Rasha Mohamed - Academia.edu (original) (raw)

Papers by Rasha Mohamed

Journal of Applied Sciences, 2019

Mansoura Veterinary Medical Journal, 2013

Biocontrol Science, 2021

Aeromonas species are facultatively anaerobic, Gram-negative, motile, short, rod-shaped bacilli, ... more Aeromonas species are facultatively anaerobic, Gram-negative, motile, short, rod-shaped bacilli, and non-spore-forming bacterium with widely host affection as fish, domestic chicken, most vertebrates, and humans (Rey et al., 2009). Aeromonas species were related to diseases in freshwater and marine fish species including Motile Aeromonas Septicemia and Epizootic Ulcerative Syndrome in addition to deleterious signs accompanied with affected tilapia as skin darkness, scales detachment, red sores, exophthalmia, and fin erosions (Viji et al., 2011; Dias et al., 2016). The postmortem examination showed hemorrhages with enlargement of internal organs (El Deen et al., 2014). Most human affections arise to immunocompramised patients with multiple gastrointestinal tract infections, meningitis, endocarditis, peritonitis, hemolytic uremic syndrome, septicemia, and food poisoning (Guerra et al., 2007). A. hydrophila, one of the most vigorous Aeromonas species, able to induce incurable problems to freshwater fish aquaculture in Egypt

Journal of Veterinary Medical Science

This study was organized to investigate the prevalence, antibiotic and disinfectant resistance ph... more This study was organized to investigate the prevalence, antibiotic and disinfectant resistance phenotypes and genotypes as well as plasmid profiles of Shigella species isolated from raw cow milk and milk products in Egypt. Genotypic analysis was performed to determine the presence of β-lactamase encoding genes (bla TEM , bla CTX-M , bla OXA-1 and bla SHV), tet(A) and qacE∆. Forty-two (7%) Shigella isolates (S. dysenteriae, S. flexneri, and S. sonnei) were recovered, with S. dysenteriae as the predominant type. Antibiotic sensitivity tests showed that 71.4% of Shigella isolates were resistant to three or more antibiotic classes (multidrug-resistant). High resistance rates were observed against tetracyclines (100%), ampicillin, amoxicillin-clavulanate (90.5%, each) and cefaclor (66.7%), while no resistance was detected against imipenem, sulfamethoxazole/ trimethoprim, and azithromycin. Disinfectant susceptibility test of Shigella isolates revealed resistance to phenolic compound (vanillic acid), while 85.7% of the Shigella isolates were resistant to benzalkonium chloride. Uniplex PCR analysis declared the existence of β-lactamase encoding genes (bla TEM in all isolates and bla CTX-M in 28.6% of isolates) and, tet(A) in all isolates and 85.7% of the isolates were positive for qacE∆1, while all isolates were negative for bla OXA-1 and bla SHV. All Shigella extended spectrum β-lactamases (ESBL) producers (12, 100%) were positive for the bla TEM , bla CTX-M , and qacE∆1 genes. Furthermore, plasmid profiling revealed seven distinct plasmid patterns (P1-P7), ranging from 1.26 to 33.61 kb, among all the Shigella strains; S. dysenteriae exhibited the greatest variance. The co-transfer of β-lactamase genes (bla TEM and bla CTX-M) and qacE∆1 genes was observed by conjugation from all ESBL producers to a recipient strain. These findings indicate the emergence of Shigella species in Egypt that exhibited multi-resistance to either antibiotics (particularly ESBL producer strains) or disinfectants. Thus, the resistance of Shigella species should regularly be monitored and appropriate measures should be taken to manage this problem.

Brazilian Journal of Biology, 2024

Pseudomonas fluorescens is one of the main causes of septicemic diseases among freshwater fish, c... more Pseudomonas fluorescens is one of the main causes of septicemic diseases among freshwater fish, causing severe economic losses and decreasing farm efficiency. Thus, this research was aimed to investigate the occurrence of P. fluorescens in Nile Tilapia (O. niloticus) fish in Egypt, gene sequencing of 16SrDNA gene, and antimicrobial susceptibility. P. fluorescens strains were detected in 32% (128\400) of apparently healthy (9%; 36\400) and diseased (23%; 92\400) Nile tilapia fish. The highest prevalence was observed in gills of fish, 31.3% followed by intestine 26.9%, liver 24.2%, and kidneys 17.6%. The PCR results for the 16SrDNA gene of P. fluorescens showed 16SrDNA gene in 30% of examined isolates. Moreover, Homogeny and a strong relationship between strains of P. fluorescens was confirmed using 16SrDNA sequences. Beside the responsibility of 16SrDNA gene on the virulence of P. fluorescens. The results of antimicrobial susceptibility tests revealed that all strains were resistant ...

