Effects of concentrated separator by-product (desugared molasses) on intake, site of digestion, microbial efficiency, and nitrogen balance in ruminants fed forage-based diets1

Application of condensed molasses fermentation solubles and lactic acid bacteria in corn silage production

BACKGROUND

The aim of this study is to investigate the application of two lactic acid bacteria and dry condensed molasses fermentation solubles (CMS) in the making and preservation of corn silage. Forage corn materials are divided into eight treatment groups as follows: (i) control, (ii) B2 (Lactobacillus plantarum B2, 1 × 10⁹ cfu kg^-1 ), (iii) LAS (Lactobacillus buchneri 40788, 3 × 10⁸ cfu kg^-1 ), (iv) B2 + LAS, (v) CMS (35 g kg^-1 , fresh weight), (vi) B2 + CMS, (vii) LAS + CMS and (viii) B2 + LAS + CMS. The silage composition and aerobic stability are determined after ensiling for 90 days. Furthermore, the digestibility of the silage product and gas production are evaluated using a trotro digestion procedure.

RESULTS

The assay results indicate that the CMS supplementation and B2 inoculation significantly increased lactic acid concentration (P < 0.01). However, they also reduced the content of acetic acid and silage pH at the initial fermentation stage. The CMS supplemented with B2 (B2 + CMS) showed an improvement in the quality of silage, but a significant decrease in aerobic stability (P < 0.01). The B2 + LAS + CMS treatment yielded an increase in acetic acid production during the late fermentation period and is able to extend the aerobic stability of corn silage. Furthermore, this study shows that CMS supplementation alone can significantly improve the digestibility of the in vitro dry matter (P < 0.01) and the microbial protein synthesis efficiency (P = 0.01). In addition, the CMS supplementation is beneficial for enhancing the aerobic stability of corn silage.

CONCLUSIONS

These results suggest that the combination of CMS supplementation and a suitable inoculation lactic acid bacterial strain can be highly promising for enhancing the higher quality and stability of corn silage. © 2020 Society of Chemical Industry.

Effects of concentrated separator by-product (desugared molasses) on intake, ruminal fermentation, digestion, and microbial efficiency in beef steers fed grass hay

Concentrated separator by-product (CSB) is produced when beet molasses goes through an industrial desugaring process. To investigate the nutritional value of CSB as a supplement for grass hay diets (12.5% CP; DM basis), 4 ruminally and duodenally cannulated beef steers (332 +/- 2.3 kg) were used in a 4 x 4 Latin square with a 2 x 2 factorial arrangement of treatments. Factors were intake level: ad libitum (AL) vs. restricted (RE; 1.25% of BW, DM basis) and dietary CSB addition (0 vs. 10%; DM basis). Experimental periods were 21 d in length, with the last 7 d used for collections. By design, intakes of both DM and OM (g/kg of BW) were greater (P < 0.01; 18.8 vs. 13.1 +/- 0.69 and 16.8 vs. 11.7 +/- 0.62, respectively) for animals consuming AL compared with RE diets. Main effect means for intake were not affected by CSB (P = 0.59). However, within AL-fed steers, CSB tended (P = 0.12) to improve DMI (6,018 vs. 6,585 +/- 185 g for 0 and 10% CSB, respectively). Feeding CSB resulted in similar total tract DM and OM digestion compared with controls (P = 0.50 and 0.87, respectively). There were no effects of CSB on apparent total tract NDF (P = 0.27) or ADF (P = 0.35) digestion; however, apparent N absorption increased (P = 0.10) with CSB addition. Total tract NDF, ADF, or N digestion coefficients were not different between AL- and RE-fed steers. Nitrogen intake (P = 0.02), total duodenal N flow (P = 0.02), and feed N escaping to the small intestine (P = 0.02) were increased with CSB addition. Microbial efficiency was unaffected by treatment (P = 0.17). Supplementation with CSB increased the rate of DM disappearance (P = 0.001; 4.9 vs. 6.9 +/- 0.33 %/h). Restricted intake increased the rate of in situ DM disappearance (P = 0.03; 6.4 vs. 5.3 +/- 0.33 %/h) compared with AL-fed steers. Ruminal DM fill was greater (P = 0.01) in AL compared with RE. Total VFA concentrations were greater (P = 0.04) for CSB compared with controls; however, ammonia concentrations were reduced (P = 0.03) with CSB addition. At different levels of dietary intake, supplementing medium-quality forage with 10% CSB increased N intake, small intestinal protein supply, and total ruminal VFA.