The Susceptibility of Japanese Quails to the Infection with Chicken Originated NewCastle Disease Virus

Newcastle disease virus (NDV) caused an outbreak among commercial broiler chickens in the educational farm of Faculty of Agriculture, Assiut University-Egypt. Its velogenicty was characterized by Intracerebral pathogenicity index (ICPI) of 1.65. The outbreak raised concerns regarding the role of quails as a neighboring bird to the broiler chickens in the affected farm in transmission of this virus to chickens. 35 days old quails were infected oculo-nasal with velogenic strain of Newcastle disease virus accompanied with chickens were in contact with these infected quails to determine the role of quails in the epidemiology of ND infection. Hemagglutination inhibition (HI) antibodies were measured for assessment of antibody response as well as oro-pharynx swabs were used for detection of the virus shedding. The susceptibility of quails to NDV infection was more resistant than that were observed in chickens. 6.6-13.3% of challenged non-vaccinated quails were died in contrast to 80-100% mortality in experimentally infected chickens till the end of experiment 3 weeks after challenge. Up to 13.3% of infected quails exhibited general clinical signs in contrast to 100% of non vaccinated chickens shown clinical signs were primarily respiratory. Infected quails could excrete infectious virus from the oro-pharynx for a shorter period than that observed with infected in-contact chickens in special to the vaccinated groups the shedding was reduced significantly either in quails and chickens. The results confirmed that some of the naturally occurring NDV virulent strains can cause the disease in quails but in a mild form, and that quails play an important role in the epidemiology of ND and its transmission to chickens causing heavy economic losses. These results under- score the need to develop new vaccine strategies for use in quails to protect birds from both disease and infection to reduce virus shedding and its spreading

Enhancement of Antimicrobial Sensitivity of Salmonella and Escherichia coli Strains Isolated from Chickens Using Silver Nanoparticles in Assiut Governorate

Before the era of complete resistance to antibiotics due to their extensive use in poultry farms, new strategies were discovered, one of them was the use of nanoparticles to enhance the action of antibiotics. Therefore, this study was carried out to find out the antibacterial effect of silver nanoparticles (AgNPs) either separately or in combination with antibiotics. The obtained data showed the antibacterial activity of AgNPs against the tested Escherichia coli and Salmonella strains with MIC level of 0.85 µg/mL. Synergistic effects of AgNPs with antibiotics against E. coli revealed two-fold drop in MIC of ciprofloxacin and amoxicillin. Meanwhile, there was three-fold drop in MIC of gentamicin, cefotaxime and neomycin. Significant finding was observed in the case of the synergism of AgNPs with amoxicillin and gentamicin, the examined E. coli O2 resistant to amoxicillin and gentamicin became sensitive when the antibiotics were combined with AgNPs. It could be concluded that AgNPs can be easily produced by Rosemary aqueous extracts as low-cost, eco-friendly method for generating AgNPs. New generations of bactericidal compounds containing AgNPs could be successfully used in poultry farms for prevention and treating E. coli infections

Evaluation of The Living Escherichia coli-O78 Deleted aroA Vaccine Against Homologous and Heterologous E. coli Challenge in Broiler Chickens

To determine whether the immunization using commercially available living Escherichia coli-O78 aroA deleted vaccine (Poulvac®E. coli) is protective against APEC challenges or not. Ninety chicks were divided into six groups (15 birds/each); two groups were vaccinated at day 1 by spray and drinking routes then challenged intratracheally with homologous E. coli O78 at day 21, the other two groups were similar to the previously mentioned groups but challenged with heterologous E. coli O1 in parallel with the four challenged-vaccinated groups there were two positive control (challenged-not vaccinated) groups; one challenged with O78 and the other one with O1 at day 21 using intratacheal route. The best obtained results were recorded to the vaccinated-challenged group with the homologous strain and vaccinated by spraying method which exhibited decreases in organ lesion scores in comparison to the other groups (non-vaccinated challenged chickens and groups of chickens either homologous challenged-vaccinated through drinking water or heterologous challenged-vaccinated groups). These findings suggest that vaccine is a suitable for minimizing lesion scores against homologous challenge using spraying method that could lead to minimizing the time for treatment and cases of condemnation in processing plants

The Susceptibility of Japanese Quails to the Infection with Chicken Originated NewCastle Disease Virus