Mansoura Veterinary Medical Journal, 2020

A study was carried out to investigate the prevalence of mastitis caused by Streptococcus agalact... more A study was carried out to investigate the prevalence of mastitis caused by Streptococcus agalactiae and Streptococcus dysgalactiae in cows and buffalo reared in households and smallholder dairy farms, and to detect their antibiotics susceptibility, and molecular investigation of some virulence genes (cylE and mig genes). Design: Observational study. Samples: A total of 288 milk samples were gathered from 72 mastitic animals (48 cows and 24 buffalo) from households and smallholder dairy farms in Dakahlia and Domiatte Governorates, Egypt. Procedures: Isolation and identification of S. agalactiae and S. dysgalactiae was performed using conventional techniques. The identified isolates were examined for antimicrobial resistance by disk diffusion assay, Minimum inhibitory concentration MIC by broth microdilution method as well as virulence genes (cylE and mig genes) by polymerase chain reaction (PCR). Results: Forty-five (62.5%) out of 72 animals showed the clinical signs of mastitis. Microbiological evaluation of 288 mastitis milk samples was displayed 190 (65.72%) streptococci strains composing of 114 (60%) S. agalactiae and 76 (40%) S. dysgalactiae strains. The antibiotic susceptibility tests revealed that S. agalactiae strains was resistant to trimethoprim (100%), followed by tetracycline and minocycline (37.7%), whereas intermediate resistant was observed to other tested antibiotics. Moreover, S. dysgalactiae strains were highly resistant to lincomycin, tetracycline (87.52 each), followed by trimethoprim (81.6) and minocycline (75%), while all strainswere susceptible to penicillin, amoxicillin, cephapirin, and cefquinome. Additionally, the highest MIC with the widest range (1 to ≥128 μg/mL) was observed to trimethoprim for S. agalactiae and to erythromycin and lincomycin for S. dysgalactiae. In contrast, the lowest MIC was detected to penicillin, amoxicillin, cefquinome, and erythromycin for S. agalactiae and to penicillin, amoxicillin, cephapirin, cefquinome, and rifaximin for S. dysgalactiae. The cylE gene was displayed in 6 (60%) S. agalactiae strains, whereas the mig gene was found in 4 (40%) S. dysgalactiae strains. Conclusion and clinical relevance: Our data highlights the importance of awareness of antibiotic resistant strains of S. agalactiae and S. dysgalactiae in various mastitic animals (cows and buffalo) in Egypt.

Mycotoxins are toxic complexes generated by various genera of filamentous fungi and pose severe p... more Mycotoxins are toxic complexes generated by various genera of filamentous fungi and pose severe public health hazards due to their carcinogenic and mutagenic properties. Toxigenic fungi produce mycotoxins on various foodstuffs when favorable conditions for their production are exist. The most important mycotoxin-producing fungal genera are Aspergillus, Fusarium and Penicillium. The major mycotoxin of concern, including aflatoxins, trichothecenes, ochratoxins, patulin, fumonisins, and zearalenone, are expressively contaminate foodstuffs, with implications for human and animal health. There are various environmental factors influencing mycotoxin production involving temperature, water activity, animal type, aeration, pH, light, and nature of substrate. The temperature and relative moistness range for ideal mycotoxin generation may shift from that steady fungal development. The high temperature and moistness stress primarily have a potential issue. A full understanding of the existence...

Veterinary World, 2021

Background and Aim: Escherichia coli is the cause of avian colibacillosis, a significant threat t... more Background and Aim: Escherichia coli is the cause of avian colibacillosis, a significant threat to the poultry industry and public health. Thus, this study investigated the prevalence of E. coli in diseased chicken broilers, pathological effects of these bacteria, and interleukin (IL) gene expression of different serotypes of E. coli (O78, O26, O44, and O55) on experimentally infected chickens. Materials and Methods: A total of 295 organ samples (liver, lungs, heart, and spleen) from 59 diseased broiler chickens were used for conventional identification of E. coli. Chickens were orally infected with one of the following E. coli serotypes (O78, O26, O44, or O55) and examined for clinical signs, mortality, macroscopic and microscopic lesions, and IL gene expression using real-time quantitative polymerase chain reaction. Results: E. coli was isolated from 53.2% of broiler chicken organs with a high prevalence in lungs (26.1%). The most prevalent serotypes were O78, O26, O44, O55, O157,...

