Ultrastructurally different muscle cell types in Eisenia foetida (Annelida,Oligochaeta)

Muscles in the body wall, intestinal wall, and contractile hemolymphatic vessels (pseudohearts) of an oligochaete anelid (Eisenia foetida) were studied by electron microscopy. The muscle cells in all locations, except for the outer layer of the pseudohearts, are variants of obliquely striated muscle cells. Cells comprising the circular layer of the body wall possess single, peripherally located myofibrils that occupy most of the cytoplasm and surround other cytoplasmic organelles. The nuclei of the cells lie peripherally to the myofibrils. The sarcomeres consist of thin and thick myofilaments that are arranged in parallel arrays. In one plane of view, the filaments appear to be oriented obliquely to Z bands. Thin myofilaments measure 5–6 nm in diameter. Thick myofilaments are fusiform in shape and their width decreases from their centers (40–45 nm) to their tips (23–25 nm). The thin/thick filament ratio in the A bands is 10. The Z bands consist of Z bars alternating with tubules of the sarcoplasmic reticulum. Subsarcolemmal electron-dense plaques are found frequently. The cells forming the longitudinal layer of the body wall musculature are smaller than the cells in the circular layer and their thick filaments are smaller (31–33 nm centrally and 21–23 nm at the tips). Subsarcolemmal plaques are less numerous. The cells forming the heart wall inner layer, the large hemolymphatic vessels, and the intestinal wall are characterized by their large thick myofilaments (50–52 nm centrally and 27–28 nm at the tips) and abundance of mitochondria. The cells forming the outer muscular layer of the pseudohearts are smooth muscle cells. These cells are richer in thick filaments than vertebrate smooth muscle cells. They differ from obliquely striated muscle cells by possessing irregularly distributed electron-dense bodies for filament anchorage rather than sarcomeres and Z bands and by displaying tubules of smooth endoplasmic reticulum among the bundles of myofilaments. © 1995 Wiley-Liss, Inc.     

Vermicomposting of cattle and goat manures by Eisenia foetida and their growth and reproduction performance

Vermicomposting is commonly adopted for the treatment of livestock organic wastes. In the present study, two types of livestock manure were used for culturing of the earthworm, Eisenia foetida. Each treatment group consisted of six replicates and worm vermicasts were examined after 5 weeks. The concentrations of total C, P and K in goat manure vermicasts were higher than those in cattle manure vermicasts. Cattle vermicasts had a higher N content than goat vermicasts but the C:N ratio of fresh manure was higher than that of vermicasts for both materials. Earthworm biomass and reproductive performance, in terms of number of worms after 5 weeks of experiment, were higher in cattle manure than in goat manure. The cocoon production per worm in cattle manure was higher than in goat manure. However, the hatchability of cocoons was not affected by manure treatments. In conclusion, cattle manure provided a more nutritious and friendly environment to the earthworms than goat manure.     

Vermicomposting of mixed solid textile mill sludge and cow dung with the epigeic earthworm Eisenia foetida

This paper reports the results of a study of vermicomposting with Eisenia foetida of solid textile mill sludge mixed with cow dung in different ratios in a 90 days composting experiment. Vermicomposting resulted in significant reduction in C:N ratio and increase in TKN. Total K and Ca were lower in the final cast than the initial feed mixture. Microbial activity measured as dehydrogenase activity increased up to 75 days and decreased on further incubation. Total P was higher in the final product than the initial feed mixture. Total heavy metal contents were lower in the final product than initial feed mixture. Solid textile mill sludge can be potentially useful as raw substrate in vermicomposting if mixed with up to 30% cow dung (on dry weight basis). The growth and cocoon production of the worm species in different feed mixtures were also investigated.     

