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101.
1981~1986年调查福建省崇安县水牛巴贝斯焦虫病,该病病原初步鉴定为牛巴贝斯焦虫Babesia boris(Babes,1988)。病原各类虫体形态所占比例分别为:单梨形虫体占37.21%,双梨形虫体占35.03%,椭圆形虫体占16.73%,环形虫体占7.67%,圆形虫体占1.34%和变形虫形虫体占2.01%。红细胞染虫数1~4个,多数1~2个。带虫红细胞平均直径5.25μm。梨形虫体平均长度1.98μm。虫体指数为1:1.04~2.76。红细胞染虫率x4.33%,S1.97%。虫体位于红细胞中部占78.55%,位子红细胞边缘占21.45%。双梨形虫体尖端排列形成钝角、锐角和直线分别为80.19%、14.15%和5.66%。 相似文献
102.
103.
【目的】从黄瓜叶片中筛选抗疫霉菌效果好的内生细菌并进行鉴定,为进一步研究黄瓜疫病的理
论探索及防治应用提供实验材料。【方法】以黄瓜叶片为实验材料筛选内生细菌,根据待检菌株的镜检特征、
革兰氏染色反应、菌落排列方式和菌落形态特征等进行初步筛选。采用平板对峙法和发酵液拮抗法实验对目标
内生细菌进行拮抗作用测定。通过 16S rDNA 序列测定及同源性分析,并构建系统发育树确定目标菌株种属。
【结果】初步筛选出 32 株内生细菌将其编号为 CL1~CL32,其中革兰氏阴性杆菌 10 株、革兰氏阳性杆菌 13
株、革兰氏阳性球菌 9 株,利用平板对峙法发现 8 株对掘氏疫霉菌有较强抑制作用的拮抗菌株,菌丝抑制率为
10.3%~54.3%,抑菌半径为 1~7 mm,对其中抑菌效果较好的 3 株菌株(CL7、CL9、CL15)进行发酵液拮抗实验,
结果显示其抑菌率分别为 54.4%、72.2%、63.3%。【结论】对掘氏疫霉菌具有较强抑制作用的 3 株内生细菌(CL7,
CL9、CL15)分别属于泛菌属 Pantoea sp.、假单胞菌属 Pseudomonas sp. 和葡萄球菌属 Staphylococcus sp.,其中
抑制效果最明显的为 CL9,即假单胞菌属 Pseudomonas sp.。 相似文献
104.
从 3批均以呼吸道症状和出血性胃肠炎为主要特征的死亡巨蜥中获得 3株嗜水气单胞菌。其培养性状及生化特性基本一致 ,均可产生β-溶血环。分离株对小鼠有较强的致病性 ,对PG、COS、VAN、CIP、NOR、CAR耐药。 3个菌株具有相同的菌体 (O)抗原血清型 ,该血清型与嗜水气单胞菌参考菌株 J1不同。应用丁胺卡那霉素和火焰消毒笼舍可有效防治上述菌株所导致的巨蜥疾病 相似文献
105.
甘肃加工型番茄叶果真菌病原鉴定及主要病害 总被引:1,自引:0,他引:1
经田间采集、分离培养、致病性测定,鉴定出13种加工型番茄真菌病原及病害。其中早疫病(Alternaria solani)、灰霉病(Botrytis cinerea)、叶霉病(Fulvia fulva)、斑枯病(Septoria lycopersici)、白霉病(Ramularia lycopersici)为甘肃省加工型番茄主要流行性病害,是制约甘肃省加工型番茄发展的主要病害。内丝白粉病(Leveillula brassicae)、柱隔孢菌(Ramularia lycopersici)侵染加工型番茄在国内外未见报道,属新病害。黑斑病(Alternaria brassicae)、果腐病(Fusarium moniliforme)、枯萎病(Fusarium oxysporium)、斑枯病(Septoria lycopersici)、煤污病(Cercospora fuligena)侵染加工型番茄在甘肃省属首次报道。 相似文献
106.
107.