Mansoura Veterinary Medical Journal, 2020

To investigate prevalence of Aeromonas. hydrophila and Staphylococcus aureus in seafood, and to d... more To investigate prevalence of Aeromonas. hydrophila and Staphylococcus aureus in seafood, and to detect the consistent virulence genes as well as to assess the antimicrobial susceptibility. Design: Observational study. Samples: 280 marketed seafood samples (178 shrimp, 54 oysters, 26 crabs, 18 squid, and 4 octopuses). Procedures: Isolation and identification of Aeromonas hydrophila and Staphylococcus aureus were performed using conventional methods. The identified isolates were examined for virulence genes (aer and hly genes for A. hydrophila as well as nuc and sea genes for S. aureus) as well as for antimicrobial susceptibility. Results: A. hydrophila was isolated from 40 of the 280 seafood samples (14.3%), with the highest prevalence (22.2%) in oyster samples, whereas S. aureus occurred in 50 samples (17.9%) with the highest prevalence (20.2%) in shrimp samples. Moreover, aer and hly genes were detected in all isolates of A. hydrophila, and thermonuclease (nuc) gene was detected in all tested S. aureus strains, whereas staphylococcal enterotoxin A (sea) gene was found in only 44% of S. aureus strains. A. hydrophila strains were absolutely resistant to amoxicillin (100%), followed by ceftriaxone (80%), chloramphenicol (77.5%), trimethoprim-sulfamethoxazole (65%), and tetracycline (55%), whereas S. aureus strains showed high resistance to penicillin (86%), followed by amoxicillin-clavulanic acid (72%), and trimethoprimsulfamethoxazole (58%). Multidrug resistance (MDR) to more than two classes of antibiotics was found in 77.5% (31/40) of A. hydrophila strains and 66% (28/50) of S. aureus isolates. Conclusion and clinical relevance: Our data highlights the importance of awareness of virulent strains of MDR A. hydrophila and S. aureus strains of seafood samples in Egypt. Consequently, the continuous surveillance of these bacteria in seafood with a strong focus on their antibiotic resistance characteristics should be considered in further studies.

Indian Journal of Poultry Science, 2017

Younis, Gamal A., Elkenany, Rasha M., Radwan, Mona M. and Allah, Magda M. Abd. 2017. Antimicrobia... more Younis, Gamal A., Elkenany, Rasha M., Radwan, Mona M. and Allah, Magda M. Abd. 2017. Antimicrobial resistant profiles of Methicillin-resistant Staphylococcus aureus (MRSA) recovered from broiler chicken populations in Egypt. Indian Journal of Poultry Science, 52(3): 332-337. Little is still known about prevalence of methicillin resistant Staphylococcus aureus (MRSA) in broilers, so this study aimed to determine its prevalence, antibiogram patterns and the site of resistant genes using PCR. About 57 staphylococcal isolates of 78 samples (73%) recovered from broiler chicken were classified into coagulase positive staphylococci (CPS) (40.3%) and coagulase negative staphylococci (CNS) (59.6%). The CPS isolates were identified as MRSA (34.8%) and methicillin sensitive Staphylococcus aureus (MSSA) (65.2%) according to oxacillin resistance by disc diffusion method. The CPS isolates showed the highest rate of resistance to trimethoprim/sulphamethoxazole (100% and 93.3% for MRSA and MSSA respectively), erythromycin (100% and 93.3% for MRSA and MSSA respectively), oxacillin and cefoxitin (100%, 87.5% MRSA and 0%, 6.7% MSSA respectively), ceftriaxone (87.5% and 73.3% for MRSA and MSSA respectively) and amoxicillin (75% and 40% for MRSA and MSSA respectively). Moreover, the CNS showed resistance against trimethoprim/sulphamethoxazole with 85.3%, followed by 79.4% erythromycin, 55.9% ceftriaxone, 47% cefoxitin, 47% amoxicillin, and oxacillin (44%). PCR assay revealed that four (80%) of five MRSA isolates were harbored mecA gene. The screening of mecA, dfrA and ermC resistant genes was done on plasmid and chromosomal DNA of four MRSA isolates. All of them were chromosome linked genes, but none of these resistant genes were detected on plasmid DNA. All examined isolates (100%) contained ermC gene. In addition, the dfrA gene was detected in 2 (50%) out of the 4 isolates.

Brazilian Journal of Biology

The current study describes the presence of Bacillus cereus (B. cereus) in contaminated foods of ... more The current study describes the presence of Bacillus cereus (B. cereus) in contaminated foods of animal source and ready for human consumption with highlighting on their virulence contributing factors by detection of its virulence genes in addition to identification of their sequencing. Three hundred sixty food samples categorized as (228) meat products and (132) milk products were examined for B. cereus isolation and all of these isolates were confirmed by biochemical tests. Eighteen strains obtained from different food samples were examined for the attendance of a number of virulence genes (nheA, cytK, entFM, bceT and hblC genes) using uniplex PCR method. Furthermore, the B. cereus strains were valued for the sequencing of described genes. Generally 24.44% (88/360) food samples classified as 11.11% (40/360) meat products and 13.33% (48/360) milk products carried B. cereus according to cultural and biochemical properties, with geometric mean (1.5×107±0.15 CFU/g or mL) . The highest...

