The Effects of Thyme and Cinnamon Essential Oils on Performance, Rumen Fermentation and Blood Metabolites in Holstein Calves Consuming High Concentrate Diet

Abstract

Essential oils have been shown to favorably effect in vitro ruminal fermentation, but there are few in vivo studies that have examined animal responses. The objective of this study was to evaluate the effects of thyme (THY) and cinnamon (CIN) essential oils on feed intake, growth performance, ruminal fermentation and blood metabolites in feedlot calves fed high-concentrate diets. Twelve growing Holstein calves (213±17 kg initial BW) were used in a completely randomized design and received their respective dietary treatments for 45 d. Treatments were: 1-control (no additive), 2-THY (5 g/d/calf) and 3-CIN (5 g/d/calf). Calves were fed ad libitum diets consisting of 15% forage and 85% concentrate, and adapted to the finishing diet by gradually increasing the concentrate ratio with feeding a series of transition diets 5 wk before the experiment started. Supplementation of THY or CIN did not affect DMI and ADG, and feed efficiency was similar between treatment groups. There were no effects of additives on ruminal pH and rumen concentrations of ammonia nitrogen and total VFA; whereas molar proportion of acetate and ratio of acetate to propionate decreased, and the molar proportion of propionate increased with THY and CIN supplementation. Rumen molar concentration of butyrate was significantly increased by adding CIN compared to control; but no change was observed with THY compared with control group. No effects of THY, or CIN were observed on valerate, isobutyrate or isovalerate proportions. Plasma concentrations of glucose, cholesterol, triglyceride, urea-N, β-hydroxybutyrate, alanine aminotransferase and aspartate aminotransferase were not changed by feeding THY or CIN. Results from this study suggest that supplementing a feedlot finishing diet with THY or CIN essential oil might be useful as ruminal fermentation modifiers in beef production systems, but has minor impacts on blood metabolites.

The effect of Mediterranean thyme (<i>Thymbra spicata</i> L. var. spicata) essential oil on fattening performance and ruminal parameters in lamb

“…In this study, the addition of TS essential oil at the levels of 10 and 15 μl per kg LW of lambs did not adversely affect LW or LW gain. The intake of concentrate feed and lucerne hay was similar which is in accordance with the results of other in vivo studies examining thyme oil and active compounds of this genus (carvacrol, thymol, γ-terpenene and p-cymene) (Bampidis et al, 2005;Chaves et al, 2008;Wang et al, 2009;Vakili et al, 2013). Simitzis et al (2008) also observed that supplementation of concentrate feed oregano essential oil (1 ml · kg −1 ) did not affect LW or LW gain.…”

“…Chaves et al (2008) found that carvacrol (purity >98%) supplementation at the level of 0.2 g · kg −1 DM reduced ruminal pH, increased VFA and did not change A:P ratio or NH 3 -N level in lambs. Besides, thyme essential oil (5 g · d −1 · calf −1 ) supplementation to growing calves diet (15% lucerne hay and 85% concentrate feed) did not affect pH value, concentration of NH 3 -N and molar concentration of VFA in rumen fluid; whereas decreased the molar proportion of acetate and A:P ratio, and increased the molar proportion of propionate (Vakili et al, 2013). In another study, addition of Origanum vulgare oil (rich in carvacrol) into lamb diet increased pH value, NH 3 -N concentration, and the molar concentration of VFA in rumen fluid (Biricik et al, 2016).…”

Effect of different dosages of oregano oil on performance and some blood parameters in lambs

“…Vakili et al (23) established that thyme essential oil in the diets of feedlot calves (5 g/day/calf) resulted in no changes in values of plasma total cholesterol and triglyceride. Whereas in another study it has been reported that, concentrations of trigycerides can be influenced by essential oil supplementation via changing of feed intake (25).…”

The effect of Mentha piperita essential oil on biochemical and haematological parameters of rams

“…This discrepancy might be explained by differences in the experimental procedure kind of animals, physiological status and various compounds used. Vakili et al (2013) reported that thyme in the diet of feedlot calves resulted in no changes in values of plasma total cholesterol and triglyceride. In the present study, WBC count was significantly higher in rams when essential oil was supplemented at the rate of 20 ml/kg.…”

“…Also, Vakili et al (2013) reported that thyme in the diet of feedlot calves resulted in no changes in plasma total cholesterol and triglyceride. Also, Vakili et al (2013) reported that thyme in the diet of feedlot calves resulted in no changes in values of plasma total cholesterol and triglyceride.…”