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1.
本文对从内蒙古赤峰巴雅尔草业基地紫花苜蓿根部分离到的菌株 BYE27-2-5进行了致病性测定、形态学和rDNA-ITS 序列分析鉴定及生物学特性测定。结果表明,该菌菌丝生长、产孢和孢子萌发的最适温度分别为25,30和28℃;pH 值5.0~11.0均宜于菌丝生长,产孢最适 pH 8.0,孢子萌发最适 pH 7.0;光暗交替利于菌丝生长,光照利于产孢和孢子的萌发;孢子在相对湿度低于75%不萌发,高于95%萌发较快;葡萄糖蛋白胨培养基利于菌丝生长和孢子萌发,马铃薯蔗糖琼脂培养基利于产孢;碳源中葡萄糖利于菌丝生长和孢子萌发,蔗糖利于产孢;氮源中蛋白胨利于菌丝生长,酵母膏利于产孢和孢子萌发;菌丝致死温度为54℃(10 min),分生孢子的致死温度为48℃(10 min);根据其形态特征和 rDNA-ITS 序列分析结果,鉴定其为拟枝孢镰刀菌(Fusarium sporotrichioide )。  相似文献   

2.
本文对从内蒙古赤峰巴雅尔草业基地紫花苜蓿根部分离到的菌株BYE27-2-5进行了致病性测定、形态学和r DNA-ITS序列分析鉴定及生物学特性测定。结果表明,该菌菌丝生长、产孢和孢子萌发的最适温度分别为25,30和28℃;p H值5.0~11.0均宜于菌丝生长,产孢最适p H 8.0,孢子萌发最适p H 7.0;光暗交替利于菌丝生长,光照利于产孢和孢子的萌发;孢子在相对湿度低于75%不萌发,高于95%萌发较快;葡萄糖蛋白胨培养基利于菌丝生长和孢子萌发,马铃薯蔗糖琼脂培养基利于产孢;碳源中葡萄糖利于菌丝生长和孢子萌发,蔗糖利于产孢;氮源中蛋白胨利于菌丝生长,酵母膏利于产孢和孢子萌发;菌丝致死温度为54℃(10 min),分生孢子的致死温度为48℃(10 min);根据其形态特征和r DNA-ITS序列分析结果,鉴定其为拟枝孢镰刀菌(Fusarium sporotrichioide)。  相似文献   

3.
3种牧草根际平脐蠕孢形态和生物学特性   总被引:4,自引:3,他引:1  
自甘肃环县沟壑草地牧草根部常规组织分离获得特异平脐蠕孢、高粱平脐蠕孢和麦根腐平脐蠕孢,并对其生物学特性进行了研究。结果表明,3种平脐蠕孢在生物学特性上有明显差异,特异平脐蠕孢孢子萌发的温限为5~45℃,最适萌发温度为35℃,在45℃时萌发率仍高达85.1%;高粱平脐蠕孢孢子的萌发温限为5~40℃,最适萌发温度为15~30℃;麦根腐平脐蠕孢孢子的萌发温限为5~45℃,最适温度15~25℃,在45℃时萌发率仅为2.3%;不同pH值时特异平脐蠕孢孢子萌发率均较后2种高,且前者孢子萌发的最适pH值为5.59~6.47,后两者pH值均为6.47;土壤液等4种营养液对特异平脐蠕孢孢子萌发率在4h后有促进作用,对高粱平脐蠕孢在最初2h有促进作用,而对麦根腐平脐蠕孢则有抑制作用;3种菌萌发均需要液态水,但对光不敏感。  相似文献   

4.
为了探明造成江津龙华W?默科特叶缘黄化的致病真菌,通过组织分离、致病性和分子生物学鉴定,共分离鉴定出7株致病菌,其中4株属于链格孢属(Alternaria sp.);1株与喀斯特炭疽菌(Colletotrichum karstii)有99%的同源性;1株与蚕豆葡萄孢(Botrytis fabae)有99%的相似性;1株与蚕豆叶壳二孢菌(Ascochyta fabae CBS)、豌豆壳二孢菌(Peyronellaea pinodella)和Phoma pinodella有100%的同源性。此研究为江津龙华叶缘黄化的防控奠定基础。  相似文献   

5.
球孢白僵菌(Beauveria bassiana)可作为多种农业害虫的真菌杀虫剂。研究测定了不同温、湿度条件对球孢白僵菌Bb00菌株的营养生长、孢子萌发率以及对桑天牛(Apriona germari)幼虫致病力的影响。结果表明:25℃时该菌株营养生长最好,孢子萌发速度快且萌发率高,在此温度下菌株对桑天牛幼虫的致病力也最强;相对湿度为95%~100%时菌株的营养生长最好,随着相对湿度的增大孢子萌发速度、萌发率也增高,相对湿度100%时达到最高,此时被该菌株感染的桑天牛幼虫的死亡速度快,死亡率也最高。  相似文献   

