BACKGROUND: The mechanism of pathogenesis and the role of virulence factors of avian pathogenic E. coli is still ill-defined. The ostrich industry is expanding, resulting in the interaction between poultry and ostrich. It is reported that the investigation of iss and bor virulence genes together, due to their structural and functional similarities, is valuable. Objectives: The investigation and comparison of presence of two genes involved in serum resistance, iss and bor, in E. coli isolated from apparently healthy ostriches and poultry with colibacillosis. Methods: As a cross-sectional study, E. coli was recovered from fecal samples of apparently healthy ostriches and poultry with colibacillosis, and iss and bor genes were screened and compared via PCR in E. coli isolates. Results: iss frequencies, with no statistical difference, were 50% and 64.4% in E. coli isolated from apparently healthy ostriches and poultry with colibacillosis, respectively (P>0.05). 31.8% and 15.6% of E. coli isolated from apparently healthy ostriches and poultry with colibacillosis were positive for bor, respectively, with no statistical difference (P>0.05). 11.1% of isolates from colibacillosis and 18.2% of isolates from apparently healthy ostriches feces, with no statistical difference, were positive for both genes (P>0.05). Conclusions: Equal statistical distribution of both genes, bor and iss, between apparently healthy ostriches and poultry with colibacillosis and the health level of studied ostriches indicated that E. coli isolated from ostrich, probably employs other virulence factors instead of bor and iss to establish a disease. This hypothesis needs to examine more virulence genes in ostrich-origin E. coli. In addition, the ostrich feces could be introduced as a source of iss and bor genes.

BACKGROUND: Extensive effort is focused on identifying genomic conserved antigens in development of effective vaccine against Enterotoxigenic Escherichia coli. Antigen 43 is one of the members of a large secreted protein family named autotransporters in the E.coli and other gram negative bacteria. Autotransporter proteins have a similar conserved structure. Some of them are recognized during both experimental and naturally occurring ETEC infections. Antigen 43 is represented as a potential target in vaccine development because of its virulence functions such as cell aggregation, biofilm formation and its presence in convalescent sera from human patients with ETEC diarrhea. OBJECTIVES: In this study, we carefully investigate antigenic structure and immunogenicity of the Antigen 43 protein of strain 510 E.coli isolated from calves by experimental methods and immunoinformatics tools. METHODS: Amino acid sequence, physico-chemical parameters, stability, secondary and tertiary protein structure, the ability of induction the B and T cell immune responses by having the effective epitopes and also the allergenicity assessment were analyzed. RESULTS: In this study, we identified 15 peptide sequences that can potentially induce B and T cell immune responses and finally, 9 of them were introduced as antigens. CONCLUSIONS: The results of in-silico analysis on this protein suggested that it can be used in bovine colibacillosis vaccine development.

Two experiments were carried out to evaluate the efficacy of the administration of active dry yeast and/or lactobacillus preparation (AVI-BAC), either before or after the infection with antibiotic resistant field strain of Escherichia coli O127 (E. coli O127) in controlling the severity of infection in quail chicks. The quail chicks of the different experimental groups were infected orally for two successive days with 3x107 CFU of E. coli O-127 as an individual dose. The used field strain proved to be highly pathogenic for quails. Probiotics were supplemented in the drinking water for the different treatment groups at a dose level of 0.5 gm/L. The results revealed that the inclusion of lactobacilli or active dry yeast before E. coli infection has been highly effective in reducing mortality rate, organ invasion and the number of E. coli positive quail chicks. In addition, it decreased the severity of macroscopic and microscopic lesions in different organs in the probiotic treated groups as comparedto the infected controls. Lactobacilli preparations were more efficient in controlling the severity of the infection. On the other hand, the administration of yeast and /or lactobacilli after inducing E. coli infection reduced the mortality rate and the severity of lesion score in different organs but probiotics failed to protect quail chicks against the infection. It has been proved that the two probiotics have synergistic effect in controlling collibacillosis in quails.

Introduction: Colibacillosis – the most common disease of poultry, is caused mainly by avian pathogenic Escherichia coli (APEC). However, thus far, no pattern to the molecular basis of the pathogenicity of these bacteria has been established beyond dispute. In this study, genomes of APEC were investigated to ascribe importance and explore the distribution of 16 genes recognised as their virulence factors. Material and Methods: A total of 14 pathogenic for poultry E. coli strains were isolated, and their DNA was sequenced, assembled de novo, and annotated. Amino acid sequences from these bacteria and an additional 16 freely available APEC amino acid sequences were analysed with the DIFFIND tool to define their virulence factors. Results: The DIFFIND tool enabled quick, reliable, and convenient assessment of the differences between compared amino acid sequences from bacterial genomes. The presence of 16 protein sequences indicated as pathogenicity factors in poultry resulted in the generation of a heatmap which categorises genomes in terms of the existence and similarity of the analysed protein sequences. Conclusion: The proposed method of detection of virulence factors using the capabilities of the DIFFIND tool may be useful in the analysis of similarities of E. coli and other sequences deriving from bacteria. Phylogenetic analysis resulted in reliable segregation of 30 APEC strains into five main clusters containing various virulence associated genes (VAGs).

