Commercial Blend Of Essential Oils Research Articles

Evaluation of the Effects of Different Natural Dietary Feed Additives on Performance and Intestinal Histomorphology in Quails

The aim of the present study was to investigate the influence of a commercial probiotic and a commercial essential oil blend and their mixture, as a natural feed additive, on growth parameters live weight (LW), live weight gain (LWG), feed intake (FI), feed conversion ratio (FCR), carcass yield (CY) and small intestinal histomorphology of quails. A total of 200 1-day-old Japanese (Coturnix coturnix japonica) quails, including both males and females, were divided into four groups containing 50 quails and treated as follows: (1) a control treatment without medication (2) 18 g ton-1 probiotic; (3) 300 g ton-1 essential oil blend and (4) 18 g ton-1 probiotic plus 300 g ton-1 essential oil blend. The results of the research show that the additives added to quail diets do not have a significant effect (P > 0.05) on the performance parameters of LW, LWG, FI and FCR. However, significant differences (P < 0.05) were found in the CY, which is one of the performance parameters. A probiotic addition of 18 g ton -1 (treatment 1) to the quail diet resulted in a significant increase (P < 0.05) in carcass yield. Moreover, the addition of natural feed additives such as probiotics, essential oil blends and mixture to quail diets caused significant (P < 0.001) increases in villus heights and crypt depth in the duodenum and ileum segments. In addition, significant (P < 0.05) enlargements were found in the villus surface area in the experimental groups compared to the control group. In conclusion, in this study, it was determined that the addition of feed additives, which are developed as an alternative to antibiotics to the quail diet did not have a negative effect on performance and caused significant differences in the effective parameters in the evaluation of intestinal health.

Synergistic effect of feed additives on cell proliferation and morphology in quail (Coturnix coturnix Japonica) duodenum

The present study aimed to investigate the effect of a commercial probiotic and a commercial essential oil blend and their mixture, as a natural feed additive, on the expression level of Proliferating Cell Nuclear Antigen (PCNA), proliferation index (PI), and total mucosal thickness of quails. 1-day-old Japanese (Coturnix coturnix japonica) quails, including both males and females, were divided into four groups as follows: (1) control treatment without medication (n: 15); (2) 18 g/ ton-1 probiotic (n: 15); (3) 300 g/ ton-1 essential oil blend (n: 15) and (4) 18 g/ ton-1 probiotic plus 300 g/ ton-1 essential oil blend (n: 15). In the study, the effect of natural feed additives added to the quail diet on intestinal health was evaluated by immunohistochemical and histological analyzes. At the end of the experiment, the quail's duodenum was removed, fixed in 10% neutral buffered formalin, and a histological examination procedure was performed.As a result of the study, it was determined that the PCNA expressions, proliferation index, and mucosal thickness were generally significantly increased in the experimental groups compared to the control group (p<0.001). The combination of additives caused a synergistic effect for this study. All data were statistically significant in the group where the probiotic and essential oil mixture was used together. It has been determined that these feed additives combination stimulates cell proliferation in the duodenum, where nutrients absorbed, and positively affect intestinal morphology.

Microbiota and Transcriptomic Effects of an Essential Oil Blend and Its Delivery Route Compared to an Antibiotic Growth Promoter in Broiler Chickens.

This study evaluated the effect of the delivery of a commercial essential oil blend containing the phytonutrients star anise, cinnamon, rosemary, and thyme oil (via different routes) on broiler chickens’ ileal and ceca microbiota and liver transcriptome compared to an antibiotic growth promoter. Eggs were incubated and allocated into three groups: non-injected, in ovo saline, and in ovo essential oil. On day 18 of incubation, 0.2 mL of essential oil in saline (dilution ratio of 2:1) or saline alone was injected into the amnion. At hatch, chicks were assigned to post-hatch treatment combinations: (A) a negative control (corn-wheat-soybean diet), (B) in-feed antibiotics, (C) in-water essential oil (250 mL/1000 L of drinking water), (D) in ovo saline, (E) in ovo essential oil, and (F) in ovo essential oil plus in-water essential oil in eight replicate cages (six birds/cage) and raised for 28 days. On days 21 and 28, one and two birds per cage were slaughtered, respectively, to collect gut content and liver tissues for further analysis. Alpha and beta diversity differed significantly between ileal and ceca samples but not between treatment groups. In-feed antibiotic treatment significantly increased the proportion of specific bacteria in the family Lachnospiraceae while reducing the proportion of bacteria in the genus Christensenellaceae in the ceca, compared to other treatments. Sex-controlled differential expression of genes related to cell signaling and tight junctions were recorded. This study provides data that could guide the use of these feed additives and a foundation for further research.