Ken Steen Pedersen Markku Johansen ?ystein Angen Sven Erik Jorsal Jens Peter Nielsen Tim K Jensen Roberto Guedes Marie St?hl Poul B?kbo 《Irish veterinary journal》2014,67(1)
Background
The major indication for antibiotic use in Danish pigs is treatment of intestinal diseases post weaning. Clinical decisions on antibiotic batch medication are often based on inspection of diarrhoeic pools on the pen floor. In some of these treated diarrhoea outbreaks, intestinal pathogens can only be demonstrated in a small number of pigs within the treated group (low pathogen diarrhoea). Termination of antibiotic batch medication in herds suffering from such diarrhoea could potentially reduce the consumption of antibiotics in the pig industry. The objective of the present pilot study was to suggest criteria for herd diagnosis of low pathogen diarrhoea in growing pigs.Data previously collected from 20 Danish herds were used to create a case series of clinical diarrhoea outbreaks normally subjected to antibiotic treatment. In the present study, these diarrhoea outbreaks were classified as low pathogen (<15% of the pigs having bacterial intestinal disease) (n =5 outbreaks) or high pathogen (≥15% of the pigs having bacterial intestinal disease) (n =15 outbreaks). Based on the case series, different diagnostic procedures were explored, and criteria for herd diagnosis of low pathogen diarrhoea were suggested. The effect of sampling variation was explored by simulation.Results
The diagnostic procedure with the highest combined herd-level sensitivity and specificity was qPCR testing of a pooled sample containing 20 randomly selected faecal samples. The criteria for a positive test result (high pathogen diarrhoea outbreak) were an average of 1.5 diarrhoeic faecal pools on the floor of each pen in the room under investigation and a pathogenic bacterial load ≥35,000 per gram in the faecal pool tested by qPCR. The bacterial load was the sum of Lawsonia intracellularis, Brachyspira pilosicoli and Escherichia coli F4 and F18 bacteria per gram faeces. The herd-diagnostic performance was (herd-level) diagnostic sensitivity =0.99, diagnostic specificity =0.80, positive predictive value =0.94 and negative predictive value =0.96.Conclusions
The pilot study suggests criteria for herd diagnosis of low pathogen diarrhoea in growing pigs. The suggested criteria should now be evaluated, and the effect of terminating antibiotic batch medication in herds identified as suffering from low pathogen diarrhoea should be explored.Electronic supplementary material
The online version of this article (doi:10.1186/2046-0481-67-24) contains supplementary material, which is available to authorized users. 相似文献108.
109.
对虾病原菌2—5B菌株16SrRNA基因片段的克隆和序列测定 总被引:2,自引:0,他引:2
用引物PL1-PL2PCR扩增对虾病原菌-坎普氏弧菌2-5B菌株16SrRNA基因-1223bp的片段,采用pUC19质粒构建dT载体法完成该片段的克隆。部分序列测定及分析结果表明,该菌株与GenBank中坎普氏弧菌标准株序列之间同源性为96.94%。 相似文献
110.
MD Shah ALAM Shin-Ichi TESHIMA Manabu ISHIKAWA Shunsuke KOSHIO 《Fisheries Science》2002,68(3):509-516
ABSTRACT: To investigate the effects of disproportionate levels of dietary arginine and lysine on juvenile Japanese flounder Paralichthys olivaceus , growth performance and biochemical parameters were evaluated by feeding five test diets, comprising different levels of arginine and lysine, to triplicate groups of juveniles (initial bodyweight 1.85 g) for 40 days. Crystalline amino acids were supplemented to test diets to correspond to the amino acid pattern found in the whole body protein of the Japanese flounder, except for arginine and lysine. After the feeding trials, plasma arginine, lysine and urea levels, excreted ammonia-N, and liver arginase activity were analysed. Survival, specific growth rate, feed conversion efficiency, and apparent protein retention were adversely affected ( P < 0.05) by the deficiency in dietary arginine or lysine concentrations. An excess of either lysine or arginine in the diet did not depress growth when the diets contained adequate levels of either arginine or lysine, proving that there is no evidence for an arginine–lysine antagonism. Results for plasma arginine, lysine and urea levels, excreted ammonia, and liver arginase activity also demonstrated that Japanese flounder juveniles are not sensitive to excess dietary levels of lysine and arginine. 相似文献