Avian colibacillosis is one of the most devastating diseases in chickens, resulting in high economic losses as well as high morbidity and mortality. Colistin is considered one of the most effective antimicrobials against colibacillosis. The recent discovery of mobile colistin resistance (mcr-1) determinants in humans and animals raised serious concerns about its potential dissemination among bacteria. This study aimed to investigate the presence of mcr1 gene among E. coli isolates in broiler chickens infected with colibacillosis. As an experimental design was performed on broiler chickens after molecular detection of mcr-1 gene to explore the efficacy of neomycin as a hydrophobic antibiotic wither in the mcr-1 absence or its existence after oral inoculation of E. coli strains. . Results revealed the high prevalence of colibacillosis among broiler farms in addition to highly spread of colistin resistance among E. coli isolates either through isolation on specific colistin resistance medium or molecular detection of the mcr-1 gene. On other hand, by histological examination we observed that the presence of the mcr-1 gene among E. coli isolates improved the treatment efficacy of the hydrophobic antibiotic. As a result of the significant antibiotic resistance issues and high risk of transmission of antibiotic-resistant bacteria and genes to humans, the development of antibacterials only for animal uses without cross-resistance to existing antibiotics might afford a solution in the future. Although there is an increase in acquired antibiotic resistance genes, it is possible to take advantage of this phenomenon, which in turn led to an increase in the sensitivity of some other antibiotics. Therefore, we recommend studying pharmacokinetic of antibacterials and making the most of this widespread phenomenon.

A total of 23,322 specimens collected between 2014 and 2017, froma total of 2,592 cases, were received in Veterinary Research Institute, Ipoh (VRI) from various states in Malaysia and testedfor common bacterial, viral, and parasitic diseases in pigs. The highest occurrence of isolated bacteria from 771 samples whichtested positive were Salmonella (47.38%) and Escherichia coli (15.68%), followed by Staphylococcus (6.62%), Streptococcus (5.57%), Klebsiella pneumonia (4.88%), Pseudomona (3.38%), Acinetobacter (3.14%), Aeromonas (2.79%), Enterobacter (2.44%), one each of Bacillus and Pasteurella multocida (1.74%), Enterococcus (1.39%) and Corynebacterium (1.05%). 1.74% of each bacteria detected were Moxarella, Aspergillus, Burkholderia andChromobacterium. Positive samples tested by ELISA was Japanese encephalitis virus (JEV) (9.15%), Aujezsky disease virus (ADV)(5.37%), porcine cirvo-virus-2 (PCV2) (5.09%) and porcine reproductive and respiratory syndrome virus (PRRSV) (4.52%). Positive amples tested by the molecular test wasPCV2 (1.62%), PRRSV (1.32%) and classical swine fever virus (CSFV) (0.4%). Serology tests were conducted on 11,305 samplesand reported positive for Brucella suis (15.32%), Brucella abortus (0.62%), Brucella melitensis (0.85%), and melioidosis (0.05%). Parasitology analyses on 99 samples. revealed presence of 10.1% coccidia and 1% each of helminths and Sarcocystis. Within the 4-year period, there were no positive samples for porcine parvovirus (PPV), Nipah virus, swine influenza virus (SIV), and bacteria of Johne’s disease and leptospirosis. Continuous assessment is required to establish a comprehensive baseline data of swine diseases in Malaysia.

Colibacillosis is a disease caused by avian pathogenic E. coli (APEC) and is one of the principle cause of morbidity and mortality in poultry worldwide which is represented by a complex syndrome characterized by multiple organ lesions. This study was carried out to determine phylogenetic grouping and virulenceassociated genes contained by E. coli isolates which is related in causing disease in chicken. E. coli isolates obtained from clinical cases of Veterinary ResearchInstitute were re-identified by conventional methods. Phylogenetic grouping of the isolates was determined by triplex polymerase chain reaction (PCR), and the presence of eight virulence genes were identified by multiplex PCR. A total of 125 E. coli isolates were subjected toanalysis of phylogenetic background and virulence associated genes profiling. Phylogenetic analysis demonstrated that most of the E. coli isolated from chicken in this study belonged to group B1 (36.0%),group D (28.0%), group A (27.2%) and group B2 (8.8%). Multiplex PCR analysis demonstrated that 96 (78.6%) of the E. coli isolates harbored at least one virulencegene, while 29 (23.3%) did not contain any virulence genes tested. The most prevalent virulence genes identified were iss (51.2%), followed by iucD (36.0%),tsh (32.8%), vat (16.0%), astA (13.6%), irp2 (11.2%), papC (9.6%) and the least is cva/cvi gene (0%). None of the isolates harbored more than four virulence genes.Each of phylogenetic groups presented with different combinations of virulence genes, with no specific combinations of virulence genes found to correlate withE. coli phylogroups. None of the E. coli isolates harbored more than four virulence genes, suggesting that E. coli isolates from chicken in this study appear to bederived from commensal strains and may relate to environmental predispose factors especially stress factors in the host to establish infection.

