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1.
分剐采集马属动物(马、骡)、反刍动物(牛、羊)的新鲜粪便,进行捕食线虫性真菌的分离培养,调查了捕食线虫性真菌在家畜粪便中的分布情况;并对分离到的捕食线虫性真菌做了详细的形态学观察,进行种属鉴定。结果表明:从上述家畜新鲜粪便中均分离出捕食线虫性真菌——梨形指环菌(Dactylaria pyriformis),但该菌株在不同家畜粪便中的分布情况不同,马属动物粪便的分出率为10.0%(骡粪:13.3%。马粪:6.7%);反刍动物粪便的分出率为26.7%(牛粪:23.3%,羊粪:30.0%);总分出率为18.3%。  相似文献   

2.
为了给动物线虫病的防治工作提供适应本地生存的候选捕食性真菌菌株,对新疆乌鲁木齐地区采集的土壤进行筛选,采用土壤撒布法,以秀丽隐杆线虫(Caenorhabditis elegans)作为诱饵线虫对土壤中的捕食性真菌进行分离鉴定,成功分离出具有捕食线虫功能的真菌1株。通过形态学观察,该菌捕食器官为黏性菌网,分生孢子无色,呈圆锥形,中央有一分隔,形态结构与节丛孢属相符。分子生物学分析显示,该分离株的ITS2基因序列与圆锥节丛孢菌(Arthrobotrys conoides)的同源性为99%~100%,判定该菌为圆锥节丛孢菌的新疆分离株。在实验室条件下,利用该菌株进行捕食线虫活力测定,结果发现该菌株在CMA培养基中对马圆形线虫三期幼虫的捕食率为97.47%,具有较强的捕食效率,可作为新疆地区动物线虫病生物防治工作的候选菌株。  相似文献   

3.
从自然界的土壤中分离到1株捕食线虫性菌物,在光学显微镜下对其生长过程中的形态学进行了观察。结果表明,该菌菌丝无色分隔;分生孢子梗直立不分枝,分生孢子呈纺锤形,生长期间不产生厚垣孢子;以粘性分枝捕食线虫。根据其形态结构特征,鉴定为捕食线虫性菌物——柱捕单顶孢菌(Monacrosporium cionopagum)。  相似文献   

4.
以山羊捻转血矛线虫第三期幼虫作为诱饵线虫,利用撒布分离法对新疆石河子地区土壤中的捕食线虫性真菌进行分离,并对所分离的捕食线虫性真菌进行了形态学及分子生物学鉴定.结果成功分离出了9株捕食线虫性真菌,其形态学符合少孢节丛孢菌.将分离株5.8S rDNA和ITS2基因序列与国内外已知少孢节丛孢菌菌株的对比分析,证明少孢节丛孢菌新疆分离株具有区域性特征,其捕食活性高于报道的菌株.分离出适合本地区生态环境的当地菌株对以后家畜线虫病的生物防控尤为必要.  相似文献   

5.
对捕食线虫性真菌——少孢节丛孢菌(Arthrobotrys oligospora)菌株体外粪便捕杀马寄生性线虫幼虫进行了研究。结果表明:菌株可以在体外粪便中发育并发挥其捕食作用。在实验室条件下,其对寄生性线虫第一、二期幼虫的作用与对第三期幼虫的作用相比较.捕获致死速度快。菌株对马粪便中线虫幼虫的杀虫率高达98.7%;与对照组相比有显著差异。而且加入粪便的分生孢子数量在达到一定阈值后,再加入分生孢子,则杀虫率不再增加。此结论对捕食线虫性真菌今后临床的应用具有实际指导意义。  相似文献   

6.
对捕食线虫性真菌——少孢节丛孢菌(Arthrobotrys oligospora)菌株进行了临床杀家畜寄生性线虫幼虫作用的研究。结果表明:培养的少孢节丛孢菌分生孢子经口饲喂动物后,对粪便中线虫幼虫的杀虫率分别可达96.3%(羊)、96.5%(牛)和97.4%(马)。说明少孢节丛孢菌菌株分生孢子可通过家畜消化道,并保持了其捕食寄生性线虫的能力。研究结果为捕食线虫性真菌的临床应用奠定了重要基础。  相似文献   

