Bacteria-infected turbots Scophthalmus maximus with septicaemia were examined between 2001 and 2004 in aspects of the conditions of disease occurrence, clinical syndromes and pathological changes. The phenotypic infor...Bacteria-infected turbots Scophthalmus maximus with septicaemia were examined between 2001 and 2004 in aspects of the conditions of disease occurrence, clinical syndromes and pathological changes. The phenotypic information of pathogenic bacteria was studied, including morphology, physiological and biochemical characteristics, and the mol% G+C of the DNA. In addition, representative strains (S010623-1, LH031120-1) were selected for molecular identification by partial 16S rRNA gene sequencing. The results show that the isolates (LH031120-1 to LH031120-6, HT040308-1 to HT040308-6, HT040620-1 to HT040620-6) from three farms were identified as Edwardsiella tarda. The isolates (S010610-1 to S010610-10, S010623-1 to S010623-20) from one farm were identified as Listonella anguillarum. We conducted studies on the pathogenicity of isolates by artificial infection, and revealed all infected groups in morbidity and mortality. The septicaemia infected turbot showed a syndrome similar to that of the naturally infected fish. Antibiotic sensitivity showed that of 37 antimicrobial agents, E. tarda was sensitive to 27 agents, and L. anguillarum was sensitive to 21 agents.展开更多
Background: The burden of neonatal septicaemia has remained high worldwide and even more severe in the developing countries like ours. Clinical manifestation is variable and non-specific thereby resulting in delay in ...Background: The burden of neonatal septicaemia has remained high worldwide and even more severe in the developing countries like ours. Clinical manifestation is variable and non-specific thereby resulting in delay in diagnosis. Blood culture which is the gold standard for diagnosis of neonatal septicaemia (NNS) has many drawbacks due to long waiting time for culture process, low yield, improper inoculation adding to the problem of late diagnosis. Haematological parameters have been utilized in rapid and early diagnosis of NNS and prompt treatment thus circumventing problems associated with drawbacks in blood culture. Objective: The study was to identify the common clinical features of neonatal septicaemia and haematological indices that were commonly utilized in rapid diagnosis of NNS, and also to determine their sensitivity, specificity, positive predictive and negative predictive value. Materials and Methods: The study was prospective and neonates that had clinical features suggestive of neonatal septicaemia were enrolled consecutively into the study. The patients were appropriately investigated including blood cultures, CSF cultures and urine among others, also blood sample for packed cell volume (PCV), total white cell count (TWBC), absolute neutrophil count (ANC), absolute platelet count (APC). Immature to mature neutrophil ratio (I/MNR), immature to total neutrophil ratio (I/TNR) and micro-ESR (erythrocyte sedimentation rate) was also done and analyzed. Results: The common clinical symptoms were fever 39.5%, poor feeding 33.6%, excessive cry 38.7%, difficulty in breathing 50.0%, yellowish skin 26.9%, while the common physical signs were hyper/hypothermia 41.1%, tachypnoea 41.2%, septic umbilical stump 64.0%, hepatomegally 37.3% and convulsions 42.0%. Blood culture yield was