Environmental Science and Pollution Research, 2022

Listeria monocytogenes (L. monocytogenes) is frequently detected in ruminants, especially dairy c... more Listeria monocytogenes (L. monocytogenes) is frequently detected in ruminants, especially dairy cattle, and associated with the sporadic and epidemic outbreak of listeriosis in farms. In this epidemiological study, the prevalence, virulence, antibiotic resistance profiles, and genetic diversity of L. monocytogenes in three Egyptian dairy cattle farms were investigated. The risk factors associated with the fecal shedding of L. monocytogenes were analyzed. The L. monocytogenes strains from the three farms were categorized into distinct genotypes based on sampling site and sample type through enterobacterial repetitive intergenic consensus polymerase chain reaction (ERIC-PCR). A total of 1896 samples were collected from animals, environments, and milking equipment in the three farms. Results revealed that 137 (7.23%) of these samples were L. monocytogenes positive. The prevalence of L. monocytogenes in the animal samples was high (32.1%), and the main environmental source of prevalent ...

Pakistan Journal of Biological Sciences

Clostridium perfringens is one of the most widespread pathogen producing toxins related to variab... more Clostridium perfringens is one of the most widespread pathogen producing toxins related to variable pathogenic conditions, particularly food poisoning in humans. Thus, this study described the prevalence, enumeration, toxigenic types and antibiotic susceptibility of C. perfringens strains isolated from minced meat in Egypt as well as the validation of a real-time polymerase chain reaction (PCR) test for the identification of C. perfringens toxin genes. A high prevalence of C. perfringens (98/105, 93.3%) was detected in minced meat samples. The total count of viable C. perfringens in 23 samples was 2.0 × 102 to 4.5 × 102 with a mean value 3.7 × 102 ± 1.07 × 102 CFU/g. The toxin typing of C. perfringens based on lecithinase activity and dermonecrotic reactions in albino guinea pig exhibited 33 (33.7%) as toxigenic strains of C. perfringens type A and 65 (66.3%) as non-toxigenic strains. Antibiotic susceptibility testing of isolates against 15 different antimicrobial agents indicat...

Veterinary Research Communications

Advances in Animal and Veterinary Sciences, 2019

F resh water fish, Oreochromis niloticus (Nile tilapia) and Clarias gariepinus (African catfish),... more F resh water fish, Oreochromis niloticus (Nile tilapia) and Clarias gariepinus (African catfish), is one of the most important protein sources for people in a lot of countries (Iqbal et al., 2012). Aquacultures incorporated into the farming system have been revealed to develop food security with slight external inputs (Wetengere, 2010). However, mortality and sever economic losses amongst the ornamental and food fish farming industries as the chief features of fungal infections were exhibited (Ali, 2015). For example, epizootic ulcerative syndrome (EUS) infection was one of most common disease caused by Aspergillus niger and Aspergillus fumigatu in fresh water fish (Chauhan, 2013). Really, the incidence and diversity of fungi as well as their secondary metabolites in aquatic systems are occupied a worldwide growing interest. Nonetheless, such concern is hindered by the scarce data about aquatic fungi in the investigations (Magwaza et al., 2017). Many of the fungi affected fish are considered opportunists. Fish is attacked when it is immunocompromised or stressed owing to unfavorable environment or subsequent to bacterial in

Veterinary World, Oct 24, 2021

Background and Aim: Escherichia coli is the cause of avian colibacillosis, a significant threat t... more Background and Aim: Escherichia coli is the cause of avian colibacillosis, a significant threat to the poultry industry and public health. Thus, this study investigated the prevalence of E. coli in diseased chicken broilers, pathological effects of these bacteria, and interleukin (IL) gene expression of different serotypes of E. coli (O78, O26, O44, and O55) on experimentally infected chickens.

Materials and Methods: A total of 295 organ samples (liver, lungs, heart, and spleen) from 59 diseased broiler chickens were used for conventional identification of E. coli. Chickens were orally infected with one of the following E. coli serotypes (O78, O26, O44, or O55) and examined for clinical signs, mortality, macroscopic and microscopic lesions, and IL gene expression using real-time quantitative polymerase chain reaction.

Results: E. coli was isolated from 53.2% of broiler chicken organs with a high prevalence in lungs (26.1%). The most prevalent serotypes were O78, O26, O44, O55, O157, and O127 prevalence of 27.8, 22.2, 16.7, 16.7, 5.6, and 5.6%, respectively. In the experimental design, five groups (G1-G5) of birds were established. G1 served as the negative control group, while G2-G5 were challenged orally with E. coli O78, O26, O55, or O44, respectively. Chickens infected with E. coli O78 or O26 showed significant clinical signs in comparison to the other infected birds. Mortality (13.3%) was only observed in birds infected with E. coli O78. Necropsy of dead birds after E. coli O78 infection showed pericarditis, enteritis, airsacculitis, and liver and lung congestion. More severe histopathological changes were observed in intestines, spleen, liver, and lung from chickens infected with either E. coli O78 or O26 than for birds infected with other serotypes. On the 2nd day post-infection, E. coli challenge, particularly with E. coli O78, displayed significantly upregulated levels of ileal IL-6 and IL-8, but ileal IL-10 level tended to be downregulated in comparison to the control group.

Conclusion: This study assessed the application of cytokines as therapeutic agents against infectious diseases, particularly colibacillosis.

