Characterization of Genotoxin-Encoding Escherichia coli Isolated from Specific-Pathogen Free Cats with Impaired Fertility

2022 ◽  
pp. 109337
Author(s):  
Anthony Mannion ◽  
Whitney McGee ◽  
Yan Feng ◽  
Zeli Shen ◽  
Ellen Buckley-Jordan ◽  
...  
1980 ◽  
Vol 29 (3) ◽  
pp. 1073-1081
Author(s):  
Rodney D. Berg

Escherichia coli C25 maintained population levels of 10 9 to 10 10 per g of cecum and translocated to 100% of the middle mesenteric lymph nodes in gnotobiotic mice monoassociated with E. coli C25. Intragastric inoculation of these mice with the cecal contents from specific-pathogen-free mice reduced the population levels of E. coli C25 to 10 6 per g of cecum and completely inhibited translocation to the mesenteric lymph nodes. Intragastric inoculation with heat-treated, Formalintreated, or filtered cecal contents did not reduce the population levels of E. coli C25 or reduce the incidence of translocation of E. coli C25 to the mesenteric lymph nodes. Thus, viable bacteria apparently are required in the cecal contents inocula to reduce the population levels and the incidence of translocation of E. coli C25. Treatment with streptomycin plus bacitracin decreased the anaerobic bacterial levels in these gnotobiotic mice, allowing increased population levels of E. coli C25 and increased translocation to the mesenteric lymph nodes. E. coli C25 also translocated to the mesenteric lymph nodes of specific-pathogen-free mice treated with streptomycin and bacitracin before colonization with E. coli C25. The high cecal population levels of E. coli C25 in these antibiotic-decontaminated specific-pathogen-free mice apparently overwhelm any barrier to translocation exerted by the immunologically developed lamina propria of the specific-pathogen-free mice. Inoculation of gnotobiotic mice with a cecal flora also reduced the population levels of an indigenous strain of E. coli with a concomitant inhibition of translocation of the indigenous E. coli to the mesenteric lymph nodes. Thus, bacterial antagonism of the gastrointestinal population levels of certain indigenous bacteria, such as E. coli , by other members of the normal bacterial flora appears to be an important defense mechanism confining bacteria to the gastrointestinal tract.


1998 ◽  
Vol 35 (3) ◽  
pp. 178-190 ◽  
Author(s):  
S. B. Lockaby ◽  
F. J. Hoerr ◽  
L. H. Lauerman ◽  
S. H. Kleven

Six isolates of Mycoplasma synoviae, identified as WVU 1853, K1968, K1858, 92D8034, F10–2AS, and FMT, were compared for pathogenicity in broiler chickens. Specific-pathogen-free chickens were inoculated, in two groups of 20, with each isolate by footpad or eyedrop inoculation at 1 day of age and were examined at necropsy 7, 14, 28, and 42 days postinoculation. Specimens were taken for histopathology, culture, polymerase chain reaction assay, and hemagglutination-inhibition serology. Isolates were grouped according to pathogenicity on the basis of differences in lesion development and tissue distribution in the respiratory system, other viscera, and the skeletal system. K1968 (pathogenic) induced lesions in all sites examined in both the footpad and eyedrop inoculation groups. It was detected in all sites following footpad inoculation and in all sites except viscera following eyedrop inoculation. WVU 1853, K1858, and 92D8034 (moderately pathogenic) induced lesions and were detected in all sites following footpad inoculation. With eyedrop inoculation, lesions were identified only in upper and lower respiratory sites, and organisms were detected only in upper respiratory sites. F10–2AS (moderately pathogenic) was similar; however, footpad inoculation failed to induce visceral lesions or permit organism detection in any site. F10–2AS was detected in upper and lower respiratory tissues following eyedrop inoculation. FMT (mildly pathogenic) induced only upper respiratory lesions when either footpad or eyedrop inoculation was used, and detection was restricted to upper respiratory sites following eyedrop inoculation. These results are useful in comparative evaluations of the virulence of other M. synoviae isolates and form a basis for characterization of virulence factors of M. synoviae.


2020 ◽  
Vol 38 (1) ◽  
pp. 61
Author(s):  
Sruti Listra Adrenalin ◽  
Lynda Nugrahaning Imanjati ◽  
Ima Fauziah ◽  
Vinsa Cantya Prakasita ◽  
Sitarina Widyarini ◽  
...  

Avian pathogenic Escherichia coli (APEC) is a cause of colibacillosis in poultry, one of the respiratory disease that causes serious problems in the poultry industry. The APEC can cause high mortality and culling, decreased production, and high costs of treatment. Manifestations of colibacillosis are airsacculitis, perihepatitis, and pericarditis. The APEC serotypes that are widely identified in the field are O1K1, O2K1, and O78K80. Embryo lethality assay (ELA) is a method for determine the virulence of APEC serotypes. The aim of this study was to determine the virulence characteristic of APEC isolates. Five APEC serotypes O1K1, O2K1, O78K80, O157H7, and unknown serotype were used for ELA method by inoculated E. coli into chorioallantoic of specific pathogen free 12-days old embryos. Each group of 10 embryos, inoculated E. coli dose of 100-500 CFU/ 0,1 ml. Candling was carried out for 6 days (18-days old embryo) to determined the mortality and pathological lesions. The percentage of embryo mortality post-inoculated with APEC O1K1, O2K1, unknown serotypes were 100% (10/10), O78K80 serotype was 90% (9/10), and O157H7 serotype was 70% (70%). Lesions of all embryos were cranial and extremity hemorrhage. In this study, E. coli isolates had high virulence. 