positive in 41.82% and mortality was as high as 28.00%, the incidence of NNS was 5.9/1000 live births. The haematological parameters as marker of NNS PCV, TWBC, ANC, APC, I/MNR, I/TNR and micro-ESR individually were statistically significant (P < 0.05), also their individual sensitivity, specificity, positive and negative predictive values were highly associated with neonatal septicaemia. However, when they were tested in combinations these markers of neonatal septicaemia had low sensitivity, specificity and their predictive values were weak in excluding NNS. Conclusions: The need for early and rapid diagnosis of NNS is pertinent, culturing of the appropriate specimens remains the only way to identify the aetiological organisms, but is associated with delay. Haematological indices are excellent markers of NNS and analysis is rapid and can easily be done in our laboratory settings, and when utilized efficiently, it would circumvent the delay associated with blood culture for long waiting period for the result, thereby reducing morbidity and mortality.展开更多
目的对一起养殖泥鳅病害进行发病情况、临床表现与病理变化、病原等方面的检验,旨在明确感染症的特征及相应的病原菌。方法随机取6尾病死泥鳅的肝及溃烂组织做细菌分离,对分离菌进行形态特征、生长表现、理化特性及代表菌株16S rRNA基...目的对一起养殖泥鳅病害进行发病情况、临床表现与病理变化、病原等方面的检验,旨在明确感染症的特征及相应的病原菌。方法随机取6尾病死泥鳅的肝及溃烂组织做细菌分离,对分离菌进行形态特征、生长表现、理化特性及代表菌株16S rRNA基因序列测定等方面的鉴定明确细菌种类。选择代表菌株制备成3×108CFU/ml的菌液,分别经腹腔、肌肉途径感染健康泥鳅,测定其致病作用;对鉴定后的菌株以琼脂扩散法(K-B)做对抗菌类药物的敏感性测定。结果被检病死泥鳅的下颌部肌肉溃烂,肝脏及脾脏肿胀等。从肝、溃烂组织均检出了纯一的同种细菌,经鉴定表明为气单胞菌属(Aero-monasKluyver and van Niel1936)的新种并定名为泥鳅气单胞菌(Aeromonals misgurnussp.nov.)。人工感染试验结果对泥鳅具有较强的致病作用,用37种抗菌类药物所做的药敏试验结果显示在不同株间无明显的敏感与耐药性差异。结论所检病例为细菌性败血感染症,其病原为泥鳅气单胞菌。展开更多
以自然患细菌性败血症的子二代中华鲟(Acipenser sinensis)幼鱼为研究对象,无菌操作从濒死病鲟体内分离到1株致病菌(zhx20120301)。结合传统细菌学鉴定及分子生物学鉴定方法,对其形态、生理生化特性、16S r DNA序列及系统发育分析等方...以自然患细菌性败血症的子二代中华鲟(Acipenser sinensis)幼鱼为研究对象,无菌操作从濒死病鲟体内分离到1株致病菌(zhx20120301)。结合传统细菌学鉴定及分子生物学鉴定方法,对其形态、生理生化特性、16S r DNA序列及系统发育分析等方面进行研究,研究结果显示这株细菌为维氏气单胞菌(Aeromomas veronii)。回归感染试验证实分离菌株具有较强的致病性,能导致健康杂交鲟(西伯利亚鲟Acipenser baerii♂×施氏鲟Acipenser schrenckii♀)死亡,并呈现与自然条件下相似的临床症状,且再分离菌株各种生理生化特性与原分离菌株相同。药敏试验结果表明该菌株对头孢氨苄、头孢唑啉、庆大霉素、四环素、强力霉素、氟苯尼考、多粘霉素B、恩诺沙星、氟哌酸和左氧氟沙星敏感。展开更多
基金Major State Basic Research Development Program (No. G1999012002)Science Technology Department Project of Hebei Province (No. 302431)
文摘Bacteria-infected turbots Scophthalmus maximus with septicaemia were examined between 2001 and 2004 in aspects of the conditions of disease occurrence, clinical syndromes and pathological changes. The phenotypic information of pathogenic bacteria was studied, including morphology, physiological and biochemical characteristics, and the mol% G+C of the DNA. In addition, representative strains (S010623-1, LH031120-1) were selected for molecular identification by partial 16S rRNA gene sequencing. The results show that the isolates (LH031120-1 to LH031120-6, HT040308-1 to HT040308-6, HT040620-1 to HT040620-6) from three farms were identified as Edwardsiella tarda. The isolates (S010610-1 to S010610-10, S010623-1 to S010623-20) from one farm were identified as Listonella anguillarum. We conducted studies on the pathogenicity of isolates by artificial infection, and revealed all infected groups in morbidity and mortality. The septicaemia infected turbot showed a syndrome similar to that of the naturally infected fish. Antibiotic sensitivity showed that of 37 antimicrobial agents, E. tarda was sensitive to 27 agents, and L. anguillarum was sensitive to 21 agents.
