
• Corn silage bacteria (CSB) present a potential source for developing solid-state fermented feed (SFF) formulations.
• Comparison with purchased marketed bacteria (PMB) is crucial for validating local microbial applications.

Purpose of the Study:

• To evaluate the efficacy of CSB for preparing SFF for pigs.
• To compare the microbial composition and fermentation characteristics of CSB-based SFF with PMB-based SFF and unfermented feed (CK).
• To investigate the potential of CSB in SFF to improve nutrient utilization in pigs.

Main Methods:

• Anaerobic fermentation of conventional feed using 5% CSB, PMB, or saline (control) at 37°C for 5 days.
• High-throughput sequencing to analyze microbial community composition and diversity at days 0, 3, and 5.
• Determination of pH, titratable acidity (TA), crude fiber, and crude fat content before and after fermentation.

Main Results:

• CSB fermentation resulted in dominant genera of *Weissella*, while PMB fermentation showed dominant genera of *Bacteroidetes*.
• Both CSB and PMB SFF exhibited decreased pH and increased TA compared to CK during fermentation.
• SFF supplemented with CSB and PMB had higher crude fiber and lower crude fat content than CK.

Conclusions:

• Corn silage bacteria (CSB) are suitable for fermenting porcine solid feeds, yielding SFF with distinct microbial profiles.
• CSB-based SFF fermentation leads to changes in pH, acidity, and nutrient composition, comparable to PMB-based SFF.
• The microorganisms in CSB-fermented feed show potential for enhancing intestinal absorption of complex polysaccharides in pigs, providing a theoretical basis for its application.