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1.
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.  相似文献   

2.
The repellent effects of the essential oil of Lavendula angustifolia on adults of Hyalomma marginatum rufipes was studied at concentrations of 5, 10 and 20% v/v. A suitable tick climbing bioassay based on the questing behaviour of ticks was used to test for repellency. High percentage repellency (range 70-100) was shown at all concentrations of the essential oil of L. angustifolia, although at 5% v/v it only persisted for the first 40 minutes compared with 120 minutes at other concentrations (10 and 20% v/v). The repellent strength of L. angustifolia compared well (P > 0.05) with that of DEET (N,N-diethyl-m-toluamide), a commercial reference repellent, for the 2-hour period of the study.  相似文献   

3.
Managing the poultry red mite, Dermanyssus gallinae (De Geer) by conventional means (i.e., synthetic acaricides) has become increasingly problematic. As a possible alternative, research has identified several plant essential oils that are toxic to D. gallinae. However, essential oils are highly volatile and any acaricidal effect they exert could be short-lived in practice.This study investigated the short-lived toxicity of six lavender essential oils to D. gallinae. In sealed Petri-dishes, mites were exposed to filter papers impregnated with essential oil at a concentration of 0.14 mg/cm3. When filter papers were used immediately after impregnation, 66–90% D. gallinae mortality was observed after 24 h, depending upon the essential oil used. If impregnated filter papers were left in a fume cupboard for 24 h prior to use, mortality rates of D.gallinae fell to 11% or less.  相似文献   

4.
This study was performed to assess the in vivo ocular toxicity of benzalkonium chloride (BAK) homologs compared with commercially available BAK (BAK mixture) and to assess the ocular toxicity of BAK homolog after repeated ocular application. Rabbit eyes were examined by ophthalmology and scanning electron microscopy (SEM) after 10 applications of BAK homologs with C12 (C12-BAK) and C14 (C14-BAK) alkyl chain lengths and a BAK mixture at concentrations of 0.001% (w/v), 0.003% (w/v), 0.005% (w/v), 0.01% (w/v) and 0.03% (w/v). The ocular toxicity of C12-BAK to rabbit eyes was examined by ophthalmology and histopathology after repeated ocular application for 39 weeks. In addition, the antimicrobial activities of C12-BAK and C14-BAK against A. niger, S. aureus and P. aeruginosa were assessed. Ocular toxicity of C12-BAK was less than those of the BAK mixture and C14-BAK. No ocular toxicity was noted after ocular application of 0.01% C12-BAK to rabbits for 39 weeks. C12-BAK showed antimicrobial activities at a concentration of 0.003%. These results suggest that the use of C12-BAK to replace BAK mixture as a preservative in ophthalmic solutions should be considered in order to reduce the incidence of the corneal epithelial cell injury induced clinically by BAK.  相似文献   

5.
Anthelmintic resistance is a worldwide concern in small ruminant industry and new plant-derived compounds are being studied for their potential use against gastrointestinal nematodes. Mentha piperita, Cymbopogon martinii and Cymbopogon schoenanthus essential oils were evaluated against developmental stages of trichostrongylids from sheep naturally infected (95% Haemonchus contortus and 5% Trichostrogylus spp.) through the egg hatch assay (EHA), larval development assay (LDA), larval feeding inhibition assay (LFIA), and the larval exsheathment assay (LEA). The major constituent of the essential oils, quantified by gas chromatography for M. piperita oil was menthol (42.5%), while for C. martinii and C. schoenanthus the main component was geraniol (81.4% and 62.5%, respectively). In all in vitro tests C. schoenanthus essential oil had the best activity against ovine trichostrongylids followed by C. martini, while M. piperita presented the least activity. Cymbopogon schoenanthus essential oil had LC(50) value of 0.045 mg/ml in EHA, 0.063 mg/ml in LDA, 0.009 mg/ml in LFIA, and 24.66 mg/ml in LEA. The anthelmintic activity of essential oils followed the same pattern in all in vitro tests, suggesting C. schoenanthus essential oil could be an interesting candidate for nematode control, although in vivo studies are necessary to validate the anthelmintic properties of this oil.  相似文献   

