植物精油调控反刍动物瘤胃发酵的研究进展

饲料在反刍动物瘤胃内发酵过程中,造成能量和蛋白质的流失,降低饲料利用效率。植物精油因其低毒副作用及其所具有的天然性、营养性和生物活性,对反刍动物瘤胃发酵具有积极的调控作用,成为抗生素的理想替代品之一。文章主要综述了植物精油对反刍动物瘤胃微生物及瘤胃发酵的影响及调控作用。     

植物精油降低反刍动物瘤胃甲烷产量的研究进展

植物精油是从植物中蒸馏提取出来的具有挥发性和芳香性的植物次生代谢物,大量反刍动物体内外试验结果表明,植物精油能够降低反刍动物瘤胃甲烷产量,其作用机制主要包括两方面：一是直接抑制产甲烷菌的生长,进而减少甲烷产生;二是通过减少与产甲烷菌共生的细菌、古菌或原虫等微生物数量,间接减少甲烷产生。但未来要将植物精油广泛应用到实践生产中,仍面临巨大挑战。本文着重对植物精油降低反刍动物瘤胃甲烷产量的研究进展进行综述,旨在为植物精油在反刍动物生产中的科学应用提供参考。     

植物精油在反刍动物生产中的应用

植物精油是从植物中萃取的混合物,主要成分为单萜、倍半萜、酚类、醇、醚、醛和酮等,已被证明是很好的饲料替抗添加剂,能提高动物生产性能、肠道菌群和动物福利,但在反刍动物生产中的应用报道较少。该文主要从精油对反刍动物乳房炎的防治、体内外寄生虫作用效果和生产性能等方面进行阐述,讨论植物精油可能的作用机制,并提出未来的研究方向。     

植物精油在反刍动物生产中的应用研究进展

植物精油（EOs）是经蒸馏等方式从植物组织中提取的易挥发油状芳香物质,具有良好的抗菌、抗氧化和抗炎活性。EOs能够提高动物机体的免疫性能并促进动物生长,被认为具有良好的替抗潜力,近年来在反刍动物上的应用逐渐广泛。本文综述了EOs对反刍动物瘤胃发酵、甲烷产量、动物生产性能、畜产品品质及机体免疫性能的影响及其作用机制,旨在为EOs在反刍动物生产中的推广应用提供理论参考。     

复合植物精油对肉牛生长性能、养分消化及氮代谢的影响

文章旨在评估复合植物精油对肉牛生长性能、营养物质表观消化及氮代谢的影响.试验将平均体重为(203.16±0.29)kg的108头肉牛随机分为3组,每组36头,每6头牛为1个重复.对照组饲喂全混合日粮,同时自由采食小麦秸秆,T1组和T2组分别饲喂全混合日粮+30和60 mg/kg植物精油,自由采食小麦秸秆.经过28周的饲...     

植物精油对蛋鸡生产性能影响的研究进展

近年来,抗生素在家禽产业中的使用暴露出越来越多的弊端,为保证家禽业健康快速地发展,人们对植物精油的研究越来越多,利用植物精油来替代抗生素,以促进家禽产业的绿色发展.文章针对植物精油对家禽的生产性能作一综述,以期对家禽的生产提供理论参考.     

植物提取物对反刍动物生产性能及瘤胃发酵的影响

长期使用抗生素会引发耐药菌的产生,对动物和人的健康带来安全隐患,因此,研究开发新的天然饲料添加剂成为近年来的热点。本文讨论了植物及植物提取物（单宁、挥发油等）对反刍动物生产性能及消化,特别是对瘤胃发酵作用方式的影响。     

植物精油调控反刍动物瘤胃发酵和甲烷排放的研究进展

植物精油是一类从植物中萃取出来的具有芳香气味的油状液体,具有广谱抗菌性,对革兰氏阳性菌和革兰氏阴性菌均有一定的抑制作用。植物精油可减少反刍动物瘤胃中蛋白质的降解,降低其氨排放量,从而调控瘤胃中的氮代谢。植物精油在抑制反刍动物肠道甲烷排放方面表现出积极作用,具有作为饲料添加剂来调控瘤胃发酵的潜质。该文旨在阐述植物精油对瘤胃发酵和甲烷排放的调控作用,探讨其在生产中广泛应用的可行性。     

植物精油对瘤胃发酵的调控作用

瘤胃微生物可降解饲料中营养成分来生成挥发性脂肪酸并合成微生物蛋白来为反刍动物提供能量和蛋白。但瘤胃发酵过程中会有能量损失和蛋白利用效率低下现象发生,进而降低了反刍动物生产性能。植物精油可以与微生物细胞膜作用,可抑制一些革兰阴性菌和阳性菌,进而调控瘤胃微生物发酵作用。论文主要介绍近年来植物精油对瘤胃发酵调控作用研究近况,讨论其作为瘤胃发酵调控剂的可行性。     

植物精油对泌乳期奶牛生产性能养分消化、瘤胃发酵及氮平衡的影响

本研究以泌乳期奶牛为研究对象,研究全混合日粮中补充植物精油对其养分摄入量、表观消化率、瘤胃发酵及氮和能量平衡的影响.试验将泌乳性能一致的16头荷斯坦奶牛随机分为2组,每组8个重复,每个重复1头牛.对照组饲喂基础全混合日粮,处理组饲喂基础全混合日粮+150 mg/kg植物精油,试验为期7周.结果:植物精油组奶牛干物质、有...     