Essential Oil Delivery Route: Effect on Broiler Chicken's Growth Performance, Blood Biochemistry, Intestinal Morphology, Immune, and Antioxidant Status.

Simple SummaryMuch research is devoted to the search for potent alternatives to antibiotic growth promoters in the poultry industry. It is hypothesized that the efficacy of potential alternatives could be influenced by their type and the delivery strategy utilized. Consequently, this study evaluated the efficacy of a commercial essential oil blend across different delivery routes as a potent alternative to in-feed antibiotics in broiler chickens using selected biochemical, immune, and performance parameters. The results provide evidence that the successive delivery of essential oils via in ovo and in-water routes in broiler chickens offers the potential to improve broiler chicken biochemical and antioxidant status. However, the in ovo delivery of essential oil at 0.2 mL dosage (saline + essential oil, dilution ratio—2:1) suffers the limitations of reduced hatchability.This study evaluated the effect of an essential oil blend and its delivery routes on broiler chicken growth performance, blood biochemistry, intestinal morphology, and immune and antioxidant status. Eggs were incubated and allotted to 3 groups: non-injected group, in ovo saline group, and in ovo essential oil group. On day 18 of incubation, essential oil in saline or saline alone was injected into the amnion. At hatch, chicks were assigned to post-hatch treatment combinations (1) in ovo essential oil + in-water essential oil (in ovo + in-water EO); (2) in ovo essential oil (in ovo EO); (3) in ovo saline; (4) in-water essential oil; (5) in-feed antibiotics (Bacitracin methylene disalicylate) and (6) a negative control (NC; corn-wheat-soybean diet) in 8 replicate cages (6 birds/cage) and raised for 28 day. The in ovo EO group reduced (p < 0.05) chick length and hatchability, all groups recorded no difference in growth performance at 0–28 day. The in ovo + in-water EO treatment reduced (p < 0.05) blood creatine kinase and aspartate aminotransferase levels whilst increasing (p < 0.05) total antioxidant capacity in birds. The in ovo + in-water delivery of EO might represent a potential antibiotic reduction strategy for the poultry industry but more research is needed to address the concern of reduced hatchability.

Effect of a commercial blend of essential oils and organic acids on the performance of broiler chickens

An experiment was conducted to evaluate the effects of Bio strong Forte (BF) on the performance of broiler chickens. The BF is a commercial blend of essential oils and organic acids. Five hundred and forty (540) day old Ross broiler chicks were used in the feeding trial. The birds were randomly distributed into five treatments, each replicated thrice with 36 chicks per replicate. T1 is the control; T2, T3 and T4 had 50, 75 and 100g BF per 100kg feed, respectively while T5 had Oxytetracycline (AGP) 60g/100kg of feed. The five diets were supplied ad libitum to birds for 42 days. Parameters collected were growth performance indices, haematological parameters, liver function indices, and carcass quality. All data were subjected to analysis of variance and significant (P

Research Note: Evaluating the roles of surface sanitation and feed sequencing on mitigating Salmonella Enteritidis contamination on animal food manufacturing equipment