6.
通过对实验室已构建的柱花草炭疽菌T-DNA突变体库中各转化子致病力的测定,获得致病力丧失突变菌株1869。对其进行PCR检测以验证T-DNA在1869基因组中插入情况,并测定观察其菌落直径、菌落形态及产孢量等生物学特性,利用TAIL-PCR克隆标记基因侧翼序列,采用生物信息学方法比对基因信息。结果表明,与柱花草炭疽菌野生型菌株CH008相比,突变菌株1869表现致病力丧失,菌落生长速率也显著低于野生型;然而,在分生孢子形态、产孢能力、孢子萌发率等方面与野生型并无明显差异。TAIL-PCR扩增得到T-DNA插入位点RB端序列467bp,LB端侧翼序列388bp,经两侧序列拼接比对,所得序列与Pac1同源性达到92%~96%,推测可能由于基因表达产物调节菌株对pH值的敏感性,从而影响了其致病过程。  相似文献   

7.
摘要:为了解芒果主产区炭疽菌株的致病力及分化情况。以台农1号为供试叶片,采用离体叶片针刺法,对2005-2013年采自海南、广西、广东、云南、四川以及美国夏威夷、泰国地区的112株芒果炭疽病菌进行致病力测定。结果表明,所有菌株均能引起台农1号叶片致病,采自不同地区、不同部位和不同品种来源的芒果炭疽菌致病性存在一定的差异。参照病菌致病性强弱分级标准,以接种5d的病斑平均直径作为标准,将供试菌株致病性划分为四类,其中强致病性菌株有30株,占26.78%;次强致病性菌株有27株,占24.11%;中致病性菌株有35株,占31.25%;弱致病性菌株有20株,占18.86%。  相似文献   

8.
2种麦冬炭疽病菌生物学特性的研究   总被引:7,自引:2,他引:5  
胶孢炭疽菌和黑线炭疽菌是麦冬炭疽病的病原菌.胶孢炭疽菌菌丝体生长、产孢和孢子萌发的最适温度都为28℃,黑线炭疽菌的分别为25,28和25℃.弱酸条件有利于2种炭疽菌菌丝体的生长和产孢,在pH值为4时产孢量都达到最大值,胶孢炭疽菌在pH值为7时孢子萌发率最大,黑线炭疽菌在pH值为8时达最大.光照处理对这2种病菌营养生长和产孢均无显著影响.供试碳源中果糖和葡萄糖有利于胶孢炭疽菌的菌丝体牛长,山梨糖和淀粉有利于其产孢;麦芽糖有利于黑线炭疽菌的菌丝体生长,淀粉有利于其产孢;氮源中有机氮有利于2种炭疽菌生长和产孢,化学氮源则表现抑制作用.胶孢炭疽菌和黑线炭疽菌的致死温度分别为55和50℃10 min.  相似文献   

9.
本试验利用常规方法研究了当归炭疽病菌(束状炭疽菌Colletotrichum dematium)的生物学特性和营养利用能力,为明确当归炭疽病的发生流行规律提供了依据。结果表明,菌落生长和孢子萌发最低温度和最高温度为10 ℃到35 ℃,最适为25 ℃;在pH 5~11间菌落可以生长,最适pH为11;在pH 8~11间产孢,最适pH为10,但中性有利于孢子萌发;该菌对碳氮源利用范围广,但甘露糖、D-半乳糖和氯醛糖抑制其生长;菌落生长和孢子萌发对光照不敏感;相对湿度95%以上分生孢子能萌发,水中萌发率显著高于其他湿度条件(P<0.05),蔗糖能够促进孢子的萌发,但马铃薯汁液抑制其萌发。  相似文献   

10.
本研究为初步明确引起青贮玉米(Zea Mays L.)叶斑病的蠕形菌种类,采集疑似病斑叶片样本,对病原菌进行分离纯化,形态特征观察,ITS-rDNA序列和GADPH基因序列系统发育分析及致病性测定。形态学和分子生物学鉴定结果表明分离得到的142株病原菌为3属6种真菌,其中麦根腐平脐蠕孢(Bipolaris sorokiniana)和玉米生平脐蠕孢(B.zeicola)为优势病原菌,分别为77株和48株;其次为大斑病菌(Exserohilum turcicum)9株,疣状弯孢(Curvularia verruculosa)2株,新月弯孢(C.lunata)3株,穗状弯孢(C.spicifera)3株。致病性测定发现麦根腐平脐蠕孢和玉米生平脐蠕孢对青海省8个主栽青贮玉米品种均有致病性,其余4种病原菌的致病性各有差异。本研究初步明确引起青贮玉米叶斑病的蠕形菌种类及其致病性,为后续开展病害诊断及其综合防控奠定了基础。  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

13.
14.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

15.
Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.  相似文献   

16.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

17.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

18.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

19.
The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.  相似文献   

20.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

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