Impacts of Partially Substituting Concentrates With Wet Raw or Probiotic Fermented Baijiu Sorghum Distiller's Grains on In Vitro Ruminal Fermentation and Growth Performance of Beef Cattle

This study examined effects of sorghum distiller's grains (SDG) processing types (wet raw [RSDG], probiotic fermented for 0
[SDGF0] and 60 days [SDGF60]) and replacement levels for concentrate (0%, 12.5%, and 25%) on in vitro nutrient degradability,
gas production, and ruminal fermentation. Furthermore, an in vivo experiment was conducted to evaluate effects of SDGF60
substitution levels on growth performance of beef cattle. The in vitro dry matter (DM) and crude protein (CP) degradability at
72 h for RSDG and SDGF0 diets decreased with SDG substitution level increasing from 0% to 25%. Meanwhile, 12.5% substitution
level for SDGF60 exhibited higher fiber degradability than 0% and 25% levels. Theoretical maximum of gas production (A)
was affected by diet treatment, and 25% SDG level had lower A than 0% and 12.5% levels. Except NH3-N
concentration, rumen
fermentation parameters were unaffected by substitution levels and SDG processing types. The DM degradability at 72 h and
comprehensive evaluation score for 12.5% SDGF60 and control diets were above average. Compared to 0% level, 12.5% SDGF60
sustained similar DM intake and average daily gain (ADG), and marginally improved feed to gain ratio (F/G) and net profit.
Hence, 12.5% SDGF60 as a substitute for concentrate was recommended for beef cattle farming.