Improving ensiling characteristics by adding lactic acid bacteria modifies in vitro digestibility and methane production of forage-sorghum mixture silage

Abstract

Improving the nutrition of livestock is an important aspect of global food production sustainability. This study verified whether lactic acid bacteria (LAB) inoculant could promote ensiling characteristics, nutritive value, and in vitro enteric methane (CH₄) mitigation of forage sorghum (FS) mixture silage in attacking malnutrition in Zebu beef cattle. The FS at the soft dough stage, Cavalcade hay (CH), and cassava chip (CC) were obtained. The treatments were designed as a 4 × 2 factorial arrangement in a completely randomized design. Factor A was FS prepared without or with CH, CC, and CH + CC. Factor B was untreated or treated with Lactobacillus casei TH14. The results showed that all FS mixture silages preserved well with lower pH values below 4.0 and higher lactic acid contents above 56.4 g/kg dry matter (DM). Adding LAB boosted the lactic acid content of silages. After 24 h and 48 h of in vitro rumen incubation, the CC-treated silage increased in vitro DM digestibility (IVDMD) with increased total gas production and CH₄ production. The LAB-treated silage increased IVDMD but decreased CH₄ production. Thus, the addition of L. casei TH14 inoculant could improve lactic acid fermentation, in vitro digestibility, and CH₄ mitigation in the FS mixture silages.

Figure 1

The nutritive values of the tested forage sorghum (FS) mixture silages estimated to supply the maintenance requirements of Zebu beef cattle in the growth stage according to current feeding standards. CH Cavalcade hay (15% inclusion rate), CC dry cassava chip (10% inclusion rate).