The objective of this study was to evaluate the efficacy of flushing surfaces with untreated feed vs. the use of 2 different dry chemical sanitizers on residual surface and feed Salmonella Enteritidis contamination. First, a Salmonella-negative batch of poultry feed was mixed in 9 laboratory-scale paddle mixers. A feed sample was collected, and targeted locations on surfaces within the mixer were swabbed to confirm Salmonella-negative. Next, a Salmonella-positive batch of poultry feed was mixed, sampled, and mixer surfaces swabbed. Mean Salmonella Enteritidis contamination across all 9 mixers were 3.63 cfu/g for sampled feed and 1.27 cfu/cm2 for surface contamination. Next, the mixers manufactured one of the following treatments (3 mixers/treatment): 1) none (control); 2) a commercially available essential oil blend; or 3) rice hulls treated with a 10% concentration of a propriety blend of medium-chain fatty acids (MCFA). After each treatment, each mixer manufactured another 2 batches of Salmonella-free feed (sequence 1 and sequence 2). Feed samples were collected, and surfaces were swabbed between each batch of feed. Manufacturing sequence (P < 0.0001) but not treatment (P > 0.05) impacted feed or surface contamination of Salmonella Enteritidis. There was Salmonella-positive residue in the batch of feed manufactured immediately after the positive control batch. However, no Salmonella residue was detected in batches of feed treated with either the commercial essential oil blend or MCFA. Low levels of Salmonella residue were observed from either feed (0.7 cfu/g for commercial essential oil blend) or surfaces (0.1 cfu/cm2 for MCFA) manufactured in sequence 1, but no residue was observed in sequence 2. These data suggest that sequencing of feed during manufacturing reduces Salmonella-positive contamination within animal food and on manufacturing surfaces, particularly after the second batch or with the use of chemical treatments.

Inclusion of a blend of copaiba, cashew nut shell and castor oil in the protein-energy supplement for grazing beef cattle improves rumen fermentation, nutrient intake and fibre digestibility

Context Essential oils are secondary plant compounds extracted from plants, with potential for the modulation of rumen fermentation. Aims Two experiments, namely one in vivo and another in vitro, were conducted to analyse the effects of a commercial blend of essential oils (EO; copaiba (Copaifera langsdorffii), cashew nut shell (Anacardium occidentale) and castor oil (Ricinus communis) and monensin as dietary feed additives in protein–energy supplements (PES) provided to grazing beef cattle, on ruminal fermentation, intake, total nutrient digestibility and protein dietary efficiency. Methods In the in vivo experiment, four entire Nellore bulls cannulated in the rumen (374 ± 15.66 kg; mean ± s.d.) were used in a 4 × 4 Latin-square design to evaluate the effects of EO concentration and monensin on voluntary intake, digestibility, and rumen and metabolic characteristics of grazing beef cattle provided with supplementation during the rainy season. Treatments were as follows: control (CON; PES without additives); monensin (MON; PES with inclusion of monensin at 20 mg/kg DM consumed); EO150 (PES with inclusion of EO at 150 mg/kg DM consumed); EO300 (PES with inclusion of EO at 300 mg/kg DM consumed). In the in vitro experiment, the effects EO150, EO300 and EO450, MON and CON on DM and neutral detergent-fibre (NDF) digestibility, and total gas production, were evaluated in four consecutive runs using a gas-production (GP) system. Key results In the in vivo experiment, DM intake, forage DM intake, crude protein intake and NDF intake were similar (P &amp;gt; 0.05) between EO150 and MON, but both were greater than those in EO300 and CON (P &amp;lt; 0.05). A lower EO concentration (EO150) increased (P &amp;lt; 0.05) NDF digestibility and improved nitrogen utilisation efficiency. In the in vitro experiment, the addition of MON and EO150 did not modify (P &amp;gt; 0.05) GP, DM and NDF digestibility compared with the control, but EO300 and EO450 decreased GP at 12 and 24 h and decreased DM and NDF digestibility at 48 h compared with the control, MON and EO150. Conclusions In vivo and in vitro results suggested that EO (copaiba oil, cashew nut shell and castor) at low doses (150 mg/kg DM) has the potential to improve ruminal fermentation in grazing beef cattle receiving supplements, but medium and high doses of EO can have adverse effects. Implications EO blends could be an alternative to MON for grazing beef cattle with access to supplements.