植物挥发油的生物学活性及其在反刍动物生产中的应用研究进展

本文综述了植物挥发油的生物学活性,同时对挥发油在反刍动物上应用进展作了概述,旨在为研究和开发植物挥发油调控瘤胃发酵提供依据。     

Effect of monensin and essential oils on performance and energy metabolism of transition dairy cows

This work examined preventive effects of a dietary and a medical intervention measure on postpartum (p.p.) ketogenesis in dairy cows overconditioned in late pregnancy. Sixty German Holstein cows were allocated 6 weeks antepartum (a.p.) to three high body condition score (BCS) groups (BCS 3.95 ± 0.08) and one low BCS group (LC, BCS 2.77 ± 0.14). Concentrate proportion in diet a.p. was higher (60% vs. 20%) and increase in proportion p.p. from 30% up to 50% decelerated (3 vs. 2 weeks) in high BCS groups. High BCS cows received a monensin controlled‐release capsule (CRC) (HC/MO), a blend of essential oils (HC/EO) or formed a control group (HC). Performance parameters and energy status were evaluated in three periods [day (d) ?42 until calving, one until 14 days in milk (DIM), 15 until 56 DIM]. Feed efficiency was 65% and 53% higher in HC/MO than in LC (p < 0.001) and HC groups (p = 0.002) in the second period. Milk fat content was higher in HC/EO (5.60 vs. 4.82%; p = 0.012) and milk urea higher in HC/MO (135 mg/kg) than in LC cows (107 mg/kg; p < 0.001). Increased p.p. levels of non‐esterified fatty acids in serum were found in HC (p = 0.003), HC/MO (p = 0.068) and HC/EO (p = 0.002) in comparison with LC cows. Prevalence of subclinical and clinical ketosis was 54% and 46%, respectively, in HC group. Monensin decreased the prevalence to 50% and 7% respectively. Ruminal fermentation pattern showed higher proportions of propionate (23.43 mol % and 17.75 mol %, respectively; p < 0.008) and lower acetate:propionate ratio (2.66 vs. 3.76; p < 0.001) in HC/MO than HC group. Results suggest that a monensin CRC improved energy status and feed efficiency of transition dairy cows while essential oils failed to elicit any effect.     

发酵豆粕和植物精油对断奶仔猪生产性能的影响

本试验探讨了在日粮中使用发酵豆粕替代普通豆粕并添加植物精油对仔猪生产性能的影响，为发酵豆粕和植物精油在仔猪日粮中的利用提供科学依据。结果表明，日粮中添加发酵豆粕和植物精油，仔猪末重和平均日增重分别提高14.81%和19.51%，提高仔猪平均日采食量6.84%，而降低料重比和单位增重成本分别为10.71%和7.67%；有效降低仔猪腹泻率50.67%。     

苯甲酸和精油对肉鸡生长性能、抗氧化状态和肠道微生物群的影响

本研究开展了3个饲养试验,旨在探讨苯甲酸和精油单独或联合使用对肉鸡生长性能、肠道微生物含量及肝脏抗氧化性能的影响.试验1和2均选择1日龄肉鸡450只,分为3组,每组5个重复,每个重复30只.对照组均饲喂相同的基础日粮,试验1处理组肉鸡分别饲喂基础日粮添加1.5和3?g/kg苯甲酸,试验2处理组肉鸡分别饲喂日粮添加2和4...     

Chitosan nano-encapsulation improves the effects of mint,thyme, and cinnamon essential oils in broiler chickens

ABSTRACT

1. This study was conducted to evaluate the effects of chitosan nano-encapsulating mint (MEO), thyme (TEO) and cinnamon (CEO) essential oils (EOs) used in the diet on performance, immune responses and intestinal bacteria population in broiler chickens.

2. A total of 600 mixed-sex, 1-d-old Ross 308 broiler chicks were used in a 2 × 4 factorial experiment as completely randomised design with 8 experimental groups (diets) with 5 replicates of 15 chicks each (totally 40 pens). The eight experimental diets consisted of no EO and free distiller water (control); no EO and chitosan nano-encapsulated (CNE) distiller water; and other six treatments with free or CNE form of MEO, TEO and CEO (added at 0.025%, 0.04% and 0.055% respectively to starter, grower and finisher diets).

