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1.
摘要：以芒果枝枯病拟茎点霉菌（Phomopsis mangiferae Ahmad）为供试菌,采用菌丝生长速率法,考查了不同温度、pH、碳源、氮源、致死温度及时间、光照时间及不同芒果组织对病原菌菌丝生长的影响。结果表明：菌丝生长最适温度范围为25～30℃,以28℃生长最好;最适pH值为7;最佳碳源为麦芽糖,最佳氮源为蛋白胨、牛肉膏;致死温度为50℃处理30min或55℃处理20min;光照时间和不同芒果组织对菌丝生长影响不明显。  相似文献   

2.
从华中农业大学草坪草的狗牙根Cynodon dactylon上分离得到引起该草坪草黑斑病的病原菌,并对该病原菌进行了形态学观察、致病性测定、rDNA-ITS序列分析以及生物学特性的研究.研究结果表明:该病原菌在PDA培养基上培养7 d后菌落呈墨绿色,菌丝有隔,分生孢子有3个隔膜,中间两细胞较大,弯曲,两端细胞颜色较浅.孢子平均大小为24.94 μm×10.30 μm.其rDNA-ITS序列表明,分离的病原菌与Genbank中的Curvularia verruculosa的同源性是99%,结合形态学特征和致病性测定认为该菌为C.verruculosa.生物学特性研究表明,该菌丝在pH值5.0～9.0的PDA上均能生长,最适碳源为可溶性淀粉,最适氮源为KNO3.菌丝生长的致死温度为70 ℃ 15 min,孢子萌发的致死温度为75 ℃ 15 min.这是C.verruculosa引起狗牙根黑斑病的首次报道.  相似文献   

3.
紫花苜蓿根腐新病原-厚垣镰孢菌生物学特性研究   总被引：1，自引：0，他引：1  
针对紫花苜蓿根腐致病菌厚垣镰孢菌(Fusarium chlamydosporum)在不同温度、光照、p H和多种碳氮源条件下的生物学特性,采用菌饼法进行了测定,并对不同碳氮源下菌落产色素情况进行了连续观察。结果表明:该病原菌在5~40℃均可生长,最适温度为25℃;当p H 4.0~12.0时均能生长,最适宜p H为7.0;全黑暗条件有利于菌丝生长,菌丝生长最适碳源、氮源分别为山梨醇和蛋白胨,碳源氯醛糖及除蛋白胨以外8种氮源均不利于菌丝的生长。含不同碳氮源培养基可诱导菌丝产生不同色素,且颜色变化差异大,在不同的生长阶段,色素颜色也会发生变化。  相似文献   

4.
桑褐斑壳丰孢(Phloeospora maculans)是近几年鉴定的云南蚕区桑园发生桑褐斑病的主要病原菌之一。采用菌丝生长速率法研究不同培养基及碳源和氮源、p H值、温度、光照条件对该病原菌菌丝生长与产孢量的影响。结果表明,桑褐斑壳丰孢的菌丝适宜在PDA培养基和PDA+1%桑叶碎片培养基(简称PDA桑叶培养基)上生长,其中PDA桑叶培养基是最佳的产孢培养基;菌丝生长最佳培养基中的碳源和氮源物质分别是麦芽糖、蛋白胨,以可溶性淀粉为碳源的培养基产孢量最大,而在所有有氮源和无氮源物质的培养基上均不产孢;菌丝生长的最适培养基p H值为6~9,而p H 6时产孢量最大;在22~28℃培养条件下,菌丝生长最快,产孢量最大;连续黑暗条件适合菌丝生长和产孢;菌丝的致死温度条件为50℃水浴处理10 min。上述研究结果提示桑褐斑壳丰孢有很强的营养利用和环境适应能力。  相似文献   