文摘Background: The burden of neonatal septicaemia has remained high worldwide and even more severe in the developing countries like ours. Clinical manifestation is variable and non-specific thereby resulting in delay in diagnosis. Blood culture which is the gold standard for diagnosis of neonatal septicaemia (NNS) has many drawbacks due to long waiting time for culture process, low yield, improper inoculation adding to the problem of late diagnosis. Haematological parameters have been utilized in rapid and early diagnosis of NNS and prompt treatment thus circumventing problems associated with drawbacks in blood culture. Objective: The study was to identify the common clinical features of neonatal septicaemia and haematological indices that were commonly utilized in rapid diagnosis of NNS, and also to determine their sensitivity, specificity, positive predictive and negative predictive value. Materials and Methods: The study was prospective and neonates that had clinical features suggestive of neonatal septicaemia were enrolled consecutively into the study. The patients were appropriately investigated including blood cultures, CSF cultures and urine among others, also blood sample for packed cell volume (PCV), total white cell count (TWBC), absolute neutrophil count (ANC), absolute platelet count (APC). Immature to mature neutrophil ratio (I/MNR), immature to total neutrophil ratio (I/TNR) and micro-ESR (erythrocyte sedimentation rate) was also done and analyzed. Results: The common clinical symptoms were fever 39.5%, poor feeding 33.6%, excessive cry 38.7%, difficulty in breathing 50.0%, yellowish skin 26.9%, while the common physical signs were hyper/hypothermia 41.1%, tachypnoea 41.2%, septic umbilical stump 64.0%, hepatomegally 37.3% and convulsions 42.0%. Blood culture yield was positive in 41.82% and mortality was as high as 28.00%, the incidence of NNS was 5.9/1000 live births. The haematological parameters as marker of NNS PCV, TWBC, ANC, APC, I/MNR, I/TNR and micro-ESR individually were statistically significant (P < 0.05), also their individual sensitivity, specificity, positive and negative predictive values were highly associated with neonatal septicaemia. However, when they were tested in combinations these markers of neonatal septicaemia had low sensitivity, specificity and their predictive values were weak in excluding NNS. Conclusions: The need for early and rapid diagnosis of NNS is pertinent, culturing of the appropriate specimens remains the only way to identify the aetiological organisms, but is associated with delay. Haematological indices are excellent markers of NNS and analysis is rapid and can easily be done in our laboratory settings, and when utilized efficiently, it would circumvent the delay associated with blood culture for long waiting period for the result, thereby reducing morbidity and mortality.
文摘目的对一起养殖泥鳅病害进行发病情况、临床表现与病理变化、病原等方面的检验,旨在明确感染症的特征及相应的病原菌。方法随机取6尾病死泥鳅的肝及溃烂组织做细菌分离,对分离菌进行形态特征、生长表现、理化特性及代表菌株16S rRNA基因序列测定等方面的鉴定明确细菌种类。选择代表菌株制备成3×108CFU/ml的菌液,分别经腹腔、肌肉途径感染健康泥鳅,测定其致病作用;对鉴定后的菌株以琼脂扩散法(K-B)做对抗菌类药物的敏感性测定。结果被检病死泥鳅的下颌部肌肉溃烂,肝脏及脾脏肿胀等。从肝、溃烂组织均检出了纯一的同种细菌,经鉴定表明为气单胞菌属(Aero-monasKluyver and van Niel1936)的新种并定名为泥鳅气单胞菌(Aeromonals misgurnussp.nov.)。人工感染试验结果对泥鳅具有较强的致病作用,用37种抗菌类药物所做的药敏试验结果显示在不同株间无明显的敏感与耐药性差异。结论所检病例为细菌性败血感染症,其病原为泥鳅气单胞菌。
