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Infectious bursal disease is an acute highly contagious disease affecting young chickens causing increased mortality and severe immunosuppression. Therefore, additional approaches together with vaccination are required to overcome its endemicity. Here, ten males Bosch rabbit of 3 months old (2-3 kg/weight) were used for production of IgG against IBDV. The produced rabbit IgGs were titrated using Passive Hemagglutination (PHA) and evaluated experimentally for their protection against vvIBDV challenge in commercial broiler chickens. Daily observation of clinical signs, mortalities and postmortem changes were recorded till 10 days post-infection. The spleen and bursa were collected for histopathological examination and cloacal swabs were collected to evaluate viral shedding by real time-PCR. The results indicated the effectiveness of the anti-vvIBDV IgG in protection against vvIBDV and in the reduction of viral shedding. These results suggested that IgG produced in rabbits may help in IBDV control and decrease its commercial economic losses. [ABSTRACT FROM AUTHOR]

The present study aimed to rule out the potential of multiple pathogens strains coexisting in a single sample and whether single colony could represent all microorganism present in the sample. A total of 20 samples (cloacal and tracheal) were collected from 10 apparently healthy quails in EL-Beheira governorate, Egypt. The samples were individually cultured on EMB agar. Eight out of 10 tracheal samples and 9 out of 10 cloacal samples were positive with green metallic sheen colonies. Fifteen colonies were individually collected from each plate of 8 tracheal samples and 20 colonies from each plate of 9 cloacal samples. As a result, 300 colonies were collected, with each colony being treated as a single sample. All 300 colonies were tested by Gram staining, motility test, biochemical tests, sugar fermentation and enzymatic reaction. The findings demonstrated that mixed infections were more common than single infections. Escherichia coli was the most frequently isolated organism (54.6%) followed by Enterobacter spp (22.3%), Klebsiella spp (11.6%), Citrobacter spp (9%), and Serratia liquefaciens (2.3%). Serological identification of E. coli (n=164) showed diversity of the serotypes among the samples derived from the same plate. Sixteen different serogroups in all the isolates were identified. Moreover, antimicrobial susceptibility of E. coli serotypes showed variable patterns with high sensitivity to gentamycin, doxycycline, ciprofloxacin, amikacin, tetracycline, and ampicillin indicating that these antimicrobials could be of great promise in combating E. coli infection in quails. These findings imply that diverse bacterial populations could be present in a single sample, making analysis of single colony from a bacterial culture plate insufficient to represent the actual population of pathogens. Further, quails could possibly play a significant role in harboring and spread of a variety of pathogens from the same or different strains. [ABSTRACT FROM AUTHOR]

In recent years there has been a growing interest in the marine environment as a promising source of new microorganisms with novel bioactive compounds against multi-drug resistant bacteria. The present study aimed to determine the antibacterial activity of marine Bacillus pumilus extract against Gram-positive bacteria such as Staphylococcus aureus, Bacillus subtilis and Enterococcus faecalis as well as Gram-negative bacteria such as Escherichia coli, Pseudomonas aeruginosa and Klebsilla pneumoniae. These bacteria were isolated from field samples using routine isolation methods. A disc diffusion assay was performed to determine the antibacterial effect of B. pumilus extract against the selected pathogens. The extract exhibited a broad inhibitory spectrum against all tested bacteria with inhibitory diameter ranging from 19 to 30 mm. These pathogens were further screened against 10 different antimicrobial discs. The result of antimicrobial susceptibility demonstrated that the tested organisms were resistant to many of the used antimicrobials with MAR index ranging from 0.3-0.6. Moreover, the antibacterial effect of B. pumilus extract was tested using the transmission electron microscope that revealed significant damage in all treated compared to untreated bacteria. These results suggest an antibacterial potential of B. pumilus extract against some pathogenic bacteria comparable to that of commercial antimicrobials and could be possibly used as a promising antibacterial agent. [ABSTRACT FROM AUTHOR]

In this study, the bacterium Sphingomonas sphingomonas 503 was isolated from water samples. One ml of water sample was cultured on MH broth for enriching bacterial growth then subcultured on MH agar plates till obtaining pure separate deep yellow-pigmented colonies (after four subcultures). The bacteria were cultured on blood agar and chromogenic agar, giving white hemolytic and green colonies, respectively. The bacterial isolates showed Gram-negative, polymorphic rods without special arrangement. The bacteria was identified by the VITEK Compaq® 2 system as Sphingomonas paucimobilis 503 and assayed for antibiotic susceptibility using Ampicillin, Ampicillin/sulbactam, Piperacillin/tazobactam, Cefazolin, Ceftazidime, Ceftriaxone, Cefepime, Meropenem, Amikacin, Gentamycin, Tobramycin, Ciprofloxacin, Levofloxacin, Nitrofurantoin, Trimethoprim/Sulfamethazole. This bacterium was sensitive to all tested antibiotics except Ceftazidime, which showed the highest MIC = 64, while the lowest MIC was that of Levofloxacin =0.12and Ciprofloxacin = 0.25. [ABSTRACT FROM AUTHOR]