5.
为研究不同碳源、氮源、碳氮比值及培养基初始pH值对少孢节丛孢菌菌丝生长的影响,采用10种碳源和8种氮源物质进行了试验,结果表明:在固体培养基上,少孢节丛孢菌菌丝生长的最适碳源和氮源分别是蔗糖和蛋白胨;在液体培养基内,最适碳源和氮源分别是红薯滤液和硫酸铵.当固体培养基中碳氮比为5:1、液体培养基中碳氮比为10:1时,茵丝生长最快.在初始pH值为3.7时,液体和固体培养基中的菌丝均不能生长;固体培养基中最适合的初始pH值范围是7.0～8.0,以pH值为7.5时菌丝的生长率最大;液体培养基中最适合的初始pH值范围是5.0～7.0,以pH值为7.0时菌丝生长最佳.说明不同的碳源、氮源、碳氮比及培养基初始pH值对少孢节丛孢菌菌丝生长率的影响是不同的.而且固体培养基和液体培养基中最适碳氮源、碳氮比、初始pH值也存在差异.  相似文献   

6.
草坪草红丝病与粉斑病是发生于世界范围内可危害多个草种的重要草坪草病害。本研究对我国首次报道的红丝病和粉斑病病原菌生物学特性进行了研究并在室内测定了14种杀菌剂对该两种病原菌的毒力。研究结果表明:红丝病和粉斑病病原菌菌丝适宜生长pH为5~7,最适生长pH为6,菌丝的致死温度为50 ℃水浴处理10 min。红丝病和粉斑病病原菌能够利用多种碳氮源,最适碳源和最适氮源分别为可溶性淀粉和L-谷氨酰胺。红丝病病原菌最适培养基为燕麦片煎液琼脂培养基(OMA);粉斑病病原菌最适培养基为马铃薯葡萄糖琼脂培养基(PDA)和马铃薯蔗糖琼脂培养基(PSA)。5%烯唑醇在14种供试杀菌剂中对红丝病病原菌和粉斑病病原菌毒力最高,其EC50值分别为0.113和0.282 mg/L;然而,15%甲霜灵·10%霜霉威毒力最低,其EC50值分别为121.522和214.532 mg/L。研究结果为深入了解病原菌的基础生物学及制定防治策略提供科学依据。  相似文献   

7.
东祁连山高寒草地土壤3种镰孢菌生物学特性的研究   总被引：1，自引：1，他引：0  
对东祁连山高寒草地土壤三线镰孢（Fusarium tricinctum）,木贼镰孢（F．equiseti）和尖镰孢（F．oxysporum）3种真菌的生物学特性进行了研究。结果表明,3种镰孢菌生物学特性有显著差异,三线镰孢和木贼镰孢菌丝生长温度为5-35℃,最适生长温度为20℃,尖镰孢的生长温度为15～35℃,最适生长温度为25℃;3种镰孢菌在pH值4～8．5均能生长,适宜pH值为7。三线镰孢和木贼镰孢的最适碳源为淀粉,最适氮源为氯化铵,尖镰孢的最适碳源为葡萄糖,最适氮源为蛋白胨。  相似文献   

8.
本研究从海南文昌椰子树上分离得到26株奇异根串珠霉菌，选取在PDA培养基上培养性状差异明显的3个分离株，进行了生物学特性研究。结果表明：3株分离株可以在15～35 ℃范围内生长和产孢，但对30 ℃以上高温的适应性有较大差异。3株分离株均可在查彼克培养基（Czapek）上生长和产孢。在供试碳源中，3株菌菌丝生长最佳碳源均为可溶性淀粉，BR2和GF924产孢最适碳源亦是可溶性淀粉，TR924产孢最适碳源为甘露醇；菌丝生长最佳氮源是氯化铵，BR2最适产孢氮源是硝酸钾，TR924和GF924在查彼克培养基（Czapek）上产孢量最大。3株分离株在pH4～11的范围内均能很好的生长和产孢。  相似文献   