7.
对捕食线虫性真菌——少孢节丛孢菌A1分离株(Arthrobotrys oligospora A1)的18S rDNA基因序列进行了研究。结果表明:其18S rDNA全基因序列为1769bp,在进化树上与同种国外分离株A.oligospora var oligospora 1最为接近,同源性为94.7%。这与二者都具有捕食性结构—菌网的特点相一致。证实捕食线虫性真菌的捕食性结构与捕食线虫性真菌种系发生有关。从少孢节丛孢菌3个分离菌株(Arthrobotrys oligospora A1、A.oligospora 1、A.oligospora2)的进化树及同源性来看。不同国家地区的丛孢菌属(Arthrobotrys)分离株确实存在差异。  相似文献   

8.
为研究新疆地区捕食线虫性真菌的生物活性,本实验采用玉米粉琼脂培养基(CMA)培养分离自新疆不同地区的捕食线虫性真菌,通过对分离株纯培养物的形态学观察和18S rDNA基因序列分析,鉴定4株少孢节丛孢菌,分别命名为XA3、XA6、XD1和XD4。18S rDNA基因遗传进化分析表明,XA3、XA6、XD1和XD4新疆分离株之间同源性较高,与GenBank登录的少孢节丛孢菌CBS289.82株同源性最高,分别为99.6%、99.5%、99.1%和98.9%,与形态学鉴定结果一致。捕食线虫活性测定试验表明,4个分离株在CMA中的捕食率为92.8%~97.6%;体外对绵羊粪便中线虫幼虫的捕食率为90.7%~95.4%,均具有很强的捕食活性。本研究为研究绵羊消化道线虫生物防控制剂奠定基础。  相似文献   

9.
捕食线虫性真菌-少孢节丛孢菌理化特性研究   总被引:1,自引:0,他引:1  
研究了捕食线虫性真菌一少孢节丛孢菌(Arthrobotrys oligospora)的染色特性、分生孢子对外界理化因素的抵抗力以及菌丝对线虫第三期幼虫的吸引作用等。结果表明少孢节丛孢菌用革兰氏、瑞氏、姬姆萨氏液染色都能很好的着色;分生孢子对高温敏感,对抗生素不敏感,高浓度的氢离子或氢氧根离子能杀死分生孢子:但分生孢子耐低温,因此可用低温冷冻法保存捕食线虫性真菌分生孢子,其方法简便易行。首次解决了国内外在捕食线虫性真菌菌种保存中的难题。研究显示菌丝对线虫第三期幼虫无明显吸引力。  相似文献   

10.
为获取理想的生物防治捕食线虫性真菌菌株,达到利用自然天敌有效控制家畜寄生性线虫病的目的,作者利用低能氮离子注入诱变捕食线虫性真菌——少孢节丛胞菌(Arthrobotrys oligospora)的分生孢子,测定分生孢子萌发后菌丝的生长速度、产孢能力及菌株对线虫幼虫的捕食率,筛选正突变株。结果表明,低能氮离子束具有诱变少孢节丛孢菌的潜能,诱变后的1株少孢节丛孢菌的生长速度、产孢量和对线虫幼虫的捕食率呈现出了正突变效果。  相似文献   

11.
捕食线虫性真菌的分离培养技术与形态学   总被引:19,自引:3,他引:16  
分离培养捕食线虫性真菌的最佳培养基为 0 .4g/ L 玉米粉琼脂培养基 (CMA) ;0 .4g/ L 玉米粉液体培养基可作为保存菌种培养基。在分离培养过程中 ,必须加入活的线虫第 3期幼虫 ,以诱导菌株产生捕食性器官——菌环、菌网 ,并与其他真菌鉴别。捕食线虫性真菌有菌丝和孢子 2种形态 ,其发育时期不同。本试验分离的少孢节丛孢菌(Arthrobotrys oligospora) ,菌丝发达 ,无色有隔 ,隔距不等 ;分生孢子梗直立不分支 ,分生孢子围绕着分生孢子梗呈轮状排列 ,似梅花瓣状 ,2层以上 ;孢子呈倒卵形 ,丰满无色 ,有横隔 ,游离端大而钝圆 ,梗端小而稍尖。  相似文献   

12.
Three hundred and eighty-four samples of leaf litter, soil, faeces from domestic and game animals, compost and aqueous cultures of infective nematode larvae contaminated with unidentified fungi were plated out on water agar, baited with pure infective larvae of Haemonchus contortus, incubated and examined for the presence of nematophagous fungi. Duddingtonia flagrans was isolated from five samples, and 73 samples were positive for other nematophagous fungi.  相似文献   

