Effects of Adding Pre-Fermented Fluid Prepared from Red Clover or Lucerne on Fermentation Quality and In Vitro Digestibility of Red Clover and Lucerne Silages

Abstract

This study examined the effects of chopping or chopping + blender maceration of red clover or lucerne on pre-fermented juice (PFJ) and determined the effects of PFJs on the quality of red clover silage or lucerne silage. The PFJs from chopping red clover (PFJ-RC) or lucerne (PFJ-LC) had a higher lactic acid bacteria (LAB) count than that from chopping + blender maceration (p < 0.05) and were used as additives. Compared with the Control of both silages, adding PFJ increased LAB, lactic acid (LA), and in vitro digestibility of dry matter (IVDMD) (p < 0.05), while pH, acetic acid (AA), and ammonia nitrogen/total nitrogen (NH3-N/TN) were decreased (p < 0.05). For red clover silages, the PFJ-RC treatment contained the greatest LAB and LA and the lowest pH and NH3-N/TN among treatments (p < 0.05); similar results were observed in PFJ-LC treatment for lucerne silages (p < 0.05). The IVDMD of both silages correlated negatively with pH, AA, and NH3-N/TN and positively with LA (p < 0.05). Overall, chopping alone was a better method for preparing PFJ. Adding PFJ at ensiling increased LA and decreased the pH, AA, and NH3-N/TN of both silages. Ensiling lucerne or red clover with PFJ from the ensiling material had a more positive effect on the fermentation parameters mentioned above. Satisfactory fermentation parameters detected in the present study contributed to improving the IVDMD of both silages.

The Potential of Pre-fermented Juice or Lactobacillus Inoculants to Improve the Fermentation Quality of Mixed Silage of Agro-Residue and Lucerne

“…The LAB count and pH in pre-fermented juice before ensiling were 7.61 log cfu/ml and 4.16, consistent with the previous studies ( Sun et al, 2021 ). When 80% lucerne was mixed with RS and WB, the adjusted DM content was > 360 g/kg, which met requirements for ideal DM (range of 300–400 g/kg for quality silage; McDonald et al, 1991 ).…”

“…Furthermore, inoculation with pre-fermented juice decreased silage AN concentration over the entire ensiling interval. Similar to that of Sun et al (2021) , who added pre-fermented juice to lucerne silage and found that pre-fermented juice efficacity decreased pH and AN and increased LA content. The possible reason was as follows: first, exogenous microbiota prepared from epiphytic LAB of lucerne were more likely to adapt and reconstitute in lucerne compared to LAB derived from other crops during ensiling; second, inoculation with pre-fermented juice could stimulate LAB to use fermentable substances at the onset of ensiling ( Ohshima, 1997 ; Shao et al, 2007 ).…”

“…However, in this study four species ( W. cibaria , L. brevis , L. plantarum , and L. paralimentarius ) of LAB in three genera were present in pre-fermented juice, with W. cibaria (96.9%) being dominant. Sun et al (2021) also found that W. cibaria was identified in the pre-fermented juice prepared from lucerne. Preparation of pre-fermented juice involved culturing microbes on the crop surface.…”

“…There were greater abundances of Lactobacillus , Weissella , and Pediococcus in J and LPB silages at Days 5 and 15 of ensiling, which may have promoted rapid and efficient LA fermentation and faster pH reduction early in ensiling. Similarly, silages treated with pre-fermented juice had higher LAB counts and LA contents, but lower pH than untreated lucerne silage ( Sun et al, 2021 ). In the current study, L. nodensis and L. parabrevis were the predominant bacteria in all groups on Days 5 and 15 of ensiling.…”

“… Tao et al (2018) observed the Lactobacillus and Pediococcus in pre-fermented juice prepared from lucerne using agar media-based culturing method, while seven common LAB species were identified in lucerne pre-fermented juice using 16S rRNA gene sequencing techniques ( Sun et al, 2021 ). However, in this study four species ( W. cibaria , L. brevis , L. plantarum , and L. paralimentarius ) of LAB in three genera were present in pre-fermented juice, with W. cibaria (96.9%) being dominant.…”