Feeding Essential Oils to Neonatal Holstein Dairy Calves Results in Increased Ruminal Prevotellaceae Abundance and Propionate Concentrations.

Since antibiotic use in animal production has become a public health concern, great efforts are being dedicated to find effective and viable alternatives. While essential oils (EO) have become attractive candidates for use in the livestock industry, their mode of action and microbial targets in food animals remain largely uncharacterized. To gain further insight, we investigated the rumen environment of neonatal calves fed calf starter pellets and milk replacer supplemented with a commercial blend of EO. Propionate concentrations were not only found to be higher in EO-fed calves compared to controls (P < 0.05), but ruminal bacterial communities also differed greatly. For instance, the abundance of Firmicutes was significantly lower in samples from EO-fed calves than in controls, which appeared to be mostly due to lower Lachnospiraceae levels (P < 0.05). In contrast, Bacteriodetes were more abundant in EO-fed calves compared to controls, which was primarily the result of higher Prevotellaceae (P < 0.05). Notably, two bacterial operational taxonomic units (OTUs) were significantly more abundant in EO-fed calves; SD_Bt-00966 was found to be a close relative of Prevotella ruminicola (97%), while SD_Bt-00978 likely corresponded to an uncharacterized species of Gammaproteobacteria. In addition, Pearson correlation and canonical correspondence analyses revealed potential associations between other ruminal bacterial OTUs and either short chain fatty acids (SCFA) parameters or metrics for calf growth. Together, these results support that EO supplementation in growing dairy calves can modulate rumen function through SCFA production and growth of specific rumen bacterial groups.

Effects of supplementation with L. plantarum TN8 encapsulated in alginate-chitosan in broiler chickens

This study was undertaken to investigate the effects of supplementation of probiotic strain Lactobacillus plantarum TN8 encapsulated in sodium alginate-chitosan or a commercial blend of essential oils on total cholesterol, High Density Lipoprotein (HDL), Low Density Lipoprotein (LDL) and growth performance of broiler chickens. The results showed that the broiler chickens supplemented with encapsulated L. plantarum TN8 or essential oil has a higher growth than the control group. After 35days, the weight means were 1860 and 1880g respectively in dietary supplementation with probiotic or essential oil, while they are 1800g in the control group. The evolution of the feed consumption and feed conversion per week showed that the supplementation of encapsulated TN8 strain or essential oil in broiler chickens food has a positive influence on their appetite. Similarly, supplementation of the feed with this encapsulated strain significantly reduced the rate of cholesterol (HDL and LDL) as well as the contents of triglycerides in broiler chickens. Through our study, it appears that the use of the probiotic supplementation or essential oil to broilers were found to be better than the control group of chickens, resulting in a significant economic impact and promoting effect on health.

EFFECT OF DIETARY SUPPLEMENTATION WITH AN ESSENTIAL OILS BLEND AND MANNAN OLIGOSACCHARIDE ON: 1- THE PRODUCTIVE PERFORMANCE OF GOLDEN MONTAZA LAYERS AT LATE FACE OF EGG PRODUCTION