6.
Managing the poultry red mite, Dermanyssus gallinae (De Geer) by conventional means (i.e., synthetic acaricides) has become increasingly problematic. As a possible alternative, research has identified several plant essential oils that are toxic to D. gallinae. However, essential oils are highly volatile and any acaricidal effect they exert could be short-lived in practice.This study investigated the short-lived toxicity of six lavender essential oils to D. gallinae. In sealed Petri-dishes, mites were exposed to filter papers impregnated with essential oil at a concentration of 0.14 mg/cm3. When filter papers were used immediately after impregnation, 66–90% D. gallinae mortality was observed after 24 h, depending upon the essential oil used. If impregnated filter papers were left in a fume cupboard for 24 h prior to use, mortality rates of D. gallinae fell to 11% or less.  相似文献   

7.
开发新的抗螨药物势在必行,而香精油及其组分具有显著的抑螨效果。百里酚(香精油的一种主要组分)及其一些组分,在实验室试验中其杀螨率一般都超过90%,而且对蜜蜂危害小,长期使用后在蜂蜜中的残留量很低,但要应用于养蜂生产,还有许多工作要做。对香精油在蜂群抗螨中的应用情况进行了综述。  相似文献   

8.
Pentzia incana is one of the most important of all natural pasture plants in the dry interior (Karoo) region of South Africa. This highly aromatic shrub is thought to be responsible for the distinctive flavour of Karoo lamb (a registered geographical indication), yet the essential oil is here characterised for the first time. Leafy twigs are traditionally chewed for relief of stomach ache. Essential oil is associated with numerous small, multicellu- lar glands. Gas chromatography and gas chromatography/mass spectrometry analysis of 17 essential oil samples from five populations showed considerable variation in both yield (0.12% to 0.88% dry weight) and composition. Of interest was the presence of one major biosynthetic group comprising yomogi alcohol (to 38.9%), artemisia alcohol (to 26.1%), artemisia ketone (to 35.0%) and artemisyl acetate (to 9.4%). High levels of fragranol (26.9%) and fragranyl acetate (27.1%) were observed only in a single specimen. Other main compounds were 1,8-cineole (to 16.7%), santolina alcohol (to 11.3%), camphor (to 47.9%), linalyl acetate (to 17.4%) and bicyclogermacrene (to 11.8%). Six of the 10 major compounds were isolated and their identities confirmed by nuclear magnetic resonance. The volatile compounds may possibly be linked to the medicinal use of P. incana, as well as the flavour profile of Karoo lamb.  相似文献   

9.
The aim of this study was to evaluate the antimicrobial activity and determine the minimum bactericidal concentration (MBC) of the essential oils derived from Origanum vulgare (oregano), Melaleuca alternifolia (tea tree), Cinnamomum cassia (cassia), and Thymus vulgaris (white thyme) against Salmonella Typhimurium, Salmonella Enteritidis, Escherichia coli, Staphylococcus aureus and Enterococcus faecalis. The study also investigated the ability of these different bacterial strains to develop adaptation after repetitive exposure to sub-lethal concentrations of these essential oils. The MBC of the essential oils studied was determined by disc diffusion and broth dilution methods. All essential oils showed antimicrobial effect against all bacterial strains. In general, the development of adaptation varied according to the bacterial strain and the essential oil (tea tree > white thyme > oregano). Therefore, it is important to use essential oils at efficient bactericidal doses in animal feed, food, and sanitizers, since bacteria can rapidly develop adaptation when exposed to sub-lethal concentrations of these oils.  相似文献   

