Determination of the Effectiveness of Microbial Inoculants in Improving the Quality of Sorghum bicolor X Sorghum sudanese Silage

Abstract

This study was conducted to determine the effects of adding five different commercial inoculants to Sorghum bicolor X Sorghum sudanese silage on silage quality, microbial development, and aerobic stability. The study consisted of a control group (SSC) and five inoculant groups (SSSILAP, SSSILAL, SSSILD, SSLAC, SSMIC), prepared in 2 kg vacuum-sealed packages with six replicates. The prepared silage samples were subjected to fermentation under laboratory conditions, and physical, chemical, microbiological, and aerobic stability analyses were performed after 90 days. Chemical analyses revealed that inoculant addition significantly reduced the pH levels of the silages (P<0.01), with the lowest pH value (4.55±0.00) observed in SSSILAL. The highest crude protein content (10.20±0.00%) was found in SSMIC, while the highest water-soluble carbohydrate (WSC) value (16.15°Brix) was recorded in SSC. Although no statistical differences were observed in color parameters among the groups, inoculant applications positively influenced color stability in terms of ΔE* and hue (h) values (P>0.05). Microbiological analyses showed the highest lactic acid bacteria population (11.00 log5 cfu/g) in SSMIC, with the lowest yeast and mold development. This supports the positive effect of inoculants on aerobic stability. In terms of nutritional value parameters, the highest digestible dry matter (60.16%) in the SSLAC group, total digestible nutrients (59.02%) in the SSMIC group, metabolic energy (2.13 Mcal/kg) in the SSK, SSSILAP and SSMIC groups and net energy for milk yield (NEL: 1.41 Mcal/kg) values ​​were obtained equally in the SSSILAL and SSMIC groups. In conclusion, inoculant applications significantly improved silage quality, enhanced fermentation efficiency by lowering pH levels, suppressed yeast and mold formation, and improved aerobic stability. SSLAC and SSMIC outperformed the others, particularly in terms of chemical composition, energy value, and microbiological quality.