2014 ◽  
Vol 52 (1) ◽  
pp. 120-131 ◽  
Author(s):  
L. Susta ◽  
M. E. B. Jones ◽  
G. Cattoli ◽  
S. Cardenas-Garcia ◽  
P. J. Miller ◽  
...  

Author(s):  
Michael C. Shen ◽  
Angela M. Preston ◽  
Merritt G. Gillilland III ◽  
John R. Erb-Downward ◽  
Bradley Todd ◽  
...  

2021 ◽  
Vol 8 ◽  
Author(s):  
Md Zulfekar Ali ◽  
Mohammad Moktader Moula ◽  
Zafar Ahmed Bhuiyan ◽  
Md Giasuddin ◽  
Hyun-Jin Shin

Chicken astrovirus (CAstV) and avian nephritis virus (ANV) are enteric viruses of poultry and have infected a wide range of poultry species worldwide, causing runting-stunting syndrome (RSS), which requires virus screening and results in serious economic damage. No confirmed cases have been reported from Bangladesh. In the present study, CAstV and ANV were monitored in Bangladesh. We monitored samples for CAstV and ANV and compared their genomic sequences to other reference strains. We found 8/31 flocks (25.8%) were positive for CAstV, 6/31 flocks (19.3%) had mixed infection of CAstV and ANV, and 1 flock (3.2%) was positive for ANV. Only ANV and a combination of CAstV and ANV were found in broilers and broiler breeders, but CAstV was found in all types of chickens. We isolated two of each from CAstV and ANV through specific pathogen-free chicken embryonated eggs via the yolk sac route. Phylogenetic analysis based on the ORF1b conserved region of CAstV and ANV suggested that the locally circulating strain was closely related to the strains isolated from India and Brazil. This report is the first molecular characterization of CAstV and ANV in Bangladesh. This study highlights that CAstV and ANV are circulating in Bangladeshi poultry.


2021 ◽  
Vol 12 ◽  
Author(s):  
Jingyi Liu ◽  
Xinjin Shi ◽  
Lu Lv ◽  
Kai Wang ◽  
Zhiwei Yang ◽  
...  

Fowl adenoviruses (FAdVs), which are distributed worldwide, have caused considerable economic losses to poultry farms. Co-infection with FAdVs and other avian pathogens has been reported previously. However, the pathogenicity of different serotypes of FAdVs causing co-infection remains unclear. Herein, strain HN from FAdV species C serotype 4 (FAdV-4) and strain AH720 from species E serotype 8a (FAdV-8a) were used to assess the pathogenicity of their co-infection in specific-pathogen-free (SPF) chickens. Compared with chickens infected with FAdV-4 alone, those co-infected with FAdV-4 and FAdV-8a showed similar clinical symptoms, mortality rates and degree of tissue lesions, and notably decreased viral loads of HN. Conversely, the viral loads of AH720 increased markedly in the co-infection group compared with that in chickens infected with AH720 strain alone. Increased viral loads of AH720 in the liver were suspected to contribute to the pathogenicity of chickens co-infected with the HN and AH720 strains. This was further investigated by histopathology and terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL) staining analyses. Collectively, these data indicated that co-infection with FAdV-4 and FAdV-8a suppresses the replication and proliferation of FAdV-4 but enhances the replication and proliferation of FAdV-8a in chicken liver. This study will provide valuable information for the further investigation of the interactions between FAdV-4 and FAdV-8a during co-infection.


1992 ◽  
Vol 38 (8) ◽  
pp. 774-778 ◽  
Author(s):  
Koji Nomoto ◽  
Teruo Yokokura ◽  
Kikuo Nomoto

We have previously reported that the lethal toxicity of 5-fluorouracil (5-FU) in specific-pathogen-free mice is due to an indigenous infection with Escherichia coli (K. Nomoto, T. Yokokura, Y. Yoshikai, et al. Can. J. Microbiol. 37: 244–247, 1991). In the present study, we demonstrate that nonspecific immunostimulation augments host resistance against the lethal toxicity of 5-FU in tumor-bearing mice. Intravenous administration of a preparation of heat-killed Lactobacillus casei (LC 9018), a nonspecific immunostimulant, at a dose of 20 mg/kg to BALB/c mice augmented their resistance against the lethal toxicity of 5-FU if the preparation was injected into the mice 10–40 days before administration of 5-FU. Injection of LC 9018 into BALB/c mice bearing Meth A fibrosarcoma also enhanced their resistance against the lethality of 5-FU. Systemic infection with E. coli was induced in all of the 5-FU-treated tumor-bearing mice 10 days or more after administration of the drug at a lethal dose of 500 mg/kg, and it was accompanied by an overgrowth of the bacteria in the intestine. Treatment of tumor-bearing mice with LC 9018 resulted in decreased rates of occurrence of systemic infection with E. coli and inhibition of overgrowth of the bacteria in the intestine after administration of 5-FU. A single administration of either LC 9018 or 5-FU significantly inhibited the growth of Meth A cells in vivo, and a combined antitumor effect was shown in the mice treated with both 5-FU and LC 9018. Key words: tumor-bearing mice, fluorouracil, nonspecific immunostimulation, indigenous infection, Escherichia coli.


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