10.
本试验旨在研究植物精油与丁酸钠的体外协同抑菌效果。采用牛津杯法,测定肉桂醛、百里香酚和香兰素对于4种细菌(大肠杆菌、沙门氏菌、产气荚膜梭菌、乳酸菌)的抑菌效果。并将单方和复合植物精油分别与丁酸钠复配,测定其抑菌效果。结果表明:3种植物精油均对大肠杆菌、沙门氏菌、产气荚膜梭菌有明显抑制作用,但对乳酸菌无抑制作用,在相同浓度下,抑菌效果为肉桂醛香兰素百里香酚。肉桂醛与香兰素复合植物精油抑菌效果优于单方植物精油,当肉桂醛与香兰素的质量比为6∶1时抑菌效果最佳。丁酸钠没有显示出抑菌作用,但丁酸钠与植物精油复合可明显降低植物精油的使用量。综上所述,不同植物精油的复合具有协同作用,植物精油和丁酸钠之间也存在着协同作用。  相似文献   

11.
Reasons for performing the study: The maternal recognition of pregnancy (MRP) signal in the mare has not been determined, although oestrogens have been proposed as a potential candidate. Objectives: To determine effects of intrauterine administration of oestrogen and various oils on cyclic luteolysis in the mare. Hypothesis: Intrauterine oestradiol or fatty acids may suppress luteolysis in the cycling mare when administered during late dioestrus. Methods: A single 1 ml dose of slow‐release oestradiol (10 mg/ml) in fractionated coconut oil was infused into the uterine lumen of cycling mares on Days 6, 8, 10, 12 or 14 post ovulation (n = 12 in each group). Four further groups, each of 12 mares, received an intrauterine infusion of either 1 ml of fractionated coconut oil, peanut oil, mineral oil or a slow‐release preparation of oestradiol (10 mg/ml) in mineral oil on Day 10 post ovulation. Serial blood samples were assayed for progesterone concentrations to monitor luteal function. Results: Intrauterine administration of oestradiol in fractionated coconut oil showed peak efficacy at Day 10 when luteolysis was delayed in 11/12 (92%) mares. The ability of the treatment to delay luteolysis was not significantly different when administered on Days 8 (9/12; 75%), 12 (10/12; 83%) or 14 (6/12; 50%) of dioestrus, but declined significantly when given on Day 6 (3/12; 25%). Oestradiol was not needed to initiate luteostasis since fractionated coconut oil alone or peanut oil administered at Day 10 induced the same high rate of luteal persistence (11/12; 92% for both oils). In contrast, mineral oil did not prolong luteal lifespan, either when administered alone (2/12; 17%) or combined with oestradiol (3/12; 25%). Conclusion: These results do not unequivocally rule out a possible involvement of embryonic oestrogens in MRP in the mare but suggest it is unlikely. The results demonstrate that plant oils can postpone luteolysis, suggesting they may modulate synthesis or release of prostaglandins from the mare's endometrium. Potential relevance: Administration of fractionated coconut or peanut oil on Day 10 post ovulation provides an effective and practical method of prolonging luteal function (‘pseudopregnancy’) thereby suppressing unwanted oestrous behaviour. Further studies to elucidate the mechanism by which this is achieved may increase understanding of both luteostasis and MRP signal in the mare.  相似文献   