不同类型污染土壤中赤子爱胜蚓对伴矿景天重金属吸收的影响初报

伴矿景天Sedum plumbizincicola是我国发现和报道的镉/锌(Cd/Zn)超积累植物,在土壤Cd污染修复方面已开展实际应用。由于超积累植物伴矿景天在不同类型土壤下的生长能力以及对镉锌的去除效果存在较大差异,因此需引入强化修复技术为植物修复提供辅助作用。作为大型土壤动物,蚯蚓对植物生长的促进作用已有较多研究,但其对伴矿景天生长和重金属吸取效率的影响则鲜有报道,为探究赤子爱胜蚓对不同类型土壤种植下的伴矿景天是否具有强化修复效应,以及不同类型土壤下的强化修复效应差异,设计以下盆栽试验。通过在常湿淋溶土(Perudic Luvisols)、水耕人为土(Stagnic Anthrosols)、湿润雏形土(Udic Cambisols)3种土壤上种植伴矿景天、引入赤子爱胜蚓Eisenia foetida,探究赤子爱胜蚓对伴矿景天生长及Cd/Zn吸收性的影响。选取Cd有效性较高、修复潜力较大的水耕人为土(Stagnic Anthrosols)进行第二季盆栽修复试验。第一季修复结果显示,在酸性的常湿淋溶土中,添加赤子爱胜蚓使伴矿景天地上部生物量较对照处理增加了106%,Cd和Zn吸收量分别提高了72.0%和36.0%,且蚯蚓结合伴矿景天的处理修复后土壤Cd有效性进一步降低,其余两种土壤仅添加蚯蚓无强化修复效应;第二季结果显示,同时添加秸秆和蚯蚓,可强化中性的水耕人为土上种植的伴矿景天生长,增大植物地上部生物量和Cd/Zn吸收量。结果表明,添加蚯蚓可增强伴矿景天在常湿淋溶土中的养分吸收,提高生物量,以此强化其修复效应。在水耕人为土中,外加秸秆可作为蚯蚓强化伴矿景天修复的配套技术。     

Autofluorescence as a tool to study mucus secretion in Eisenia foetida

Autofluorescence in living cells is due to the presence of endogenous substances that emit fluorescence upon excitation by incidental light. A type of fluorescence, bioluminescence, has been suggested to be linked to mucus secretion in earthworms; however, the origin and the physiological function of this fluorescence are not clear. The aims of this work were to describe autofluorescence in the earthworm Eisenia foetida by SEM, CLSM, and fluorescence microscopy and to examine the possible mechanism of mucus secretion by video microscopy. Earthworms were stimulated either chemically or electrically to induce the secretion of yellow mucus, which was subsequently studied by video microscopy. Mucus was released from the body wall and near the mouth. This phenomenon was associated with autofluorescence and involved at least four distinct stages: release of vesicles, formation of granules, muscular contraction, and organization of strands. The fluorescent molecules were stored in vesicles bound to the membranes. These vesicles were intact when shed from the body. The vesicles were stable but also changed to a granular material or formed strands. Video analyses demonstrated that secretion was dependent on the type of stimulus.     

三种兽药添加剂对土壤赤子爱胜蚓的毒理学研究

喹乙醇、阿散酸和土霉素是应用极广的兽药添加剂,在畜牧业的发展中起着特殊的作用,但其使用不当或过量使用会给环境带来很大危害.采用土壤中的重要生物赤子爱胜蚓作为生物材料,分别研究了喹乙醇、阿散酸和土霉素对赤子爱胜蚓的急性毒性和对赤子爱胜蚓体腔细胞DNA的损伤.结果表明,喹乙醇溶液法LC₅₀>2000mg·L^-1,滤纸法LC₅₀>5.71×10^-2mg·cm^-2,而阿散酸和土霉素在所设最大受试剂量内没有毒性.单细胞凝胶电泳试验结果表明,阿散酸没有引起蚯蚓体腔细胞DNA明显损伤;喹乙醇和土霉素均能引起一定程度的DNA损伤,中、高剂量组与阴性对照相比有极显著差异(P<0.01).因此,有必要加强对以上兽药添加剂,特别是喹乙醇和土霉素的管理,控制用药时间和剂量,以确保人体健康和环境安全.     

Development of a water hyacinth based vermireactor using an epigeic earthworm Eisenia foetida

The aim of this work was to investigate the potential of water hyacinth (WH) spiked with cow dung (CD) into vermicompost. Five vermireactors containing WH and CD in different ratios, were run under laboratory conditions for 147 days. The maximum worm growth was recorded in CD alone. Worms grew and reproduced favourably in 25% WH+75% CD feed mixture. Greater proportion of WH in feed mixture significantly affected the biomass gain, hatchling numbers and numbers of cocoons produced during experiments. In all the vermireactors, there was significant decrease in pH, TOC and C:N ratio, but increase in TKN, TK and TAP at the end. The heavy metals content in the vermicomposts was lower than initial feed mixtures. The results indicated that WH could be potentially useful as raw substrate in vermicomposting if mixed with up to 25% in cow dung (on dry weight basis).     