Environmental Science and Pollution Research

Pakistan Journal of Biological Sciences

Journal of Applied Sciences, 2019

Mansoura Veterinary Medical Journal, 2013

Biocontrol Science, 2021

Aeromonas species are facultatively anaerobic, Gram-negative, motile, short, rod-shaped bacilli, ... more Aeromonas species are facultatively anaerobic, Gram-negative, motile, short, rod-shaped bacilli, and non-spore-forming bacterium with widely host affection as fish, domestic chicken, most vertebrates, and humans (Rey et al., 2009). Aeromonas species were related to diseases in freshwater and marine fish species including Motile Aeromonas Septicemia and Epizootic Ulcerative Syndrome in addition to deleterious signs accompanied with affected tilapia as skin darkness, scales detachment, red sores, exophthalmia, and fin erosions (Viji et al., 2011; Dias et al., 2016). The postmortem examination showed hemorrhages with enlargement of internal organs (El Deen et al., 2014). Most human affections arise to immunocompramised patients with multiple gastrointestinal tract infections, meningitis, endocarditis, peritonitis, hemolytic uremic syndrome, septicemia, and food poisoning (Guerra et al., 2007). A. hydrophila, one of the most vigorous Aeromonas species, able to induce incurable problems to freshwater fish aquaculture in Egypt

Journal of Veterinary Medical Science

This study was organized to investigate the prevalence, antibiotic and disinfectant resistance ph... more This study was organized to investigate the prevalence, antibiotic and disinfectant resistance phenotypes and genotypes as well as plasmid profiles of Shigella species isolated from raw cow milk and milk products in Egypt. Genotypic analysis was performed to determine the presence of β-lactamase encoding genes (bla TEM , bla CTX-M , bla OXA-1 and bla SHV), tet(A) and qacE∆. Forty-two (7%) Shigella isolates (S. dysenteriae, S. flexneri, and S. sonnei) were recovered, with S. dysenteriae as the predominant type. Antibiotic sensitivity tests showed that 71.4% of Shigella isolates were resistant to three or more antibiotic classes (multidrug-resistant). High resistance rates were observed against tetracyclines (100%), ampicillin, amoxicillin-clavulanate (90.5%, each) and cefaclor (66.7%), while no resistance was detected against imipenem, sulfamethoxazole/ trimethoprim, and azithromycin. Disinfectant susceptibility test of Shigella isolates revealed resistance to phenolic compound (vanillic acid), while 85.7% of the Shigella isolates were resistant to benzalkonium chloride. Uniplex PCR analysis declared the existence of β-lactamase encoding genes (bla TEM in all isolates and bla CTX-M in 28.6% of isolates) and, tet(A) in all isolates and 85.7% of the isolates were positive for qacE∆1, while all isolates were negative for bla OXA-1 and bla SHV. All Shigella extended spectrum β-lactamases (ESBL) producers (12, 100%) were positive for the bla TEM , bla CTX-M , and qacE∆1 genes. Furthermore, plasmid profiling revealed seven distinct plasmid patterns (P1-P7), ranging from 1.26 to 33.61 kb, among all the Shigella strains; S. dysenteriae exhibited the greatest variance. The co-transfer of β-lactamase genes (bla TEM and bla CTX-M) and qacE∆1 genes was observed by conjugation from all ESBL producers to a recipient strain. These findings indicate the emergence of Shigella species in Egypt that exhibited multi-resistance to either antibiotics (particularly ESBL producer strains) or disinfectants. Thus, the resistance of Shigella species should regularly be monitored and appropriate measures should be taken to manage this problem.

Brazilian Journal of Biology, 2024

Pseudomonas fluorescens is one of the main causes of septicemic diseases among freshwater fish, c... more Pseudomonas fluorescens is one of the main causes of septicemic diseases among freshwater fish, causing severe economic losses and decreasing farm efficiency. Thus, this research was aimed to investigate the occurrence of P. fluorescens in Nile Tilapia (O. niloticus) fish in Egypt, gene sequencing of 16SrDNA gene, and antimicrobial susceptibility. P. fluorescens strains were detected in 32% (128\400) of apparently healthy (9%; 36\400) and diseased (23%; 92\400) Nile tilapia fish. The highest prevalence was observed in gills of fish, 31.3% followed by intestine 26.9%, liver 24.2%, and kidneys 17.6%. The PCR results for the 16SrDNA gene of P. fluorescens showed 16SrDNA gene in 30% of examined isolates. Moreover, Homogeny and a strong relationship between strains of P. fluorescens was confirmed using 16SrDNA sequences. Beside the responsibility of 16SrDNA gene on the virulence of P. fluorescens. The results of antimicrobial susceptibility tests revealed that all strains were resistant ...

