Effects of carvacrol and cinnamaldehyde on microbial fermentation when added to a barley- or corn-based diet in a continuous-culture system

Abstract

. 2009. Effects of carvacrol and cinnamaldehyde on microbial fermentation when added to a barley-or corn-based diet in a continuous-culture system. Can. J. Anim. Sci. 89: 97Á104. Six dual-flow continuous-culture fermenters (1300 mL) were used to evaluate in a 2 )3 factorial arrangement the effects of carvacrol (CAR) and cinnamaldehyde (CIN) supplementation [0.2 g kg(1 of dietary dry matter (DM)] and the source of grain (barley vs. corn) on microbial fermentation. Inoculum was collected from four ruminally cannulated lactating Holstein cows fed a mixed diet of 50% forage and 50% concentrate (16.3% crude protein, 33.5% neutral detergent fiber, DM basis). The experimental period consisted of 10 d, with the first 6 d for adaptation to experimental treatments, and 4 d of sample collection. Fermenter pH was lower for corn-than for barley-based diets (6.14 vs. 6.27; P B0.05). True crude protein (CP) degradation tended (P 00.10) to be higher for barley-than for corn-based diets (47.0 vs. 41.3%). Neither CAR nor CIN altered fermentation parameters [pH, NH 3 -N, total volatile fatty acid (VFA) concentration, and molar proportions of individual VFA], nutrient digestibility, N metabolism, and efficiency of microbial protein synthesis. The results of this study show that at the dosage selected (0.2 g kg (1 of dietary DM), CAR and CIN had no effects on microbial fermentation, feed digestibility, and N metabolism in continuous-culture fermenters fed a barley-or corn-based diet.

Effects of cinnamaldehyde, eugenol, and capsicum on fermentation of a corn-based dairy ration in continuous culture

“…This is consistent with published literature (Castillejos et al 2005;Benchaar et al 2006Chaves et al 2009 Busquet et al 2005b). Although inconsistent with other literature, results from the current study suggest that the use of CIN may cause a decrease in overall nutrient digestibility, particularly in diets with ingredients processed for higher rumen fermentability; therefore, caution should be used when considering CIN as a treatment in vivo.…”

“…(1 ) in continuous culture (Chaves et al 2009; corn-and barley-based diets) elicited no change in starch digestibility. Similarly, the high dosage of 500 mg L…”

“…(1 when fed with a 50:50 forage:concentrate ratio diet, and Chaves et al (2009) reported no effects with a dosage of 3.6 mg L…”

“…The increase in isovalerate and valerate observed for CAP and CIN, respectively, also differs from the literature. There is often no effect of EO on BCVFA production (Busquet et al 2005b;Castillejos et al 2005;Fraser et al 2007;Fandin˜o et al 2008;Chaves et al 2009). However, a decrease in BCVFA has been shown when CAP (Cardozo et al 2004) and CIN (Busquet et al 2005a(Busquet et al , 2006 were supplemented in vitro, most likely due to the higher dosages used.…”

Fermentation characteristics of corn-, triticale-, and wheat-based dried distillers' grains with solubles in barley-based diets determined using continuous and batch culture systems

“…The experimental period was 8 days. Days 1–6 served as an adaptation period,16, 17 allowing for equilibration of microbial populations, followed by 2 days of sampling 16, 17…”