Newcastle disease virus (NDV) caused an outbreak among commercial broiler chickens in the educational farm of Faculty of Agriculture, Assiut University-Egypt. Its velogenicty was characterized by Intracerebral pathogenicity index (ICPI) of 1.65. The outbreak raised concerns regarding the role of quails as a neighboring bird to the broiler chickens in the affected farm in transmission of this virus to chickens. 35 days old quails were infected oculo-nasal with velogenic strain of Newcastle disease virus accompanied with chickens were in contact with these infected quails to determine the role of quails in the epidemiology of ND infection. Hemagglutination inhibition (HI) antibodies were measured for assessment of antibody response as well as oro-pharynx swabs were used for detection of the virus shedding. The susceptibility of quails to NDV infection was more resistant than that were observed in chickens. 6.6-13.3% of challenged non-vaccinated quails were died in contrast to 80-100% mortality in experimentally infected chickens till the end of experiment 3 weeks after challenge. Up to 13.3% of infected quails exhibited general clinical signs in contrast to 100% of non vaccinated chickens shown clinical signs were primarily respiratory. Infected quails could excrete infectious virus from the oro-pharynx for a shorter period than that observed with infected in-contact chickens in special to the vaccinated groups the shedding was reduced significantly either in quails and chickens. The results confirmed that some of the naturally occurring NDV virulent strains can cause the disease in quails but in a mild form, and that quails play an important role in the epidemiology of ND and its transmission to chickens causing heavy economic losses. These results under- score the need to develop new vaccine strategies for use in quails to protect birds from both disease and infection to reduce virus shedding and its spreading

Virulence Genes Content and Antimicrobial Resistance in Escherichia coli from Broiler Chickens

A total of 121 E. coli strains were isolated from broiler chickens (96 extraintestinal pathogenic (ExPEC) strains from diseased broiler chickens and 25 avian fecal E. coli (AFEC) from healthy ones). Ten of the isolates (6 from diseased chickens and 4 from healthy birds) were serogrouped and 25 were examined for 4 virulence markers (tsh, papC, colV, and iss genes) as well as for their antimicrobial resistance. Five strains were nontypable and the rest were serotyped as follows: O86:K61 (2/5), O78:K80 (1/5), and O128:K67 (1/5) were recovered from diseased chickens, while O111:K58 strain (1/4) was isolated from healthy ones. The iss gene was found in 72.2% of the examined ExPEC strains in contrast to zero percentages (0%) in the AFEC strains, which may serve as a good marker for distinguishing APEC and its knocking out may help in creation of candidate vaccine that may prove sucess in elimination of infections in broiler chickens. Antimicrobial resistance patterns revealed a complete resistance to gentamicin, pefloxacin, amoxicillin, and enrofloxacin among examined strains followed by varying degrees of resistance for the rest of tested agents. The highest resistance was recorded against norfloxacin, in 24 isolates (96%), in contrast to the lowest resistance was recorded against colistin sulphate, in 14 strains (56%). These findings suggest the need for the prudent use of antimicrobials with broiler chickens and act as a warrant for the possibility of avian sources to transmit these resistant isolates to humans

The ameliorating effect of some immune-stimulants on bursal and tracheal lesions of broiler chickens challenged with ND virus

Abstract Background Nowadays, immuno-stimulants have great importance in improving the immune system and minimising the effect of infectious diseases in poultry flocks. This study was designed to demonstrate the impact of using different immune-stimulants on the reduction of the harmful implications of virulent ND virus through evaluation of histopathological lesion scores on bursa and trachea of vaccinated and infected broiler chickens with Newcastle disease (ND). Results Eighty Ross breed broiler chicks at the age of 1 day were randomly divided into four groups, each group formed of 20 birds. Group I was vaccinated against AI, ND and IBD and used as a control. Groups II, III and IV were immunised as group I and also had immuno-stimulant supplement, Imutrix® (oregano oils plus ß-glucan), Evit liquid® (Vitamin E plus selenium) and Immunair 17.5 (Propionibacterium acnes and E. coli lipopolysaccharides), respectively. All groups were experimentally infected with virulent ND virus at the age of 28 days. The morbidity rates for groups I, II, III and IV were 15%, 5%, 5% and 10% respectively. Histopathological examination of bursa revealed hyperplasia of lymphoid follicles in group I which became more evident in groups II, III and IV. Group III showed hyperplasia of tracheal epithelium with lymphocytes and heterophils infiltration in lamina propria. CD79A-positive cells were significantly higher in bursa of group III in comparison to other groups during an immunohistochemical examination. Conclusion It was concluded that Evit liquid® (vitamin E plus selenium) supplementation might have potent immunomodulatory effect in chickens

Pasteurella multocida in backyard chickens in Upper Egypt: incidence with polymerase chain reaction analysis for capsule type, virulence in chicken embryos and antimicrobial resistance