12.
In vitro anaerobic incubations were used to determine the effect of different oils (LO-linseed, SO-sunflower, FO-fish oil) on trans fatty acid production in rumen fluid and to test if combining of monensin (MON) with the oils affects the interactions on trans fatty acid concentrations in mixed cultures of ruminal microorganisms. Two different sources of rumen fluid were used; the inoculum from the sheep fed hay and barley (80:20%)--the inoculum A and the inoculum from the sheep fed alfalfa and barley (80:20 %)--the inoculum B. The analyses showed that inoculum B contained more short chain fatty acids (SCFA), medium chain fatty acids (MCFA) and saturated fatty acids (SFA) than inoculum A. In contrast, inoculum A contained more unsaturated fatty acids (UFA) than inoculum B. The results show, that the oils affected the biohydrogenation of fatty acids (FA) by increasing the concentration of C18:0 (3-7 times) and trans C18:1 isomers (2-9 times). The concentration of two main intermediates of FA biohydrogenation-- cis 9, trans 11 C18:2 (CLA) and trans 11C18:1 (TVA) were increased with the oils, but FO was more efficient than other plant oils on CLA and TVA production.The monensin treatment had similar effect on FA metabolism as the oil treatment in comparison to unincubated control. The interactions of monensin treatment with the oils were characterized with decrease (LO+MON, SO+MON) or increase (FO+MON) of the proportions of C18:0 and trans C18:1 isomers in comparison to oil treatment.The highest concentrations of two main isomers--CLA,TVA were found in the samples containing fish oil and monensin. In conclusion, fish oil treatment and monensin with fish oil treatment was more efficient than other plant oils in the effect on trans fatty acid production (mainly CLA and TVA) in fermentation fluid in vitro.  相似文献   

13.
Na YE  Kim SI  Bang HS  Kim BS  Ahn YJ 《Veterinary parasitology》2011,178(3-4):324-329
The toxicity of two cassia oils, four cinnamon oils and (E)-cinnamaldehyde and (E)-cinnamic acid and 34 structurally related compounds to adult Dermanyssus gallinae (De Geer) collected from a poultry house was examined using a vapour-phase mortality bioassay. Results were compared with those of dichlorvos, a conventional acaricide. The cassia and cinnamon oils (cinnamon technical, cinnamon #500, cassia especial, cassia true, cinnamon bark and cinnamon green leaf) exhibited good fumigant toxicity (LD(50), 11.79-26.40 μg cm(-3)). α-Methyl-(E)-cinnamaldehyde (LD(50), 0.45 μg cm(-3)) and (E)-cinnamaldehyde (0.54 μg cm(-3)) were the most toxic compounds and the toxicity of these compounds was comparable to that of dichlorvos (0.30 μg cm(-3)). Potent fumigant toxicity was also observed in allyl cinnamate, ethyl-α-cyanocinnamate, (E)-2-methoxylcinnamic acid and (Z)-2-methoxylcinnamic acid (LD(50), 0.81-0.92 μg cm(-3)). Structure-activity relationships indicate that structural characteristics, such as types of functional groups and carbon skeleton rather than vapour pressure parameter, appear to play a role in determining toxicity. The essential oils and compounds described merit further study as potential acaricides for the control of D. gallinae populations as fumigants with contact action due to global efforts to reduce the level of highly toxic synthetic acaricides in the agricultural environment.  相似文献   

14.
采用水蒸气蒸馏法提取北京柠檬叶片、枝干和果皮的精油,并进行GC-MS分析,共鉴定出38种成分,其中叶片23种,枝干21种,果皮29种。3份精油主要挥发油成分均为D-柠檬烯,相对含量分别为52.85%、53.03%和51.23%;共有成分14种,特异性成分分别有4种、3种和14种。通过对3种食源性细菌的抑菌活性的测定,3份柠檬精油均有一定程度的抑菌作用,其中,叶片精油对大肠埃希氏菌和金黄色葡萄球菌抑菌效果最佳,且抑菌圈直径最大;果皮精油对伤寒沙门氏菌的抑菌效果最佳,抑菌圈最大。研究结果表明,柠檬不同部位精油活性成分含量差异较大,在对其开发利用时,可考虑各自优势,合理利用柠檬的叶片、枝干和果皮,为柠檬资源合理化和精细化的开发利用提供一定的科学依据。  相似文献   