The experimental work of the present study was carried out at El-Takamoly Poultry project (TPP), Fayoum Governorate, Egypt, during the period from March to July 2014. This study was undertaken to assess the dietary effects of essential oil blend (EOB), mannan oligosaccharides (MOS) and their combination on the productive performance of Golden Montazah laying hens at late egg production period. A total number of 720 laying hens plus 72 males of Golden Montaza at 56 weeks of age were allocated randomly into six treatments groups (120 hens plus 12 males), each group was equally subdivided into three replicates (40 hens plus four males). Birds were distributed into 18 pens (40 hens and four males each) in such order to have a similar mean body weight and average daily egg production. The dietary treatments used in this study were as follows: 1-Birds were fed the control diet (diet 1). 2- diet 1 + 200 mg prepared essential oil blend (PEO)/kg diet. 3-diet 1 + 100 mg commercial essential oil blend (CEO)/kg diet. 4-diet 1 + 500 mg MOS/kg diet. 5-diet 1+ 200 mg PEO + 500 mg MOS/kg diet. 6-diet 1 + 100 mg CEO + 500 mg MOS/kg diet. Results obtained could be summarized in the following: Laying hens fed diet containing 100 mg CEO + 500 mg MOS/kg diet had significantly higher values of egg production (EP%), live body weight change (LBWC) and the best feed conversion (FC), crude protein conversion (CPC) and caloric conversion ratio (CCR) during all significant periods studied, while, laying hens fed control diet had significantly lower values of EP%, LBWC and the worst FC, CPC and CCR during the same periods. No significant effect were observed for egg mass, feed intake, initial body weight, final body weight and mortality rate% during the experimental period. There were insignificant differences among all dietary treatments in carcass characteristics except, spleen%. Laying hens fed diet containing 100 mg CEO +500 mg MOS/kg diet had higher spleen% whereas, those fed control diet had lower spleen% at the end of experimental period. Laying hens fed diet containing 100 mg CEO + 500 mg MOS/kg diet had significantly higher values of lactic acid bacteria count and the lower values of total count of bacteria and E-coli, while, those fed control diet had significantly higher values of total count of bacteria and E-coli and the lower values of lactic acid bacteria count. Golden Montazah laying hens fed diet containing 100 mg CEO +500 mg MOS/kg diet gave the best economical and relative efficiency values during the period from 56 to 72 weeks. In conclusion, the results of this study indicated that feeding Golden Montazah laying hens on diets containing 100 mg CEO +500 mg MOS/kg diet improved the productive performance and relative economic efficiency values of laying hen during the period from 56 to 72 weeks of age.

Essential oils for dairy calves: effects on performance, scours, rumen fermentation and intestinal fauna

The first cause of death of dairy calves is often diarrhea which is mainly caused by pathogenic bacteria, which can result in excessive use of antibiotics. However, facing the increase concern by the industry and consumers, the use of antibiotics not only to control pathogens, but also to manipulate growth, has become a challenge. Alternative additives, such essential oils, have the potential to decrease antibiotic use, without reducing performance or increasing mortality of dairy calves. The objective of this study was to evaluate the use of a commercial blend of essential oils, incorporated into the calf starter and/or milk replacer to monitor the effect on overall calf performance, fecal scores and rumen fermentation parameters. A total of 30 Holstein calves received 6 l/day of a liquid diet, consisting of a commercial milk replacer containing 20% CP : 15% fat (EE). Calves had free choice access to water and calf starter. Weaning occurred at week 8, and calves were followed until the 10th week of age. Calves were assigned to one of the three treatment groups in a randomized block design. Treatments: (1) control without essential oils supplementation (C); (2) essential oils blend in the milk replacer at 400 mg/kg (MR) and (3) essential oils blend in the milk replacer (200 mg/kg) and starter feed (200 mg/kg) (MRS). From the 2nd week, calves were weighed and body measurements were taken, while concentrate intake and fecal scores were monitored daily. Blood samples were drawn weekly for determination of glucose and β-hydroxybutyrate. Fecal samples were collected weekly and analyzed for lactic acid bacteria and Enterobacteria; and ruminal fluid for determination of pH, short chain fatty acids, ammonia-N and counts of amylolytic and cellulolytic bacteria, and protozoa. Performance, fecal scores and intestines microorganisms were not affected by the essential oils supplementation. Ruminal and blood parameters were also not affected, with the exception the rumen ammonia-N concentration, with higher values when essential oils were supplemented in a combination of milk replacer and starter feed. Most of the evaluated parameters were affected by age of calves, mainly as a response to the increase in concentrate intake as animals’ aged. Essential oils are promising substitutes for antibiotics. However, the dose and routes of administration deserve further studies, allowing a better animal performance and health to be achieved.