13.
Biological options for nematode parasite control are being sought, as the long-term efficacy of conventional anthelmintics comes increasingly under threat from drug-resistant parasites. Three biological methods with the potential to reduce pasture contamination by parasitic nematode larvae were examined: (a) killing of larvae developing in dung by nematophagous fungi; (b) removal of dung through earthworm ingestion; (c) burial of dung in soil as might occur through the action of dung beetles. Field trials with the test bio-control agents were carried out in autumn and spring by adding dung from sheep infected with Ostertagia (Teladorsagia) circumcincta to pots of ryegrass/white clover. The factorial treatment structure included five fungal treatments (individual applications of Duddingtonia flagrans, Monacrosporium gephyropagum and Harposporium helicoides, a combination of all the three fungi together and an untreated control), two dung burial treatments (dung buried or deposited on the soil surface) and two earthworm treatments (earthworms present or absent). D. flagrans and H. helicoides, individually or in combination, reduced recovery of infective stage larvae in experiment 1, while only H. helicoides reduced recovery in experiment 2. In both the experiments, dung burial increased the total number of larvae recovered, while the number of infective larvae were reduced by the action of earthworms. Increased recovery following burial, along with the fact that larvae moved rapidly from soil onto herbage, suggests that soil may provide a protective reservoir for infective larvae infesting herbage.  相似文献   

14.
Laboratory experiments were designed to study the influence of temperature, concentrations of nematodes, oxygen tension, light, and nutrient levels, on the induction of nematode-trapping hyphal nets in the predacious fungus Arthrobotrys oligospora. When induced by infective Ostertagia ostertagi larvae, a maximum number of nets was produced at 20 degrees C, at which temperature nets in surplus were produced at larval concentrations up to 1,000 larvae per cm2. A. oligospora did not produce nets in an anaerobic atmosphere containing 21% CO2 (v/v), and net induction was suppressed to a certain degree by exposure to light. The composition of the medium had an important influence on the saprophytic growth and the net-forming capability of A. oligospora as a maximum number of nets was induced at a relatively low concentration of corn meal supporting the relatively sparse mycelium. It was shown that a proportion of trapping nets in A. oligospora maintained their trapping potential for more than 7 weeks when the temperature was below 25 degrees C. Induction of nematode-trapping organs in A. oligospora is discussed in relation to control of infective nematode parasite larvae in cow pats.  相似文献   

15.
The analysis of the capability of the nematode trapping-fungus Duddingtonia flagrans to adapt to the cyathostomin egg-output in horses was evaluated. Fecal samples from 196 pasturing autochthonous Pura Raza Galega horses were collected from the rectum and then divided according to the egg-output into three groups: ≤ 300, 310-800 and >800 eggs per gram feces. Four doses of chlamydospores (0.1, 0.2, 0.4 and 0.8 × 10(6)/100g feces) were directly spread onto fecal pats on the ground, remaining one without treatment as control. Fecal pats confirmed the presence of gastrointestinal nematode larvae belonging to strongylid cyathostomins (Cyathostomum and Gyalocephalus spp). An overall 94% (95% CI 91, 97) percentage of reduction was obtained, and an increase in the activity of the trapping-fungi simultaneously to the rising in the number of cyathostomin eggs and larvae in the coprocultures was detected. A significantly highest reduction of the cyathostomin L3 in the coprocultures with more than 800 EPG was found, which indicates that Df trapping activity is larvae nematode density-dependant. The present research showed the high biological activity of D. flagrans against nematode larvae can adjust to the cyathostomin egg-output, and underlines its efficacy as a practical method for the control of these parasites in grazing horses.  相似文献   