15.
为了寻找柑橘木虱无公害防治新方法,采用行为生测法,测定了45种植物精油对柑橘木虱成虫的行为反应,并从中筛选出柠檬桉、欧芹、艾纳香、柠檬马鞭草、山鸡椒、芫荽、尤加利、花梨木、松共9种对柑橘木虱具有显著驱避作用的植物精油进行不同浓度的驱避效果比较。结果表明：当浓度为10-2、10-3、10-4时,柠檬桉、欧芹、艾纳香、柠檬马鞭草、山鸡椒、芫荽、尤加利、松精油对柑橘木虱均具有显著驱避作用,且随着精油浓度的提高驱避作用增强;而花梨木精油仅在浓度为10-2对柑橘木虱具有显著驱避效果,但在浓度为10-4时却表现显著的引诱作用。此外,植物精油间的驱避率比较结果表明芫荽与欧芹精油对柑橘木虱具有较好的驱避活性,有望用于开发柑橘木虱防治新方法。  相似文献   

16.
The acaricial activity of 56 plant essential oils against poultry house-collected adult Dermanyssus gallinae De Geer was examined using direct contact and fumigation methods. In a filter paper contact bioassay, 100% mortality at 0.07 mg cm−2 was observed in bay, cade, cinnamon, clove bud, coriander, horseradish, lime dis 5F, mustard, pennyroyal, pimento berry, spearmint, thyme red and thyme white oils, whereas the mortality of these oils was significantly decreased at 0.02 mg cm−2. In fumigation tests with adult D. gallinae at 0.28 mg cm−2, cade, clove bud, coriander, horseradish and mustard oils were more effective in closed containers than in open ones, indicating that the effect of these essential oils was largely due to action in the vapour phase. Plant essential oils described herein merit further study as potential D. gallinae control agents.  相似文献   

17.
为探讨不同的转群时间及转群前后喷洒精油对仔猪断奶应激的影响,优化仔猪断奶转群模式,试验选择28日龄、断奶体重（7.00±0.50）kg的杜×长×大三元杂交断奶仔猪192头,随机分为4组,每组3个重复,每个重复16头。采用2×2两因素试验设计,分别探讨不同转群时间（08：00、20：00）及是否喷洒精油（喷洒、不喷洒）对断奶仔猪腹泻率、死亡率、血液生化指标、氧化指标及免疫指标的影响。结果表明：转群后1、8、24 h,各试验组仔猪血清总蛋白（TP）和白蛋白（ALB）含量差异均不显著（P>0.05）;转群后1和8 h,晚上转群组仔猪血糖（GLU）含量低于早上转群理组,喷洒精油后GLU进一步降低;仔猪转群后1、8、24 h,各试验组仔猪血清中皮质醇（COR）和丙二醛（MDA）水平随转群后时间的增加而降低。转群后1和8 h,喷洒精油的两组仔猪血清MDA水平显著低于不喷组（P<0.05）,24 h后血清COR水平显著下降（P<0.05）;转群后1、8、24 h,各处理组仔猪血清中免疫球蛋白A（IgA）、免疫球蛋白M（IgM）、免疫球蛋白G（IgG）含量无显著差异（P>0.05）,转群后1和24 h,早上转群但不喷洒精油组仔猪血清白细胞介素-10（IL-10）与晚上转群且不喷洒精油组无显著差异（P>0.05）,而喷洒精油后,IL-10水平均显著下降（P<0.05）,以晚上转群且喷洒精油组仔猪血清IL-10水平最低。综上所述,晚上转群对断奶仔猪的应激程度小于早上转群,喷洒精油能进一步缓解应激,晚上转群并喷洒精油是减少仔猪断奶转群的理想模式。  相似文献   