Effects of a commercial blend of essential oils and monensin in a high-grain diet containing wheat distillers’ grains on in vitro fermentation

Li, Y. L., Li, C., Beauchemin, K. A. and Yang, W. Z. 2013. Effects of a commercial blend of essential oils and monensin in a high-grain diet containing wheat distillers’ grains on in vitro fermentation. Can. J. Anim. Sci. 93: 387–398. Our objective was to evaluate in vitro effects of a commercial blend of essential oils (BEO) versus monensin (MON) on fermentation of a high-grain diet containing wheat distillers’ dried grains with solubles (DDGS). Two experiments were conducted. The first experiment was designed as a short-term batch culture to determine the optimum dose of BEO (0, 45, 90 or 180 mg kg−1DM) on fermentation variables. The second experiment was a completely randomized block design with a 2×2 factorial arrangement of treatments using the rumen simulation technique. A high-grain dietary substrate containing wheat DDGS was supplemented with 0 or 28 mg MON kg−1DM combined with 0 and 90 mg BEO kg−1DM. Monensin did not affect the total volatile fatty acid (VFA) concentration or the molar proportions of individual VFA, but reduced CH4production (mL L−1gas; P=0.01) and disappearance of DM (P=0.04). Supplementation of BEO did not affect VFA concentration, but decreased (P=0.01) the molar proportion of acetate and reduced (P=0.02) the acetate to propionate concentration ratio and CH4production (mL g−1digested organic matter). The BEO increased (P=0.01) disappearance of neutral detergent fiber without affecting disappearance of other nutrients. These results indicate that supplementation of high-grain dietary substrate containing wheat DDGS with BEO improved fermentation pattern by increasing propionate concentration, reducing CH4production, and increasing fiber digestibility. This commercial BEO could be a potential substitute for MON for beef cattle fed high-grain diets containing DDGS.

Effects of the Essential Oil Blend CRINA® Poultry in Feed on Broiler Performance and Gut Microbiology

The aim of the present study was to investigate the influence of a commercial essential oil blend (EO), CRINA® Poultry (CRP), as an alternative to in-feed antibiotic, enramycine®, on growth parameters of broilers during pre and post-challenge with Clostridium perfringens (C. perfringens). The birds received treatments from 0 to 30 days as follows: T1, positive control (+CONT): without medication or bacterial challenge; T2, negative control (-CONT): without medication but with C. perfringens challenge; T3, antibiotic with addition of enramycin with C. perfringens challenge (ENRA); and T4, with addition of CRINA® Poultry to feed with C. perfringens challenge (CRP). Overall, feed intake (FI), body weight gain (BWG) and feed conversion ratio (FCR) was not significantly different among the four treatments (P>0.05). On the other hand, EO supplementation caused some changes in the gut morphology, birds which had received CRP had longer ileal villi as compared to +CONT or ENRA groups (P<0.05). The performance of the birds which had consumed CRP was similar to all other treatments. On the other hand, the results obtained from this trail clearly showed that CRP supplementation failed to control the proliferation of C. perfringens in the intestine. The results from this study indicated that CRP under the condition of this experiment had no influence on broilers performance but it had a positive effect on gut morphology.

Use of rosemary, oregano, and a commercial blend of essential oils in broiler chickens: In vitro antimicrobial activities and effects on growth performance1