Fascioliasis is an importantparasitic disease caused by the liver flukeFasciola gigantica in Malaysia. Theinfestation of liver fluke in ruminants;cattle, sheep, goats and buffaloes can resultin economic losses to the country mainlydue to the drop in livestock production,reduction in growth rate, condemnationof liver, reduction in draught power andhigh usage of anthelmintics. This paperdescribes a case of liver fluke infestationin a two year old male buffalo that waseventually slaughtered. The buffalowas reported to be emaciated and wasreared in an oil palm plantation for useas draught power in buffalo-drawn cartsloaded with oil palm bunches; alongwith 18 other buffaloes of various ages.Previously, there were two cases of buffalodeaths from the same herd. The organand faecal samples were sent to KuantanRegional Veterinary Laboratory (RVL)for diagnostic work up. The receivedsamples were then sent to parasitology,histopathology and bacteriology sectionsfor laboratory analysis and confirmationon the pathogens. The bacteriology resultshowed Escherichia coli isolated in allinternal organs. Presence of adult flukes(Fasciola gigantica) were observed inthe bile duct of the liver through grossexamination and also histopathologicalevaluation and supported by the positiveresult of Fasciola ova via sedimentationtest conducted from the faecal sample, thusjustifying the final diagnosis as severe liverfluke infestation leading to emaciation andsimultaneously having colibacillosis.

Escherichia coli (E.coli) infections pose significant health risks to poultry and humans globally. In the face of antibiotic-resistant strains, metal oxide nanoparticles and plant extracts have emerged as promising alternatives. This study evaluated the effectiveness of copper oxide nanoparticles (CuO-NPs) and black elderberry extract (BEE) against E. coli O78 infection in specific pathogen-free chicks. The birds were divided into four groups: a negative control NC, a positive control (PC; challenged with E. coli O78), CuO-NPs treatment post-challenge, and BEE treatment post-challenge. Various parameters, including clinical signs, organ lesions, bacterial load, biochemical markers, and histopathology, were assessed. Both CuO-NPs and BEE demonstrated a reduction in clinical morbidity, organ damage, and E. coli counts compared to the PC. However, BEE exhibited slightly greater efficacy in alleviating liver and kidney dysfunction. Overall, CuO-NPs and BEE hold therapeutic potential against avian colibacillosis, likely acting through antimicrobial and immunomodulatory mechanisms. These findings underscore the potential of bio-based nanoparticles and plant extracts as safer, multi-modal alternatives to antibiotics for avian colibacillosis. Further optimization and mechanistic studies are needed to support their clinical application.

Colibacillosis is animportant disease affecting the poultryindustry in many countries, caused bythe Avian Pathogenic E. coli (APEC):it manifests as various clinical signs. Itcontributes significantly to economicloss for poultry farmers as a result ofhigh mortality and morbidity in poultry.To overcome this, antibiotics have beenwidely used to eliminate E. coli infectionin poultry farms in recent years. Treatmentwith antibiotics has been considered as avital regimen to control E. coli infectionat the farm level for many years. However,high frequency of antibiotic resistance ofE. coli isolates from chicken has becomethe centre of attention due to public healthimportance. The aim of the present study isto determine the multidrug resistant profilesof E. coli strains isolated from chicken.E. coli isolates obtained from clinicalcases were re-identified and classified byconventional methods. Multidrug resistantprofiles against 13 different antibiotics of125 E. coli isolates were determined byusing disk diffusion method accordingto Clinical Laboratory Standard Institute(CLSI). Antibiogram revealed that 81.6%of the E. coli isolates showed multidrugresistant profiles to different antibiotics.Most of the E.coli isolates were highlyresistant to erythromycin (52.8%), followedwith tetracycline (52.0%), spectinomycin(39.2%), trimethoprim (38.4%) andflumequin (37.6%). Out of 125 isolatestested, 19.2% were resistant to more thaneight antibiotics, with one isolates found tobe multidrug resistant to most of antibioticsexcept polymyxin B. These findings alsodemonstrated that most of the isolateswere susceptible to antibiotics commonlyused for E.coli infections treatment inpoultry with lowest resistant score againstpolymyxin B (92.8%) and colistin (92.0%).Moderate resistant profiles were observedtowards amoxycilin (25.6%), apramycin(16%), kanamycin (8.8%) and streptomycin(8.0%). High percentage of multidrugresistance was found among the E. coliisolated from chicken as an indicator tomore serious problems in animal health.Therefore, continuous surveillance of antibiotic resistance profiles in chicken andother food animals is crucial to ensure foodchain safety