Highly pathogenic avian influenza virus (HPAI) H5N1 has been isolated from many diverse species in Egypt. Here, we characterized the pathogenesis of a HPAI H5N1 isolated from naturally infected pigeons in Japanese quails. Our results showed that the pigeon virus was very pathogenic to quails; killing them within two days of intranasal inoculation. Further, phylogenetic analysis showed that the pigeon derived virus and the quail-derived viruses were close to viruses circulating in china and they segregated far from each other. [ABSTRACT FROM AUTHOR]

In the current study, we compared the efficiency of PCR detection to culture-dependent isolation of E. coli, as a model, from the liver and intestinal contents. Further, the incidence differences of E. coli isolation from the liver and intestine. Samples were collected from birds suffering from respiratory manifestation and/or diarrhea. Ninety E. coli isolates were recovered from 60 birds (52 intestinal and 38 liver samples) by bacteriological culture on selective broth and selective agar. PCR was performed using pho-A gene as a general marker for E. coli on DNA directly purified from the samples and assigned PCR (a). Negative PCR (a) samples were cultured on broth and another PCR was done, assigned PCR (b). Bacteriological isolation was more sensitive than PCR (a) indicating that inhibitors in the samples could have reduced or totally blocked the amplification capacity of PCR (a), which limited its diagnostic usefulness. PCR (b) was more sensitive than PCR (a) and more practical than bacteriological isolation. Detection of three virulence genes; iut-A, iss and tsh, showed genotypic variations of avian pathogenic E. coli (APEC) isolated from the liver and the intestine. In conclusion, an enrichment step results in more sensitive PCR than culture performed one. Further, general genes rather than virulence genes should be used as an indicator for E. coli detection in infected materials. [ABSTRACT FROM AUTHOR]

Two hundred and eighteen (218) fish samples collected from gills and muscles of Nile tilapia sold in two market regions in El-Behera governorate; Damanhour and Abou-humus, were examined for the presence of E. coli. Forty E. coli isolates (29 from gills and 11 from muscles) were identified by culture, biochemical analysis and PCR. Further, the isolates were studied for their antimicrobial susceptibility patterns using 9 antibiotics commonly used in the veterinary and medical fields . The highest resistances were by E. coli isolates from the gills against ampicillin, streptomycin, sulfamethoxazole-trimethobrim and tetracycline with 97.5%, 65%, 57% and 50%, respectively. While sensitivities were detected to Amikacin (97.5%), Ciprofloxacin (90%), Cefotaxime (67.5%) and Gentamycin (60%). Mult iple antibiotic resistances were detected in 95% (38/40) of the isolates. Higher MAR index was detected from E.coli isolates from the gills and 24 different resistance phenotypes were detected. PCR for the detection of the virulence genes; eaeA and stx2 and antimicrobial resistance genes; blaTEM, tetA(A), sul1 and aadA2 was performed. All tested isolates were 100% positive for the blaTEM gene. The eaeA, tetA(A) and Sul1 genes were detected in 83.3% (5/6) of the tested isolates, while the stx2 and aadA2 genes were detected in 50% only. These results collectively indicate that Nile tilapia in market can harbor pathogenic E. coli and act as a reservoir for mult i-resistance E. coli and facilitate its transmission and dissemination. [ABSTRACT FROM AUTHOR]

Highly pathogenic avian influenza (HPAI) H5N1 virus remains a public health threat and continues to cause outbreaks among poultry as well as human. Since its appearance, the virus has spread to numerous geographic areas and is now considered endemic in Egypt. Also widespread prevalence of H9N2 subtype in the Middle East region and its detection in Egypt in summer 2011 in poultry added another challenge to the Egyptian poultry industry as well as human health. Here, to evaluate the potential for avian to human transmission of avian influenza viruses H5 and H9, a serological study was conducted among 60 poultry workers and housewives and 143 participants randomly selected from Chest Hospital in Damanhour city in Behira governorate for determination of antibody titers against H5 and H9 avian influenza viruses by using hemagglutination inhibition assay. Further, participants were interviewed with a standardized questionnaire to assess the knowledge, attitudes, and practices regarding avian influenza infection. In addition, tissue samples from in contact poultry were assayed for virus detection by rapid test and positive samples were confirmed by real time RT- PCR. Our results showed some evidence of exposure to H5N1avian influenza virus with 3 (5%) poultry workers and 3 (2.1%) Chest hospital subjects having HI antibody titer of 1:160. All sera of poultry workers and housewives tested negative for H9. Only three poultry samples were positive for H5N1 virus. The level of community knowledge about AI disease was fair, but their practice and attitude were negative. Therefore, designing and implementing health educational programs about AI to improve the community practices should have the priority. Our findings support the low transmissibility of H5N1 to humans, but transmission to highly exposed persons cannot be excluded given that HI antibody titers of 1:80 and 1:40 were detected in some individuals. Prevalence of H9 antibodies was low, however, requires additional studies. [ABSTRACT FROM AUTHOR]