The present study was conducted to characterize the in vitro antimicrobial activities of 3 essential oils [oregano, rosemary, and a commercial blend of essential oils (BEO)] against pathogenic and nonpathogenic bacteria and to evaluate their effects on broiler chicken performances. The chemical composition of the essential oils was determined using the gas chromatography interfaced with a mass spectroscopy. The disc diffusion method, the minimum inhibitory concentration (MIC), and the minimum bactericidal concentration (MBC) were applied for the determination of antimicrobial activities of essential oils. In vivo study, a total of seven hundred fifty 1-d-old male broiler chickens were assigned to 6 dietary treatment groups: basal diet (control; CON), CON + 44 mg of avilamycin/kg (A), CON + 100 mg of rosemary essential oil/kg (ROS), CON + 100 mg of oregano essential oil/kg (OR), CON + 50 mg of rosemary and 50 mg of oregano essential oils/kg (RO), and CON + 1,000 mg of BEO/kg (essential oil mixture, EOM). The essential oils isolated from rosemary and oregano were characterized by their greater content of 1,8-cineole (49.99%) and carvacrol (69.55%), respectively. The BEO was mainly represented by the aldehyde (cinnamaldehyde) and the monoterpene (1,8-cineole) chemical groups. The results of the disc diffusion method indicated that the rosemary essential oil had antibacterial activity (P ≤ 0.05) against only 3 pathogenic bacteria, Escherichia coli (8 mm), Salmonella indiana (11 mm), and Listeria innocua (9 mm). The essential oil of oregano had antimicrobial activities (P ≤ 0.05) on the same bacteria as rosemary but also on Staphylococcus aureus (22 mm) and Bacillus subtilis (12 mm). Oregano essential oil had greater (P ≤ 0.05) antimicrobial activities against pathogenic bacteria than rosemary essential oil but they had no synergism between them. The BEO showed an increased antimicrobial activity (P ≤ 0.05) against all studied bacteria (pathogenic and nonpathogenic bacteria) except for Lactobacillus rhamnosus. The supplementation of the basal diet with avilamycin or essential oils improved (P ≤ 0.05) broiler chicken BW, BW gain, and G:F compared with the CON diet. There were no differences in growth performances among birds fed A, ROS, OR, RO, or EOM diets. In general, essential oils contained in rosemary, oregano, and BEO can substitute for growth promoter antibiotics. Although the 3 essential oils had different antimicrobial activities, they exhibited the same efficiency in broiler chickens.

Protective essential oil attenuates influenza virus infection: An in vitro study in MDCK cells

BackgroundInfluenza is a significant cause of morbidity and mortality. The recent pandemic of a novel H1N1 influenza virus has stressed the importance of the search for effective treatments for this disease. Essential oils from aromatic plants have been used for a wide variety of applications, such as personal hygiene, therapeutic massage and even medical practice. In this paper, we investigate the potential role of an essential oil in antiviral activity.MethodsWe studied a commercial essential oil blend, On Guard™, and evaluated its ability in modulating influenza virus, A/PR8/34 (PR8), infection in Madin-Darby canine kidney (MDCK) cells. Influenza virus was first incubated with the essential oil and infectivity in MDCK cells was quantified by fluorescent focus assay (FFA). In order to determine the mechanism of effects of essential oil in viral infection inhibition, we measured hemagglutination (HA) activity, binding and internalization of untreated and oil-treated virus in MDCK cells by flow cytometry and immunofluorescence microscopy. In addition, the effect of oil treatment on viral transcription and translation were assayed by relative end-point RT-PCR and western blot analysis.ResultsInfluenza virus infectivity was suppressed by essential oil treatment in a dose-dependent manner; the number of nascent viral particles released from MDCK cells was reduced by 90% and by 40% when virus was treated with 1:4,000 and 1:6,000 dilutions of the oil, respectively. Oil treatment of the virus also decreased direct infection of the cells as the number of infected MDCK cells decreased by 90% and 45% when virus was treated with 1:2,000 and 1:3,000 dilutions of the oil, respectively. This was not due to a decrease in HA activity, as HA was preserved despite oil treatment. In addition, oil treatment did not affect virus binding or internalization in MDCK cells. These effects did not appear to be due to cytotoxicity of the oil as MDCK cell viability was only seen with concentrations of oil that were 2 to 6 times greater than the doses that inhibited viral infectivity. RT-PCR and western blotting demonstrated that oil treatment of the virus inhibited viral NP and NS1 protein, but not mRNA expression.ConclusionsAn essential oil blend significantly attenuates influenza virus PR8 infectivity in vitro without affecting viral binding or cellular internalization in MDCK cells. Oil treated virus continued to express viral mRNAs but had minimal expression of viral proteins, suggesting that the antiviral effect may be due to inhibition of viral protein translation.