Reproductive potential of the earthworm Eisenia foetida

Summary Regression equations are provided for the earthworm Eisenia foetida with respect to age at which 50% of the population became clitellate at 25° C in relation to population density in activated sludge and in horse manure. Regression equations are provided for progeny per cocoon versus weight of cocoon, and weight of cocoon in relation to weight of parent; from these an equation is derived for progeny per cocoon relative to worm weight. Regression equations are given on (a) number of cocoons produced per adult in relation to age and population density from onset of adulthood to median peak production of cocoons, age 10 weeks, and from age 10 weeks to age 27 weeks, and (b) weight of worm in relation to population density and age between ages 5 and 27 weeks. From (a) and (b) a family of equations (c) are derived giving progeny per cocoon in relation to age of adult and population density. From equations (a) and (c) two families of equations are generated giving progeny per adult in relation to ascent to, and descent from, the median week of peak cocoon production in relation to population density. Data also are provided on age at which reproduction terminates in relation to population density, optimum population density for reproduction, and hatchability.     

赤子爱胜蚓对不同猪粪和秸秆的分解作用

通过赤子爱胜蚓对发酵后猪粪(粮食猪粪、饲料猪粪)和秸秆(水稻秸秆、玉米秸秆)及其不同质量比例(1∶1或3∶1)混合物料进行摄食分解后,对物料前后及不接种赤子爱胜蚓的对照样品理化性质进行分析,发现赤子爱胜蚓处理90 d后的不同物料质量均减少,减少的质量显著多于不接种蚯蚓的对照处理(P＜0.01).赤子爱胜蚓对猪粪与秸秆混合物料的分解量多于纯猪粪和纯秸秆(P＜0.01).猪粪与玉米秸秆的混合物,经蚯蚓处理后,混合物料减少的质量显著多于猪粪与水稻秸秆混合物中物料减少的质量(P＜0.05).经蚯蚓处理后,饲料猪粪混合比例为3∶1的物料质量损失显著多于混合比例为1∶1的物料质量损失(P＜0.01),而粮食猪粪混合比例为1∶1的物料质量损失与混合比例为3∶1的物料质量损失差异不显著(P＞0.05).接种赤子爱胜蚓后,物料的全氮和速效氮、全磷和速效磷以及全钾和速效钾的含量增加,有机质和pH值降低.粮食猪粪和玉米秸秆以质量1∶1的比例进行混合物料的有机质、速效氮、速效磷和速效钾含量变化幅度最大,表明赤子爱胜蚓对此混合物料的分解作用最大.本研究可为猪粪和作物秸秆的资源化利用提供理论依据.     

The cocoon-producing cells of Eisenia foetida (Annelida, Oligochaeta): a histochemical and ultrastructural study

Type 1 cells of the clitellar epithelium of Eisenia foetida secrete a protein resembling keratin in histochemical reaction. Ultrastructurally, type 1 cells are characterized by membrane-bound, pockmarked granules ranging in diameter from 1.0 to 3.0 micrometers. Immature granules often exhibit an organized microfibrillar substructure. Individual microfibrils are 17 +/- 1 nm in diameter. Type 2 cell secretion contains protein, nonsulfated acid mucosubstance, and neutral mucosubstance with 1,2-glycol groups. The coarsely fibrillar granules are membrane bound and vary in diameter from 0.5 to 1.0 micrometer. The necks of both type 1 and type 2 cells contain a peripheral ring of microtubules, 20 +/- 1 nm in diameter.     

Lipid and fatty acid composition of Eisenia foetida

It is found out that the content of lipids in the biomass of the studied populations of Eisenia foetida is rather high: 2.5-5.2% of the wet mass. The content of phospholipids is 40-55%, C27-sterols--1.5-3.4% of the mass of coarse extracts of lipids. Lipids of tissues contain also 47-54% of saturated (C10-C24) fatty acids as well as to 23% of monoene and to 13% of polyene unsaturated (C14-C22) fatty acids. The acids with the odd number of carbon atoms compose about 25% and acids with a branched carbon chain about 23% of the above percentage. Considerable content of lipids and biologically active fatty acids in tissues of the studied object permits considering it as a promising source of raw materials for production of valuable pharmacological preparations.     

