Effects of Four Essential Oils on Nutrients Digestibility of In Vitro Ruminal Fermentation

Abstract

This research was done to study the effect of four essential oils (EOs), as feed additives, on ruminal nutrient digestibility in order to find out candidate of rumen modifier. Those four EOs were destilated from Foeniculum vulgare (Mill), Pinus merkusii (Jungh. & de Vriese), Cymbopogon nardus (L.) Rendle and Melaleuca leucadendra (L.). Their effect on dry matter (DM), organic matter (OM), crude protein (CP) and crude fiber (CF) digestibility were studied using in vitro rumen fermentation technique according to Theodorou method. Data were statistically analysed using analysis of variance factorial 4x5 design. Feed for fermentation substrate consist of Pennisetum purpureum, rice bran and wheat pollard. Essential oil individually was added and mix with substrate to meet the final concentration in fermentation media of 0, 100, 200, 400 and 800 mg/l. P. merkusii, C. nardus and M. leucadendra EOs reduced DM, OM, and CF digestibilities. The decreasing were in line with the increasing of EOs doses. Therefore F. vulgare only reduced CF digestibility. The value of DM, OM and CP digestibilities in fermentation with F. vulgare did not differ from control. CP digestibility differed among EO treatments. In F. vulgare, and P. merkusii, treatments, CP digestibility did not differ from control, whereas overall CP digestibility in C. nardus tended to be higher than control and CP digestibility in M. leucadendra was significantly higher. All EOs addition reduced CF digestibility at all level. CF digestibility in fermentation added 800 mg/l of M. leucadendra EO was slumped to only 14.29% of control. Among four EOs M. leucadendra is the most potent on interrupt rumen feed fermentation whereas P. merkusii and C. nardus in moderate ways and F. vulgare in delicate manner.

Effects of Essential Oil Blends on In Vitro Apparent and Truly Degradable Dry Matter, Efficiency of Microbial Production, Total Short-Chain Fatty Acids and Greenhouse Gas Emissions of Two Dairy Cow Diets

“…Consistent with our result on the effect of the EOBs on the HC diet, [ 18 ] reported a decrease in DM digestibility when thymol was supplemented at 500 mg/L in a dual-flow continuous culture system. Several other studies (both in vivo and in vitro studies) have reported similar depression in DM digestibility with inclusion of EOs and their mixtures [ 17 , 19 , 20 ].…”

“…The observed decrease in IVDDM in the present with the inclusion of EOBs was expected as lipids tend to reduce DM digestibility. The decline in digestibility with the inclusion of EOBs could also be associated with a reduction in protozoa population that help to engulf starch in the rumen [ 17 ]. A reduction in the protozoa population also has additional advantages as they are mainly responsible for CH 4 production.…”

Strategy to Reduce Methane to Increase Feed Efficiency in Ruminants Through Adding Essential Oils as Feed Additives

“…This study's pH value is within the range of values necessary for optimal rumen microbial activity. In a previous study, an increased essential oil supplementation did not affect pH (Gunal et al 2013;Kurniawati et al 2018).…”

Essential Oils in Nellore Beef Cattle: In Vivo Impact on Rumen Emissions

“…Our study found that EO inclusion at 3 mg/day did not affect the apparent digestibility coefficients of DM, NDF, or ADF, aligning with results from Lin et al [ 32 ], Benchaar et al [ 33 ] and Meyer et al [ 29 ], who also reported no significant changes with various EO treatments. Nonetheless, studies such as those by Kurniawati et al [ 34 ] and Metwally [ 35 ] have shown that EOs can either decrease or enhance digestibility based on the EO type and dosage, underscoring the complexity and context-dependency of EO effects.…”