The effect of feeding a commercial essential oil product on Clostridium perfringens numbers in the intestine of broiler chickens measured by real-time PCR targeting the α-toxin-encoding gene ( plc)

Proliferation of Clostridium perfringens type A in the broiler intestinal tract is related to poor growth and litter quality, and can under certain conditions lead to the development of necrotic enteritis (NE), a severe gastrointestinal disease in broilers. The aim of the present study was to investigate the influence of a commercial essential oil blend, CRINA ® Poultry, on the intestinal C. perfringens population in broilers vaccinated against coccidiosis. The observed C. perfringens levels were relatively high in general and peaked at 27 days of bird age with numbers ranging from 7 to 8 log cells per g of ileal and caecal content; these numbers correspond to those typically found in birds suffering from NE. No C. perfringens-related pathological changes were observed, however, indicating low levels of virulent strains among the C. perfringens or lack of other predisposing factors. Dietary concentrations of 100 and 200 mg/kg feed of the essential oil blend did not reduce the intestinal numbers of C. perfringens compared to a non-supplemented control group ( P>0.05). Further, the essential oil blend failed to improve ( P>0.05) both the growth and feed conversion ratio of the broilers. For rapid quantification of C. perfringens type A in broilers, a real-time PCR assay, targeting the α-toxin-encoding plc gene, was developed for use in ileal and caecal samples and was shown to be a fast and reliable alternative to conventional plate counting.

Antimicrobial properties of plant secondary metabolites

Increasing awareness of hazards associated with the use of antibiotic and chemical feed additives has accelerated investigations into plants and their extracts as feed additives. The present review mainly discusses two classes of plant secondary compounds in this context, i.e. essential oils and saponins. The broader potential of plants and their extracts is illustrated by the progress of an EC Framework 5 project, 'Rumen-up'. Dietary inclusion of a commercial blend of essential oils causes markedly decreased NH3 production from amino acids in rumen fluid taken from sheep and cattle. This effect is mediated partly by the effects on hyper-NH3-producing bacteria and the protein- and starch-fermenting rumen bacterium, Ruminobacter amylophilus. Saponin-containing plants and their extracts suppress the bacteriolytic activity of rumen ciliate protozoa and thereby enhance total microbial protein flow from the rumen. The effects of some saponins are transient, because saponins are hydrolysed by bacteria to their corresponding sapogenin aglycones, which are much less toxic to protozoa. Saponins also have selective antibacterial effects that may prove useful in, for example, controlling starch digestion. The 'Rumen-up' project began with a targetted collection of European plants and their extracts, which partners have tested for their effects on rumen proteolysis, protozoa, methanogenesis and lactate production. A success rate of about 5% in terms of positive hits illustrates that plant secondary compounds, of which essential oils and saponins comprise a small proportion, have great potential as 'natural' manipulators of rumen fermentation to benefit the farmer and the environment in the future.

Cinnamaldehyde, but Not Thymol, Counteracts the Carboxymethyl Cellulose-induced Growth Depression in Female Broiler Chickens

The question addressed was whether dietary essential oils could antagonize the negative effect of Carboxymethyl cellulose (CMC) on growth performance in broilers. Diets without or with 1% CMC, and CMC containing diet with either 100 ppm thymol, cinnamaldehyde or a commercial essential oil blend were fed to female broiler chickens for 40 days. Chicks receiving the CMC diet showed significantly depressed weight gain for the period of 0 - 21 days. Addition of cinnamaldehyde or commercial essential oil to the CMC diet partially counteracted the negative effect on growth performance. Group mean feed intake was lower in CMC-fed chicks, but was raised when cinnamaldehyde or the commercial oil was added to the diet. Intestinal viscosity was increased by CMC inclusion, but was not lowered by the additives. Fat digestibility was significantly reduced by CMC, but cinnamaldehyde or commercial oil inclusion partially reversed this effect. This study indicates that cinnamaldehyde, but not thymol, may antagonize the negative effects of CMC on growth performance which may relate to improving fat digestibility.