Mansoura Veterinary Medical Journal, 2020

A study was carried out to investigate the prevalence of mastitis caused by Streptococcus agalact... more A study was carried out to investigate the prevalence of mastitis caused by Streptococcus agalactiae and Streptococcus dysgalactiae in cows and buffalo reared in households and smallholder dairy farms, and to detect their antibiotics susceptibility, and molecular investigation of some virulence genes (cylE and mig genes). Design: Observational study. Samples: A total of 288 milk samples were gathered from 72 mastitic animals (48 cows and 24 buffalo) from households and smallholder dairy farms in Dakahlia and Domiatte Governorates, Egypt. Procedures: Isolation and identification of S. agalactiae and S. dysgalactiae was performed using conventional techniques. The identified isolates were examined for antimicrobial resistance by disk diffusion assay, Minimum inhibitory concentration MIC by broth microdilution method as well as virulence genes (cylE and mig genes) by polymerase chain reaction (PCR). Results: Forty-five (62.5%) out of 72 animals showed the clinical signs of mastitis. Microbiological evaluation of 288 mastitis milk samples was displayed 190 (65.72%) streptococci strains composing of 114 (60%) S. agalactiae and 76 (40%) S. dysgalactiae strains. The antibiotic susceptibility tests revealed that S. agalactiae strains was resistant to trimethoprim (100%), followed by tetracycline and minocycline (37.7%), whereas intermediate resistant was observed to other tested antibiotics. Moreover, S. dysgalactiae strains were highly resistant to lincomycin, tetracycline (87.52 each), followed by trimethoprim (81.6) and minocycline (75%), while all strainswere susceptible to penicillin, amoxicillin, cephapirin, and cefquinome. Additionally, the highest MIC with the widest range (1 to ≥128 μg/mL) was observed to trimethoprim for S. agalactiae and to erythromycin and lincomycin for S. dysgalactiae. In contrast, the lowest MIC was detected to penicillin, amoxicillin, cefquinome, and erythromycin for S. agalactiae and to penicillin, amoxicillin, cephapirin, cefquinome, and rifaximin for S. dysgalactiae. The cylE gene was displayed in 6 (60%) S. agalactiae strains, whereas the mig gene was found in 4 (40%) S. dysgalactiae strains. Conclusion and clinical relevance: Our data highlights the importance of awareness of antibiotic resistant strains of S. agalactiae and S. dysgalactiae in various mastitic animals (cows and buffalo) in Egypt.

Mycotoxins are toxic complexes generated by various genera of filamentous fungi and pose severe p... more Mycotoxins are toxic complexes generated by various genera of filamentous fungi and pose severe public health hazards due to their carcinogenic and mutagenic properties. Toxigenic fungi produce mycotoxins on various foodstuffs when favorable conditions for their production are exist. The most important mycotoxin-producing fungal genera are Aspergillus, Fusarium and Penicillium. The major mycotoxin of concern, including aflatoxins, trichothecenes, ochratoxins, patulin, fumonisins, and zearalenone, are expressively contaminate foodstuffs, with implications for human and animal health. There are various environmental factors influencing mycotoxin production involving temperature, water activity, animal type, aeration, pH, light, and nature of substrate. The temperature and relative moistness range for ideal mycotoxin generation may shift from that steady fungal development. The high temperature and moistness stress primarily have a potential issue. A full understanding of the existence...

Veterinary World, 2021

Background and Aim: Escherichia coli is the cause of avian colibacillosis, a significant threat t... more Background and Aim: Escherichia coli is the cause of avian colibacillosis, a significant threat to the poultry industry and public health. Thus, this study investigated the prevalence of E. coli in diseased chicken broilers, pathological effects of these bacteria, and interleukin (IL) gene expression of different serotypes of E. coli (O78, O26, O44, and O55) on experimentally infected chickens. Materials and Methods: A total of 295 organ samples (liver, lungs, heart, and spleen) from 59 diseased broiler chickens were used for conventional identification of E. coli. Chickens were orally infected with one of the following E. coli serotypes (O78, O26, O44, or O55) and examined for clinical signs, mortality, macroscopic and microscopic lesions, and IL gene expression using real-time quantitative polymerase chain reaction. Results: E. coli was isolated from 53.2% of broiler chicken organs with a high prevalence in lungs (26.1%). The most prevalent serotypes were O78, O26, O44, O55, O157,...

