Nutritive value and aerobic stability of whole quail bush and date waste silage ensiled at different compositions and the role of hetero-fermentative lactic acid bacteria

The objective of this study was to characterize the probiotic lactic acid bacteria to improve the quality of silage. A total of 42 LAB isolates were isolated from the date syrup, and the potent strains were characterized as Lactobacillus casei LC09 and L. lactis LL25. These two strains showed the ability to survive at low pH, stimulate gastric conditions, and be sensitive to most of the prominent antibiotics. LAB strains have adhesion ability (p < 0.001) on the surface of the HT-29 cell lines and γ-hemolytic type, and no zones developed around the blood agar medium. The cell-free extract of the selected LAB showed promising DPPH and ferric reducing power activity. Among the selected fungi, LC09 showed the maximum zone of inhibition against Fusarium oxysporum (26 ± 1 mm), Aspergillus niger (27 ± 2 mm), and Fusarium graminearum (26 ± 1 mm). The strain LC09 showed maximum activity against F. graminearum (29 ± 1 mm) and F. oxysporum (24 ± 2 mm). Acetic acid and lactic acid production are the prominent end products determined from the cell free extract of both LAB (p < 0.001). Lactic acid production was 5.3 ± 0.32 g/L and 4.7 ± 0.28 g/L for strains LC09 and LL25, whereas, acetic acid level was 0.39 ± 0.03 g/L and 0.27 ± 0.47 g/L for these LAB. Quail bush and date wastes were used for the preparation of silage, and LAB strains were inoculated and treated for 30 days. In vitro silage analysis showed that quail bush-date waste inoculated with LC09 and LL25 showed a decreased pH level at the end of fermentation (after 30 days) (p < 0.001). Lactic acid and acetic acid levels were increased in the experimental silage (p < 0.001). Thus, ensiled quail bush-date waste could promote silage quality, improve fibre digestion and reduce the growth of pathogenic bacteria and fungal strains.