Characteristics of cholinesterase of the earthworm Eisenia foetida

1. Except for pH optimum, reactivation and “aging”, the results indicate that the ChE of Eisenia foetida is distinct from acetylcholinesterase and butyrylcholinesterase.2. Propionylcholine was found to be a better substrate than acetylcholine, while butyrylcholine, benzoylcholine and acetyl-beta-methylcholine were found to be poor substrates for this ChE.3. Little or no tendency towards substrate inhibition was seen.4. The rate constants of inhibition by alkyl phosphates and carbamates favour the concept of this enzyme being a B-esterase, but different from the two main classes of ChE.5. The buffer-soluble and membrane-bound ChE showed no differences in substrate specificity and Michaelis-Menten constants.6. These enzymes separately also showed little or no tendency towards substrate inhibition.7. Crude homogenate, membrane-bound, buffer-soluble and Triton X-100 solubilized ChE, as well as fractions from isoelectric focusing are acted upon by inhibitors at rather similar rates.8. The presence of only one type of enzyme is therefore indicated.9. The existence of isoenzymes is not clearly indicated either by isoelectric focusing, by gel electrophoresis technique or density gradient centrifugation.10. The latter method indicated the molecular weight to be 108,000 ± 7000.     

Purification of a novel antibacterial short peptide in earthworm Eisenia foetida

Earthworms live in an environment with abundantpathogens. These pathogens are, firstly, bacteria living inwater or soil that are ingested during feeding or introducedinto the body following injury. Parasites, particularlylarval forms, which represent the dissemination phase,are another important group of potentially pathogenicagents. During the course of evolution, earthworms havedeveloped defense strategies against these living patho-gens [1,2]. Earthworms lack true antibodies and hence anada…     

Vermicomposting potential of Perionyx sansibaricus (Perrier) in different waste materials

The decomposition efficiency of Perionyx sansibaricus (Perrier) for vermicomposting was evaluated by using a variety of wastes such as agriculture waste, farm yard manure and urban solid waste. Vermicomposting resulted in significant increase in total N (80.8-142.3%), phosphorous (33.1-114.6%) and potassium (26.3-125.2%), whereas decrease in organic C (14.0-37.0%) as well as C:N ratio (52.4-69.8%) in different experimental beddings. P. sansibaricus showed maximum biomass production, growth rate (mg day(-1)), mean cocoon numbers, and reproduction rate (cocoon worm(-1)) in VLL (vegetable waste+leaf litter) as compared to other substrate materials. There was a consistent trend for earthworms' growth and reproduction rate, related to initial N-content of the substrate (P<0.05), but there was no clear effect of C:N ratio of the composted material on earthworm cocoon numbers and weight gain. Earthworm showed minimum total population mortality in VLL and maximum in HHCD (household waste+cow dung), after 150 days of experimentation. The increased level of plant metabolites in end product (vermicompost) and growth patterns of P. sansibaricus in different organic waste resources demonstrated the candidature of this species for wastes recycle operations at low-input basis.     

赤子爱胜蚓5个Dmrt基因的序列分析

本文采用简并PCR技术,扩增了赤子爱胜蚓Dmrt基因的DM结构域,经序列分析,获得了Dmrt基因家族的5个成员EfDmrt2、EfDmrt3、EfDmrt4a、EfDmrt4b、EfDmrt4c.与其他动物相关的Dmrt基因进行聚类分析,结果表明,不同进化地位动物的Dmrt基因DM域编码序列存在高度的同源性,显示Dmrt基因在系统进化上高度保守,序列上的相似性可能暗示它们在功能上的保守性.     

Vermicomposting: A management tool to mitigate solid waste

Solid waste management is a serious ecological problem in Saudi Arabia due to rapid industrialization, population growth and urbanization. Recycling and sorting are in their infancy in Saudi Arabia and huge amounts of mixed household and industrial wastes are still dumped without any pre-treatment. Solid waste management techniques such as incineration, pyrolysis and gasification have high investment costs. Composting and vermicomposting of solid organic waste have been considered as an economically viable and sustainable waste management technologies. However, wastes often contain pollutants, such as heavy metals that are toxic to decomposer micro-organisms. Thus, heavy metals are a challenge for the successful biological treatments. Waste may also contain a mixture of organic pollutants that certain microbes, such as micro-algae are known to degrade. The present review paper focuses on understanding the role of vermicomposting as a management tool in mitigating solid organic wastes. It is noteworthy to mention that the microbes also play a pivotal role in the degradation process, wherein the enzymes secreted during the process aid in decomposition of complex molecules into simpler compounds. Also, the extracellular polymeric substance secreted by the earthworm under metal stress serves a source of nutrient for the bacteria to flourish. Henceforth the goal of discussion in present review shows the way forward in using vermicomposting as a novel approach in dealing with solid organic waste.     