9.
4种暖季型草坪草币斑病病原菌鉴定及其生物学特性   总被引：1，自引：0，他引：1  
章武  刘国道  南志标 《草业学报》2015,24(1):124-131
2011-2013年对海南省多个高尔夫球场及校园绿化草坪进行调查期间发现一种类似于草坪币斑病且可严重危害4种暖季型草坪草的草坪病害。根据科赫法则验证、形态学观察以及ITS序列分析的结果,确定引起海南省币斑病的病原菌为Sclerotinia homoeocarpa,这是我国首次报道S. homoeocarpa危害杂交狗牙根和地毯草。生物学特性研究表明: S. homoeoparpa生长的适宜温度为25~30℃,最适温度为28℃;适宜pH值为4~6,最适pH值为5;菌丝的致死温度为55℃水浴处理10 min;光照有利于菌丝生长。S. homoeoparpa能够利用多种碳氮源:碳源测试中,对可溶性淀粉利用率较高,对D-甘露醇和D-阿拉伯糖利用率较低;氮源测试中,病菌对硝酸铵、磷酸二氢铵的利用效果最佳,对脲利用效果最差。  相似文献   

10.
为明确紫花苜蓿不同镰刀菌的生长和产孢条件,以采自内蒙古不同地区紫花苜蓿根部的锐顶镰刀菌、茄病镰刀菌、木贼镰刀菌、变红镰刀菌、尖孢镰刀菌、燕麦镰刀菌、轮枝镰刀菌、层出镰刀菌、镰形镰刀菌、三线镰刀菌、F. virguliforme和芬芳镰刀菌为研究对象,测定其在不同温度、pH值、碳源和氮源培养条件下的菌落直径、产孢量及其菌丝致死温度。结果表明,不同种类镰刀菌的菌落生长和产孢均受温度、pH值、碳源和氮源的影响,不同菌种在同一培养条件下的菌落直径和产孢量存在显著性差异,同一菌种在不同培养条件下的菌落直径和产孢量也存在显著性差异。不同菌种的最佳培养条件各不相同,但其最适生长温度范围为20～30℃,最适产孢温度范围为15～30℃,最适生长和最适产孢pH值范围较广,最适生长碳源有蔗糖、可溶性淀粉、D-甘露醇、丙三醇和可溶性淀粉,最适产孢碳源有D-山梨醇、可溶性淀粉、羧甲基纤维素钠、D-半乳糖、D-果糖和丙三醇,最适生长氮源有牛肉膏、甘氨酸和硝酸钠,最适产孢氮源有牛肉膏、L-脯氨酸、硝酸钠、胰蛋白胨和硫酸铵。菌丝致死温度范围为50～70℃。在多数供试培养条件下,12个菌种中燕麦镰刀菌和芬芳镰刀菌菌落直...  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.
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   

14.
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   

15.
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   

16.
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   

17.
The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.  相似文献   

18.
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   

19.
The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.  相似文献   

20.
Infectious diseases have always been a terrible scourge for humans. The appearance of these plagues, as they were called without distinction, was generally connected to various conditions: asters, climatic changes or religious reasons. The concept of contagious, and then infectious, diseases came slowly. Variolation, i.e. transmission of ‘virulent’ matter to induce a natural disease and the immunity against it, was brought from Constantinople to England by Lady Montague, in 1721. This ‘variolation’ technique was also often performed in veterinary medicine against diseases like sheep-pox or pleuropneumonia. As ‘vaccination’ is the term generally accepted for ‘immunisation’, variolation can be the word designating such a technique. The second period of the history of immunisation began, in 1880, with the studies of Pasteur and his collaborators. A great number of bacterial vaccines were developed: dead, live but attenuated or only parts of pathogens. The viruses were produced in animals, then in eggs and at last, in tissue cultures. Second generation vaccines appeared with genetic engineering: recombinant vaccines, vector vaccines, nucleic acids vaccines, and markers vaccines, among others. These novel technologies can permit the development of new ones and improve the quality of the vaccines already existing.  相似文献   

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