3. Both EOs and the CNE form had significant (P < 0.05) benefits on improving body weight gain, and feed conversion ratio in periods of 29–42 and 1–42 days. The highest effect was (P < 0.05) obtained in birds receiving TEO, which was intensified by nano-encapsulation. Breast percentage was improved by nano-encapsulation (P < 0.05). The EOs (especially TEO and CEO) and CNE form improved (P < 0.05) serum IgY and IgM concentrations (at 35 and 42 days) and intestinal Lactobacillus spp. and E. coli populations (at 42 days) in broilers. Nano-encapsulated EOs, especially TEO and CEO had (P < 0.05) the largest effect on increasing IgY₄₂ concentrations and the microbial populations.

4. The tested EOs, especially TEO, improved more of the evaluated traits in broiler chickens. Also, Chitosan nano-encapsulation because of its ideal properties can be an effective, suitable and inexpensive method for protecting bioactive compounds and improving effects of the herbal EOs especially thyme in broiler chickens.

     

Rosemary oil,clove oil,and a mix of thyme-orange essential oils inhibit Salmonella and Campylobacter in vitro

The demand for foods that are free of pathogens and chemical residues has increased interest in the use of plant-based products as natural antimicrobials. Essential oils (EO) from plants are natural compounds that have been shown to have antimicrobial properties against food-borne pathogens. The objective of the current study was to determine the ability of various concentrations of 4 selected EO to inhibit Salmonella enterica (3 different serovars and a cocktail of all 3) and Campylobacter (2 strains of Campylobacter jejuni, one strain of Campylobacter coli, and a cocktail of all 3). The disc diffusion method was used to screen the oils of thyme, orange, rosemary, and clove oil. The minimum inhibitory concentration or minimum bactericidal concentration of the EO was determined using a 2-fold broth dilution method at concentrations ranging from 0.0008 to 1.000% (vol/vol). Two independent experiments were performed. Zones of inhibition (ZI) were expressed in millimeters and concentrations were expressed in percentages. All the oils demonstrated antibacterial activity against the strains tested. However, thyme oil demonstrated the strongest inhibitory activity than other oils against Salmonella (ZI of 18.5 mm). In general, Campylobacter was more susceptible to the antibacterial activity of EO, with plates containing thyme or clove oil showing no growth. Orange oil was also highly effective on Campylobacter, with a mean ZI of 17.5 mm. The least expensive treatment effective against both Salmonella and Campylobacter was a combination of 100% concentrations of thyme and orange oil combined on a 50:50 proportion. Tested on the same strains of bacteria, the thyme-orange combination (TOC) had a mean ZI of 20.5 mm for Salmonella and 21.3 mm for Campylobacter. Thyme-orange combination demonstrated a synergetic effect against Salmonella, but no such effect was noticed for Campylobacter. On average, 0.14% TOC was required to inhibit both pathogens. Hence, TOC can be considered as a potential antimicrobial for future studies on food systems.     

Performance,rumen fermentation and blood metabolites of dairy calves fed starter mixtures supplemented with herbal plants,essential oils or monensin

This study evaluated the supplementation effects of three herbal plants (thyme [THY], eucalyptus [EUC] and celery [CEL]), a commercial phytogenic additive ?containing essential oils (PFA‐EO, Digestarom^® P.E.P.) and monensin (MON) in calf starter on performance, rumen fermentation and blood metabolites during pre‐ (days 3–55) and post‐weaning (days 56–70). Sixty‐six Holstein dairy calves (3 days of age, 41.2 ± 3 kg of BW) were allocated to one of six starters supplemented with: (i) no additives (CON), (ii) MON (30 mg/kg), (iii) THY (23 g/kg), (iv) CEL (23 g/kg), (v) EUC (23 g/kg) and (vi) PFA‐EO (3 g/kg). All the calves were offered starters ad libitum plus 6 L of whole milk daily. Starter intake tended to be the highest in calves fed PFA‐EO and THY; intermediate in calves fed CON, MON and EUC; and the lowest in those fed CEL. Average daily gain (ADG) and feed efficiency (FE) remained unaffected by dietary treatments during the pre‐weaning. During the post‐weaning period, ADG and FE ?were greatest in calves fed EUC followed by those fed CON, MON, PFA‐EO and THY, and then in those fed CEL. No differences were observed among the treatments in skeletal growth, faecal score, rumen pH or ammonia‐N concentration. Compared to calves fed CON and MON, those fed the herbal plants or PFA‐EO tended to recorded higher molar proportions of acetate and butyrate, and the acetate: propionate ratio. Blood malondialdehyde level did not differ among treatments, but calves on CON had the highest glucose concentration, and those fed PFA‐EO recorded the highest value for β‐hydroxyl butyrate on day 70. In conclusion, the results indicate that the three herbs and PFA‐EO are capable of modulating some of the rumen fermentation parameters and blood metabolites as well as eucalyptus could potentially be a better alternative to monensin for improving post‐weaning performance.