The prevalence of Pasteurella multocida strains among 275 backyard chickens from different regions of Upper Egypt was studied. A total of 21 isolates of P. multocida were recovered in 21 out of 275 chickens tested (7.6%) and were confirmed using phenotypic characterisation. Somatic serotyping of the 21 isolates resulted in 12 isolates being classed as serotype A:1 (57.14%), 4 as serotype A:3 (19.05%) and 5 could not be typed (23.8%). Capsular typing, using multiplex polymerase chain reaction (PCR), demonstrated that 18 strains were capsular type A (85.7%), and 3 were type D (14.3%). The present findings suggest that a multiplex capsular PCR could be valuable for the rapid identification of P. multocida in cases of fowl cholera infection. A total of 5 isolates of P. multocida were selected to study their pathogenicity in embryonated chicken eggs instead of conducting a study in mature chickens. The results showed a variation in pathogenicity between the strains tested, namely: serotype A:1 strains caused 80% mortality, in contrast to 20% mortality by type D strains. Pathological findings included severe congestion of the entire embryo, haemorrhaging of the skin, feather follicles and toe, and ecchymotic haemorrhages on the liver of the inoculated embryos. The observations in this study indicate that P. multocida serogroup A could be highly pathogenic for mature chickens and therefore might be a cause of considerable economic losses in commercial production. A total of 10 isolates were subjected to antimicrobial susceptibility to determine the minimal inhibitory concentration of 7 antimicrobials. All isolates were susceptible to ciprofloxacin, florfenicol, streptomycin and sulphamethoxazol with trimethoprim and with varying degrees of sensitivity to the other agents

Effect of adenovirus infection on transgene expression under the adenoviral MLP/TPL and the CMVie promoter/enhancer in CHO cells

The adenovirus major late promoter (MLP) and its translational regulator – the tripartite leader (TPL) sequence – can actively drive efficient gene expression during adenoviral infection. However, both elements have not been widely tested in transgene expression outside of the adenovirus genome context. In this study, we tested whether the combination of MLP and TPL would enhance transgene expression beyond that of the most widely used promoter in transgene expression in mammalian cells, the cytomegalovirus immediate early (CMVie) promoter/enhancer. The activity of these two regulatory elements was compared in Chinese hamster ovary (CHO) cells. Although transient expression was significantly higher under the control of the CMVie promoter/enhance compared to the MLP/TPL, this difference was greater at the level of transcription (30 folds) than translation (11 folds). Even with adenovirus infection to provide additional elements (in trans), CMVie promoter/enhancer exhibited significantly higher activity relative to MLP/TPL. Interestingly, the CMVie promoter/enhancer was 1.9 folds more active in adenovirus-infected cells than in non-infected cells. Our study shows that the MLP-TPL drives lower transgene expression than the CMVie promoter/enhancer particularly at the transcription level. The data also highlight the utility of the TPL sequence at the translation level and/or possible overwhelming of the cellular translational machinery by the high transcription activity of the CMVie promoter/enhancer. In addition, here we present data that show stimulation of the CMVie promoter/enhancer by adenovirus infection, which may prove interesting in future work to test the combination of CMVie/TPL sequence, and additional adenovirus elements, for transgene expression

Detection and identification of Salmonella species in minced beef and chicken meats by using Multiplex PCR in Assiut city

The present study was undertaken to determine the incidence and distribution of Salmonella species in selected meat and chicken products purchased from retail supermarkets in Assiut, Egypt. A total of 75 samples including 25 samples each of minced frozen beef, frozen chicken legs and frozen chicken fillets were collected over a 7-month period between January and July 2009 and examined for the presence of Salmonella species. In addition, 28 children stool cultures were collected from hospitalized children resident in Pediatric University Hospital with diarrhea or fever. Out of the total 75 meat samples examined, Salmonella was detected in 5 (20%) of minced frozen beef, 9 (36%) of frozen chicken leg and 13 (52%) of frozen chicken fillet samples analyzed. Regarding the examined 28 children stool cultures, 3 (10.71 %) were found Salmonella positive. Of the total 30 Salmonella positive samples from all examined samples, five selected Salmonella isolates were further identified using multiplex PCR (m-PCR). Two serovars were the dominant serovar identified was Salmonella entrica subsp. entrica serovar Enteritidis (2 chicken leg isolates and 2 chicken breast fillets) followed by Salmonella entrica subsp. entrica serovar Kentucky (one minced beef isolate). The public health hazards of Salmonella were discussed and the suggestive measures to protect the consumers and improve the quality of meat and chicken products were given. [Veterinary World 2011; 4(1.000): 5-11