Biological effects of 6 mT static magnetic fields: a comparative study in different cell types

The present work was a comparative study of the bio-effects induced by exposure to 6 mT static magnetic field (MF) on several primary cultures and cell lines. Particular attention was dedicated to apoptosis. Cell viability, proliferation, intracellular Ca(2+) concentration and morphology were also examined. Primary cultures of human lymphocytes, mice thymocytes and cultures of 3DO, U937, HeLa, HepG2 and FRTL-5 cells were grown in the presence of 6 mT static MF and different apoptosis-inducing agents (cycloheximide, H(2)O(2), puromycin, heat shock, etoposide). Biological effects of static MF exposure were found in all the different cells examined. They were cell type-dependent but apoptotic inducer-independent. A common effect of the exposure to static MF was the promotion of apoptosis and mitosis, but not of necrosis or modifications of the cell shape. Increase of the intracellular levels of Ca(2+) ions were also observed. When pro-apoptotic drugs were combined with static MF, the majority of cell types rescued from apoptosis. To the contrary, apoptosis of 3DO cells was significantly increased under simultaneous exposure to static MF and incubation with pro-apoptotic drugs. From these data we conclude that 6 mT static MF exposure interfered with apoptosis in a cell type- and exposure time-dependent manner, while the effects of static MF exposure on the apoptotic program were independent of the drugs used.     

赤子爱胜蚓对森林凋落物的分解效率

蚯蚓是帽儿山林区的主要土壤动物类群。饲养实验表明,赤子爱胜蚓(Eiseniafoetida)对不同种类、不同腐解程度的木本植物叶片的摄食量不同,对未分解叶的食性偏好依次为:白桦(Betulaplatyphylla)>杨(Populusdavidiana)>红松(Pinuskoraiensis)>蒙古栎(Quercusmongolica),对半分解叶的食性偏好依次为:杨>红松>蒙古栎>白桦,对同种叶片半分解叶的消耗能力大于未分解叶。这表明叶片种类和叶子腐化程度是影响蚯蚓摄食偏好的两个主要因素,混交林比纯林更有利于蚯蚓对难腐化叶片种类的分解。研究还表明,赤子爱胜蚓生物量在盛夏、春末以增重为主,夏初、秋初以失重为主,对落叶的消耗能力随种群生物量增大而增大,摄食量随温度的升高而增大,说明影响蚯蚓分解能力的另两个重要因素是种群生物量和温度。比较研究表明,从不适宜条件到适宜条件,蚯蚓消耗能力的理论范围约为6.378~27mg/(d·g)。能流研究表明,不同生境下,蚯蚓的各种生态效率变辐较大,即,毛增长效率:2.34%~9.92%,组织增长效率:28.95%~90.86%,同化效率:8.10%~34.27%,粪便率:65.73%~91.90%。赤子爱胜蚓的毛增长效率与同化效率约为该林区另一类主要土壤动物马陆的两倍,是帽儿山森林生态系统的重要分解者。因此,通过林木种类优化配置、温湿度条件的改变,可提高蚯蚓种群生物量及其分解能力,加快寒区厚积凋落物层的分解,加速林分更新。     

Feasibility of utilization of horse dung spiked filter cake in vermicomposters using exotic earthworm Eisenia foetida

This contribution reports the potential of vermicomposting technology in the management of horse dung (HD) spiked sugar mill filter cake (SMFC) using an epigeic earthworm Eisenia foetida under laboratory conditions. A total of six vermicomposters filled with different ratios of HD and SMFC were maintained for this study. The growth and fecundity of E. foetida was monitored for 12 weeks. Maximum growth was recorded in 90% HD+10% SMFC feed mixture containing vermicomposter. Earthworms' biomass gain and reproduction was favorably up to 50% HD+50% SMFC feed composition. Maximum cocoons were also recorded in 90% HD+10% SMFC feed mixtures, however increasing proportions of SMFC in different vermicomposters affected the growth and fecundity of worms. A significant decrease in C:N ratio and increase in total kjeldahl nitrogen, total available phosphorus and calcium contents was recorded. The heavy metals content was higher in the vermicompost obtained in all the reactors than initial feed substrates. Based on investigations it is concluded that vermicomposting could be an alternative technology for the management of filter cake if it is mixed in 1:1 ratio with horse dung.