16.
For oral applications, biocontrol of animal parasitic nematodes in ruminants, ion beam implanted nematode-trapping fungi must have the capacity to survive the passage through the digestive tract and be efficient in reducing infective larvae of nematodes in the faeces.Ion beams induced mutation in the spores of nematode-trapping Arthrobotrys oligospora. Mutants with genetic stability were bred. The fungi were cultured in bottles with corn kernels as growth media, and spores of different doses were, respectively, administered orally to each group of sheep naturally infected with gastrointestinal nematodes. The control group did not receive fungi. The faeces of these experimental animals were collected and faecal cultivations carried out. The fungal germination, growth, reproduction and predation of livestock parasitic nematode larvae were tested in laboratory. The efficacy of an A. oligospora N mutant in nematode-trapping larvae after passage through the digestive tract of sheep was tested. The results indicated that the ion beam implantation induced mutation of the nematode-trapping fungi is a positive mutation. The mutant spores through the digestive tract of sheep can kill livestock parasite nematode larvae in vitro. These results indicate the potential of the A. oligospora N mutant as a biological control agent for sheep nematodes.This study showed that such biotechnology could be explored for improving the effectiveness of the use of fungal infections to control livestock parasitic nematodes. This work represents the first application of nematode-trapping fungi in eukaryotic microorganisms.  相似文献   

17.
Gastrointestinal nematodes are of concern in sheep production because of production and economic losses. Control of these nematodes is primarily based on the use of anthelmintic treatment and pasture management. The almost exclusive use of anthelmintic treatment has resulted in development of anthelmintic resistance which has led to the need for other parasite control options to be explored. The blood sucking abomasal parasitic nematode Haemonchus contortus causes severe losses in small ruminant production in the warm, humid sub-tropic and tropics. This study evaluated the effectiveness of a nematode trapping fungus, Duddingtonia flagrans, in reducing availability of parasitic nematode larvae, specifically H. contortus, on pasture. Chlamydospores of D. flagrans were mixed with a supplement feed which was fed daily to a group of crossbred ewes for the duration of the summer grazing season. A control group was fed the same supplement feed without chlamydospores. A reduction in infective larval numbers was observed in fecal cultures of the fungus-fed group. Herbage samples from the pasture grazed by the fungus-fed group also showed a reduction in infective larvae. There were no significant (P > 0.05) differences in overall fecal egg count, packed cell volume or animal weight between fungus-fed and control groups. Tracer animals were placed on the study pastures at the end of the study to assess pasture infectivity. Although tracer animals were only two per group, those that grazed with the fungus-fed group had substantially reduced (96.8%) nematode burdens as compared to those from the control group pasture. Results demonstrated that the fungus did have activity against nematode larvae in the feces which reduced pasture infectivity and subsequently nematode burdens in tracer animals. This study showed that D. flagrans, fed daily to grazing ewes, was an effective biological control agent in reducing a predominantly H. contortus larval population on pasture.  相似文献   

18.
Consequences of nematode infections due to Haemonchus contortus are a serious constraint for the sheep industry worldwide. Development of anthelmintic resistance and increasing concern about the impact of anthelmintic use dictate the need of alternative control. Such an alternative is using the nematode trapping fungus Duddingtonia flagrans to reduce infective larvae levels on pasture. Two trials were conducted to determine the effect of D. flagrans in reducing infective larvae (predominantly H. contortus) in feces. The first trial determined the dose effect of D. flagrans in reducing infective larvae in feces. Eighteen ewes were dewormed to remove existing infections and randomly assigned to six treatment groups: 5 x 10(4), 1 x 10(5), 2.5 x 10(5), 5 x 10(5), 1 x 10(6) or no (control) spores of D. flagrans per kg of body weight mixed in their feed for 7 days. Fecal samples were collected daily from these and from infected donor ewes. Feces from individual-treated ewes were mixed with equal amounts of donor ewe feces, theoretically approximating oral dose spore concentrations of 2.5 x 10(4), 5 x 10(4), 1.25 x 10(5), 2.5 x 10(5), 5 x 10(5) and no spores, and were cultured. Across dosages and during the 7 days of fungus feeding, percent reduction of infective larvae ranged from 76.6 to 100.0%. The second trial determined the effect of D. flagrans at the dose of 10(5) spores per kg body weight on reducing infective larvae in feces from naturally infected lambs. Twenty lambs were randomly assigned to either treatment or control groups based on fecal egg count. Treatment lambs were fed spores mixed in feed for 7 days. Feces were collected daily and cultured. During the 7 days of fungus feeding, the percent reduction of infective larvae ranged from 82.8 to 99.7%. Results of these trials demonstrated that the nematode trapping fungus D. flagrans was highly effective in reducing infective larvae in sheep feces and should be considered as a biological control agent for integrated nematode control programs.  相似文献   

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