Mansoura Veterinary Medical Journal, 2020

To investigate prevalence of Aeromonas. hydrophila and Staphylococcus aureus in seafood, and to d... more To investigate prevalence of Aeromonas. hydrophila and Staphylococcus aureus in seafood, and to detect the consistent virulence genes as well as to assess the antimicrobial susceptibility. Design: Observational study. Samples: 280 marketed seafood samples (178 shrimp, 54 oysters, 26 crabs, 18 squid, and 4 octopuses). Procedures: Isolation and identification of Aeromonas hydrophila and Staphylococcus aureus were performed using conventional methods. The identified isolates were examined for virulence genes (aer and hly genes for A. hydrophila as well as nuc and sea genes for S. aureus) as well as for antimicrobial susceptibility. Results: A. hydrophila was isolated from 40 of the 280 seafood samples (14.3%), with the highest prevalence (22.2%) in oyster samples, whereas S. aureus occurred in 50 samples (17.9%) with the highest prevalence (20.2%) in shrimp samples. Moreover, aer and hly genes were detected in all isolates of A. hydrophila, and thermonuclease (nuc) gene was detected in all tested S. aureus strains, whereas staphylococcal enterotoxin A (sea) gene was found in only 44% of S. aureus strains. A. hydrophila strains were absolutely resistant to amoxicillin (100%), followed by ceftriaxone (80%), chloramphenicol (77.5%), trimethoprim-sulfamethoxazole (65%), and tetracycline (55%), whereas S. aureus strains showed high resistance to penicillin (86%), followed by amoxicillin-clavulanic acid (72%), and trimethoprimsulfamethoxazole (58%). Multidrug resistance (MDR) to more than two classes of antibiotics was found in 77.5% (31/40) of A. hydrophila strains and 66% (28/50) of S. aureus isolates. Conclusion and clinical relevance: Our data highlights the importance of awareness of virulent strains of MDR A. hydrophila and S. aureus strains of seafood samples in Egypt. Consequently, the continuous surveillance of these bacteria in seafood with a strong focus on their antibiotic resistance characteristics should be considered in further studies.

Indian Journal of Poultry Science, 2017

Younis, Gamal A., Elkenany, Rasha M., Radwan, Mona M. and Allah, Magda M. Abd. 2017. Antimicrobia... more Younis, Gamal A., Elkenany, Rasha M., Radwan, Mona M. and Allah, Magda M. Abd. 2017. Antimicrobial resistant profiles of Methicillin-resistant Staphylococcus aureus (MRSA) recovered from broiler chicken populations in Egypt. Indian Journal of Poultry Science, 52(3): 332-337. Little is still known about prevalence of methicillin resistant Staphylococcus aureus (MRSA) in broilers, so this study aimed to determine its prevalence, antibiogram patterns and the site of resistant genes using PCR. About 57 staphylococcal isolates of 78 samples (73%) recovered from broiler chicken were classified into coagulase positive staphylococci (CPS) (40.3%) and coagulase negative staphylococci (CNS) (59.6%). The CPS isolates were identified as MRSA (34.8%) and methicillin sensitive Staphylococcus aureus (MSSA) (65.2%) according to oxacillin resistance by disc diffusion method. The CPS isolates showed the highest rate of resistance to trimethoprim/sulphamethoxazole (100% and 93.3% for MRSA and MSSA respectively), erythromycin (100% and 93.3% for MRSA and MSSA respectively), oxacillin and cefoxitin (100%, 87.5% MRSA and 0%, 6.7% MSSA respectively), ceftriaxone (87.5% and 73.3% for MRSA and MSSA respectively) and amoxicillin (75% and 40% for MRSA and MSSA respectively). Moreover, the CNS showed resistance against trimethoprim/sulphamethoxazole with 85.3%, followed by 79.4% erythromycin, 55.9% ceftriaxone, 47% cefoxitin, 47% amoxicillin, and oxacillin (44%). PCR assay revealed that four (80%) of five MRSA isolates were harbored mecA gene. The screening of mecA, dfrA and ermC resistant genes was done on plasmid and chromosomal DNA of four MRSA isolates. All of them were chromosome linked genes, but none of these resistant genes were detected on plasmid DNA. All examined isolates (100%) contained ermC gene. In addition, the dfrA gene was detected in 2 (50%) out of the 4 isolates.

Brazilian Journal of Biology

The current study describes the presence of Bacillus cereus (B. cereus) in contaminated foods of ... more The current study describes the presence of Bacillus cereus (B. cereus) in contaminated foods of animal source and ready for human consumption with highlighting on their virulence contributing factors by detection of its virulence genes in addition to identification of their sequencing. Three hundred sixty food samples categorized as (228) meat products and (132) milk products were examined for B. cereus isolation and all of these isolates were confirmed by biochemical tests. Eighteen strains obtained from different food samples were examined for the attendance of a number of virulence genes (nheA, cytK, entFM, bceT and hblC genes) using uniplex PCR method. Furthermore, the B. cereus strains were valued for the sequencing of described genes. Generally 24.44% (88/360) food samples classified as 11.11% (40/360) meat products and 13.33% (48/360) milk products carried B. cereus according to cultural and biochemical properties, with geometric mean (1.5×107±0.15 CFU/g or mL) . The highest...