Highly pathogenic avian influenza (HPAI) H5N1 virus remains a public health threat and continues to cause outbreaks among poultry as well as human. Since its appearance, the virus has spread to numerous geographic areas and is now considered endemic in Egypt. Also widespread prevalence of H9N2 subtype in the Middle East region and its detection in Egypt in summer 2011 in poultry added another challenge to the Egyptian poultry industry as well as human health. Here, to evaluate the potential for avian to human transmission of avian influenza viruses H5 and H9, a serological study was conducted among 60 poultry workers and housewives and 143 participants randomly selected from Chest Hospital in Damanhour city in Behira governorate for determination of antibody titers against H5 and H9 avian influenza viruses by using hemagglutination inhibition assay. Further, participants were interviewed with a standardized questionnaire to assess the knowledge, attitudes, and practices regarding avian influenza infection. In addition, tissue samples from in contact poultry were assayed for virus detection by rapid test and positive samples were confirmed by real time RTPCR. Our results showed some evidence of exposure to H5N1avian influenza virus with 3 (5%) poultry workers and 3 (2.1%) Chest hospital subjects having HI antibody titer of 1:160. All sera of poultry workers and housewives tested negative for H9. Only three poultry samples were positive for H5N1 virus. The level of community knowledge about AI disease was fair, but their practice and attitude were negative. Therefore, designing and implementing health educational programs about AI to improve the community practices should have the priority. Our findings support the low transmissibility of H5N1 to humans, but transmission to highly exposed persons cannot be excluded given that HI antibody titers of 1:80 and 1:40 were detected in some individuals. Prevalence of H9 antibodies was low, however, requires additional studies. [ABSTRACT FROM AUTHOR]

Adaptive mutations and/or reassortments in avian influenza virus polymerase subunits PA, PB1, and PB2 are one of the major factors enabling the virus to overcome the species barrier to infect humans. The majority of human adaptation polymerase mutations have been identified in PB2; fewer adaptation mutations have been characterized in PA and PB1. Clade 2.2.1 avian influenza viruses (H5N1) are unique to Egypt and generally carry the human adaptation PB2-E627K substitution during their dissemination in nature. In this study, we identified other human adaptation polymerase mutations by analyzing phylogeny-associated PA mutations that H5N1 clade 2.2.1 viruses have accumulated during their evolution in the field. This analysis identified several PA mutations that produced increased replication by contemporary clade 2.2.1.2 viruses in vitro in human cells and in vivo in mice compared to ancestral clade 2.2.1 viruses. The PA mutations acted cooperatively to increase viral polymerase activity and replication in both avian and human cells, with the effect being more prominent in human cells at 33°C than at 37°C. These results indicated that PA mutations have a role in establishing contemporary clade 2.2.1.2 virus infections in poultry and in adaptation to infect mammals. Our study provided data on the mechanism for PA mutations to accumulate during avian influenza virus evolution and extend the viral host range. [ABSTRACT FROM AUTHOR]

Some avian influenza (AI) viruses have a deletion of up to 20 to 30 amino acids in their neuraminidase (NA) stalk. This has been associated with changes in virus replication and host range. Currently prevalent H9N2 AI viruses have only a 2- or 3-amino-acid deletion, and such deletions were detected in G1 and Y280 lineage viruses, respectively. The effect of an NA deletion on the H9N2 phenotype has not been fully elucidated. In this study, we isolated G1 mutants that carried an 8-amino-acid deletion in their NA stalk. To systematically analyze the effect of NA stalk length and concomitant (de)glycosylation on G1 replication and host range, we generated G1 viruses that had various NA stalk lengths and that were either glycosylated or not glycosylated. The stalk length was correlated with NA sialidase activity, using low-molecular-weight substrates, and with virus elution efficacy from erythrocytes. G1 virus replication in avian cells and eggs was positively correlated with the NA stalk length but was negatively correlated in human cells and mice. NA stalk length modulated G1 virus entry into host cells, with shorter stalks enabling more efficient G1 entry into human cells. However, with a hemagglutinin (HA) with a higher 2,6-linked sialylglycan affinity, the effect of NA stalk length on G1 virus infection was reversed, with shorter NA stalks reducing virus entry into human cells. These results indicate that a balance between HA binding affinity and NA sialidase activity, modulated by NA stalk length, is required for optimal G1 virus entry into human airway cells. [ABSTRACT FROM AUTHOR]