18.
The effects of 18 essential oils, yeast, Quebracho tannin and Quillaja saponin on ruminal methane and gas production (GP) were studied in vitro. A lactating cow diet was incubated with rumen inoculum. Doses of the additives (mg/L) were: essential oils = 500; tannin = 67; yeast = 8.35 and 16.7; and saponin = 300. Lemongrass, estragole, eugenol, geraniol, limonen, thyme oil and thymol produced less gas (overall mean 33.8 mL/200 mg dry matter (DM)) than control (43.6 mL/200 mg DM; P < 0.001). Methane produced (mL/200 mg DM) by guaiacol (10.7), lemongrass (9.6), limonene (11.4), thyme oil (10.9) and thymol (2.1) was lower than control (12.5) (P < 0.001). Methane percentage on total GP was lower (P < 0.001) for cinnamic alcohol (25.4), guaiacol (24.5), thymol (19.7) and vanillin (26.3) than control (28.8). In a second experiment, thymol, guaiacol and yeast were added to the diet of dry fistulated cows to determine in situ neutral detergent fiber digestibility (NDFD) of six forages and in vivo dietary NDFD. Thymol and yeast decreased in situ NDFD after 24 h (33.9% and 33.5% vs. 38.1%; P = 0.008). Thymol decreased in vivo total tract NDFD (40.8% vs. 51.4%; P = 0.02). Differences in GP and methane levels were registered within classes of additives. A careful selection of additives may allow for the manipulation of ruminal fermentation.  相似文献   

19.
Methods for the chemical analysis of toxic plant substances in the rumen of ruminants are of importance for the diagnosis of intoxications with poisonous plants. The present work establishes a method to estimate monoterpene components of the essential oil of thuja (Thuja orientalis, Cupressaceae) in these types of samples. Alpha-thujone, which is regarded as the toxic principle, is present at a concentration of 50-60% in the essential oil. The rumen simulation technique (Rusitec) was used to simulate natural digestion. Chopped twigs of thuja were subjected to rumen content in a closed container with an overflow device. The flow of saliva was simulated by the continuous addition of a buffer solution. Samples for analysis were taken from the overflow at 24 and 48 h. A further sample was taken from the remaining liquid fraction of the rumen content in the container at 48 h. The essential oils were extracted with hexane and concentrated. A quantitative determination was done by capillary gas chromatography. Together in the three fractions analysed this resulted in total mean recoveries of 6.8% for alpha-thujone, 5.3% for beta-thujone, 18.9% for fenchone and 27.8% for camphor. The observation that the thujones were recovered to a lesser extent than other oil components is evidence of their fast decomposition in the rumen medium. Under these circumstances the calculated detection limit is 100-200 g thuja twigs in cows with rumen volumes of 60-100 litres. The main essential oil degradation products found in the rumen fluid of all three fractions in the Rusitec system were discovered to be iso-3-thujanol, neo-3-thujanol, carvomenthol and carvomenthone.  相似文献   

20.
The chemical composition of essential oils from three species of plants belonging to the Eucalyptus genus was determined and, their insecticidal effects on egg, larva and adult phases of Lutzomyia longipalpis were assessed. The insects were collected in the municipality of Sobral in the State of Ceará, Brazil. Five treatments with different concentrations were performed along with two negative controls, distilled water and Tween 80 (3%), and a positive control, cypermethrin (0.196 mg/ml). The tests were carried out in plastic pots internally coated with sterile plaster and filled with a substrate made of rabbit feces and crushed cassava leaves. The eggs, larvae and adults were sprayed with the oils. The hatched larvae were counted for 10 consecutive days and observed until pupation. Insect mortality was observed after 24, 48 and 72 h. E. staigeriana oil was the most effective on all three phases of the insect, followed by E. citriodora and E. globulus oils, respectively. The major constituents of the oils were Z-citral and alpha-citral (E. staigeriana), citronellal (E. citriodora) and 1,8-cineole (E. globulus). The Eucalyptus essential oils constitute alternative natural products for the control of L. longipalpis since the median effective concentration (EC50) values revealed relevant action as compared with other natural products, some of their chemical constituents are already known for their insecticidal activity and these oils are produced in commercial scale in Brazil.  相似文献   

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