Effects of Wormwood (Artemisia montana) Essential Oils on Digestibility, Fermentation Indices, and Microbial Diversity in the Rumen.

Seong Shin Lee,Hyuk Jun Lee,Sam Churl Kim,Young Ho Joo,Dong Hyeon Kim,Adegbola T Adesogan,Dimas Hand Vidya Paradhipta,Hee Yoon

doi:10.3390/microorganisms8101605

Abstract

This study investigated the effects of essential oil (EO) from three Korean wormwood (Artemisia Montana) plants on in vitro ruminal digestibility, fermentation, and microbial diversity. Dried (0.5 g) soybean meal (SBM) or bermudagrass hay (BGH) were incubated in buffered rumen fluid (40 mL) for 72 h with or without EO (5 mg/kg) from Ganghwa (GA), Injin (IN), or San (SA) wormwood (Experiment 1). Both SA and IN improved (p < 0.05) dry matter digestibility (DMD) of BGH, while GA reduced (p < 0.05) total short-chain fatty acid of BGH and SBM. Besides, SA increased (p < 0.05) numbers of Ruminococcus albus and Streptococcus bovis in SBM. Experiment 2 examined different doses (0, 0.1, 1, and 10 mg/kg) of SA, the most promising EO from Experiment 1. Applying SA at 10 mg/kg gave the highest DMD (L; p < 0.01) and neutral detergent fiber (Q; p < 0.05) digestibility for BGH. Applying SA at 1 mg/kg gave the highest R. albus population (Q; p < 0.05) in SBM. Therefore, SA was better than GA and IN at improving rumen fermentation, and the 0.1 to 1 and 10 mg/kg doses improved ruminal fermentation and in vitro digestibility of SBM and BGH, respectively.

Highlights

Interest in alternative feed additives has increased over the last few decades since many countries, including the European Union and the United States of America, imposed mandatory or voluntary restrictions on the use of antibiotics for animal production due to adverse effects on human health
Other sources of Essential oils (EO), such as oregano, thyme, and sweet orange, have been reported to have no effect on nutrient digestibility, ammonia-N, and total short-chain fatty acid (SCFA) of the rumen according to Benchaar et al [4], but they had beneficial effects on rumen fermentation according to Calsamiglia et al [1]
For the soybean meal (SBM) substrate, the application of GA resulted in lower (p = 0.026; 14.26 vs. 154.2 mM L−1) total SCFA concentration than CON, while applying IN and SA had no effect on this measure (Table 3)

Summary

Introduction

Interest in alternative feed additives has increased over the last few decades since many countries, including the European Union and the United States of America, imposed mandatory or voluntary restrictions on the use of antibiotics for animal production due to adverse effects on human health. Application of EO as feed additives has varied effects on rumen fermentation. The application of EO from lemongrass oil has improved nutrient digestibility in the rumen [3]. Other sources of EO, such as oregano, thyme, and sweet orange, have been reported to have no effect on nutrient digestibility, ammonia-N, and total short-chain fatty acid (SCFA) of the rumen according to Benchaar et al [4], but they had beneficial effects on rumen fermentation according to Calsamiglia et al [1]. The application of herbal mixtures as EO sources has improved nutrient digestibility and total SCFA concentration but is less effective at reducing methane emission [5]. The application of a mixture of medical plants (wormwood (Artemisia absinthium L.), chamomile (Matricaria chamomilla L.), fumitory (Fumaria officinalis L.), and mallow (Malva sylvestris L.)) as EO sources has decreased ammonia-N and methane concentration in vitro [6]

Methods

Results

Discussion

Conclusion