Environmental Science and Pollution Research, 2022

Listeria monocytogenes (L. monocytogenes) is frequently detected in ruminants, especially dairy c... more Listeria monocytogenes (L. monocytogenes) is frequently detected in ruminants, especially dairy cattle, and associated with the sporadic and epidemic outbreak of listeriosis in farms. In this epidemiological study, the prevalence, virulence, antibiotic resistance profiles, and genetic diversity of L. monocytogenes in three Egyptian dairy cattle farms were investigated. The risk factors associated with the fecal shedding of L. monocytogenes were analyzed. The L. monocytogenes strains from the three farms were categorized into distinct genotypes based on sampling site and sample type through enterobacterial repetitive intergenic consensus polymerase chain reaction (ERIC-PCR). A total of 1896 samples were collected from animals, environments, and milking equipment in the three farms. Results revealed that 137 (7.23%) of these samples were L. monocytogenes positive. The prevalence of L. monocytogenes in the animal samples was high (32.1%), and the main environmental source of prevalent ...

Pakistan Journal of Biological Sciences

Clostridium perfringens is one of the most widespread pathogen producing toxins related to variab... more Clostridium perfringens is one of the most widespread pathogen producing toxins related to variable pathogenic conditions, particularly food poisoning in humans. Thus, this study described the prevalence, enumeration, toxigenic types and antibiotic susceptibility of C. perfringens strains isolated from minced meat in Egypt as well as the validation of a real-time polymerase chain reaction (PCR) test for the identification of C. perfringens toxin genes. A high prevalence of C. perfringens (98/105, 93.3%) was detected in minced meat samples. The total count of viable C. perfringens in 23 samples was 2.0 × 102 to 4.5 × 102 with a mean value 3.7 × 102 ± 1.07 × 102 CFU/g. The toxin typing of C. perfringens based on lecithinase activity and dermonecrotic reactions in albino guinea pig exhibited 33 (33.7%) as toxigenic strains of C. perfringens type A and 65 (66.3%) as non-toxigenic strains. Antibiotic susceptibility testing of isolates against 15 different antimicrobial agents indicat...

Veterinary Research Communications

Advances in Animal and Veterinary Sciences, 2019

F resh water fish, Oreochromis niloticus (Nile tilapia) and Clarias gariepinus (African catfish),... more F resh water fish, Oreochromis niloticus (Nile tilapia) and Clarias gariepinus (African catfish), is one of the most important protein sources for people in a lot of countries (Iqbal et al., 2012). Aquacultures incorporated into the farming system have been revealed to develop food security with slight external inputs (Wetengere, 2010). However, mortality and sever economic losses amongst the ornamental and food fish farming industries as the chief features of fungal infections were exhibited (Ali, 2015). For example, epizootic ulcerative syndrome (EUS) infection was one of most common disease caused by Aspergillus niger and Aspergillus fumigatu in fresh water fish (Chauhan, 2013). Really, the incidence and diversity of fungi as well as their secondary metabolites in aquatic systems are occupied a worldwide growing interest. Nonetheless, such concern is hindered by the scarce data about aquatic fungi in the investigations (Magwaza et al., 2017). Many of the fungi affected fish are considered opportunists. Fish is attacked when it is immunocompromised or stressed owing to unfavorable environment or subsequent to bacterial in

Veterinary World, Oct 24, 2021

Background and Aim: Escherichia coli is the cause of avian colibacillosis, a significant threat t... more Background and Aim: Escherichia coli is the cause of avian colibacillosis, a significant threat to the poultry industry and public health. Thus, this study investigated the prevalence of E. coli in diseased chicken broilers, pathological effects of these bacteria, and interleukin (IL) gene expression of different serotypes of E. coli (O78, O26, O44, and O55) on experimentally infected chickens.

Materials and Methods: A total of 295 organ samples (liver, lungs, heart, and spleen) from 59 diseased broiler chickens were used for conventional identification of E. coli. Chickens were orally infected with one of the following E. coli serotypes (O78, O26, O44, or O55) and examined for clinical signs, mortality, macroscopic and microscopic lesions, and IL gene expression using real-time quantitative polymerase chain reaction.

Results: E. coli was isolated from 53.2% of broiler chicken organs with a high prevalence in lungs (26.1%). The most prevalent serotypes were O78, O26, O44, O55, O157, and O127 prevalence of 27.8, 22.2, 16.7, 16.7, 5.6, and 5.6%, respectively. In the experimental design, five groups (G1-G5) of birds were established. G1 served as the negative control group, while G2-G5 were challenged orally with E. coli O78, O26, O55, or O44, respectively. Chickens infected with E. coli O78 or O26 showed significant clinical signs in comparison to the other infected birds. Mortality (13.3%) was only observed in birds infected with E. coli O78. Necropsy of dead birds after E. coli O78 infection showed pericarditis, enteritis, airsacculitis, and liver and lung congestion. More severe histopathological changes were observed in intestines, spleen, liver, and lung from chickens infected with either E. coli O78 or O26 than for birds infected with other serotypes. On the 2nd day post-infection, E. coli challenge, particularly with E. coli O78, displayed significantly upregulated levels of ileal IL-6 and IL-8, but ileal IL-10 level tended to be downregulated in comparison to the control group.

Conclusion: This study assessed the application of cytokines as therapeutic agents against infectious diseases, particularly colibacillosis.

Environmental Science and Pollution Research

Pakistan Journal of Biological Sciences