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Emergence of antimicrobial resistance (AMR) among fish bacterial pathogens is one of the major global public threats. Attempts are being made to develop novel alternatives as a promising approach to combat multidrug resistance disease-causing bacteria. Natural antimicrobials such as essential oils (EOs) are a potential unique strategy to treat bacterial infections with a reduced risk of resistance developing. This study aimed to evaluate the antimicrobial activity of some essential oils (EOs) namely, cinnamon (Cinnamomum zeylanicum), clove (Syzygium aromaticum), Peppermint (Mentha piperita), and black cumin (Nigella sativa) against some fish pathogens implicated with aquaculture disease outbreaks like Aeromonas hydrophilia, Pseudomonas fluorescence, Photobacterium damselae and Streptococcus agalactiae using agar well diffusion assay. We found significant differences on the antibacterial activity depending on the type of essential oils and bacterial strain. Among all the tested EOs, cinnamon essential oil (CEO) was shown to be the most effective with minimum bactericidal concentration (MBC) ranged from 0.0156-0.125 ml/ml. As a result, it was selected for our in vivo investigations. We next aimed to investigate the effects of dietary CEO on growth performance, disease resistance and immune response of fish. A total of 150 striped catfish (Pangasianodon hypophthalmus) were fed with different levels of CEO (0, 1.50, 2.0, 2.50, and 3.0 mL/kg diets) (assigned as control, Diet 1, Diet 2, Diet 3 and Diet 4) for 60 days. Compared to control, fish fed with graded levels of dietary CEO showed significant (P < 0.05) increase in final body weight, weight gain %, and specific growth rate particularly at fish group fed diet 3. Of interest, there were no significant differences (P > 0.05) in feed conversion ratio and survival rates among control and CEO-supplemented groups. Moreover, we found significant (P < 0.05) increases in plasma lysozyme activity and total IgM levels in a dose dependent manner with dietary CEO supplementation. After feeding trials, we investigated their potential to defend striped catfish against A. hydrophila challenge. Fish fed control diet had the highest mortality rates; in contrast, fish fed diets supplemented with CEO had higher levels of resistance to the bacterial infection, with the lowest mortality rates in the fish group fed diet 3. Overall, these findings showed that EOs exhibit a great potential to be used as antimicrobial agents against fish pathogens. Moreover, dietary administration of CEO, particularly at 2.5 ml/kg feed, can be regarded as a promising component for improving growth, immunological responses, and potential alternatives to conventional antimicrobials for control of microbial infections in fish. [ABSTRACT FROM AUTHOR]

Bacterial diseases are one of the most challenging issues facing aquaculture sector. Pseudomonas aeruginosa (P. aeruginosa) has been regarded as one of the most significant threats to the fishing industry, which also affects public health. We aimed to elucidate the occurrence and antibiogram profile of P. aeruginosa recovered from Nile tilapia (Oreochromis niloticus) and smoked herring (Clupea harengus) with emphasis on their antibiotic resistance genes (blaTEM, blaSHV, blaOXA-1 and ampC) and virulence determinant genes (oprL and toxA). A total of 150 fish samples (110 diseased Nile tilapia, and 40 smoked herring) were collected randomly from retails of Gharbia Governorate, Egypt. The retrieved isolates were phenotypically characterized using standard methods of culturing and biochemical tests. Then, verified using molecular assay, 16S rRNA gene was detected in 100% of the tested isolates. The overall incidence of P. aeruginosa was 33.3%, out of which 45% from smoked herring and 29% from Nile Tilapia. The occurrence of P. aeruginosa in various infected organs of O. niloticus showed that the gills were the most obviously infected organ followed by kidney, liver, and spleen, respectively. A significant difference (P< 0.05) was noticed in the distribution of P. aeruginosa among O. niloticus internal organs. The phenotypic susceptibility to nine commonly used antimicrobial agents was detected using disc diffusion assay. The tested strains were extremely susceptible to ciprofloxacin, amikacin, and imipenem, whereas exhibited remarkable resistance to oxacillin, cefpodoxime, amoxicillin with clavulanic acid, ceftriaxone, and nalidixic acid. Interestingly, 100% of P. aeruginosa isolates were multiple antimicrobial resistant (MAR). Three resistance phenotypes profiles were identified with MAR index ranged from 0.4-0.5. Screening for antibiotic resistance genes revealed a diversity of β-lactamases in P. aeruginosa isolates, with blaTEM being the most dominant gene (100%), followed by blaSHV, and ampC with a total prevalence of 66.6% to all of them. The identified antimicrobial resistance phenotypes and genotypes were found to be significantly correlated. Subsequently, the distribution of virulence determinants in these strains was identified. These isolates had 100% prevalence of oprL and toxA virulence genes. In conclusion, the emergence of MDR P. aeruginosa in fish particularly ESBL and AmpC beta-lactamases producers could pose a potential health hazard to consumers. Thus, antimicrobial susceptibility must be continuously monitored to assess potential risks to human health. Ciprofloxacin, amikacin, and imipenem were the most efficient antibiotics for treatment of the identified P. aeruginosa, ESBL and AmpC beta-lactamases producers.blaOXA-1 [ABSTRACT FROM AUTHOR]

The antibacterial activity of zinc oxide nanoparticles (ZnO NPs) has received significant attention worldwide due to the emergence of multidrug-resistant microorganisms. Shiga toxin-producing Escherichia coli is a major foodborne pathogen that causes gastroenteritis that may be complicated by hemorrhagic colitis or hemolytic uremic syndrome. Therefore, this study aimed to evaluate the antimicrobial effect of ZnO NPs against E. coli O26 and its Shiga toxin type 2 (Stx2). Multidrug resistance phenotype was observed in E. coli O26, with co-resistance to several unrelated families of antimicrobial agents. Different concentrations of ZnO NPs nanoparticles (20 nm) were tested against different cell densities of E. coli O26 (108, 106 and 105 CFU/ml). The minimum inhibitory concentration (MIC) value was 1 mg/ml. Minimum bactericidal concentration (MBC) was 1.5 mg/ml, 2.5 mg/ml and 3 mg/ml, respectively, depending on ZnO NPs concentrations and bacterial cell density. Results showed a significant (P≤0.05) decrease in Stx2 level in a response to ZnO NPs treatment. As detected by quantitative real-time PCR, ZnO NPs down-regulated the expression of the Stx2 gene (P≤0.05). Moreover, various concentrations of ZnO NPs considerably reduced the total protein content in E. coli O26. There was a significant reduction in protein expression with increased ZnO NPs concentration compared to the non-treated control. Scanning electron micrographs (SEM) of the treated bacteria showed severe disruptive effects on E. coli O26 with increasing ZnO NPs concentration. The results revealed a strong correlation between the antibacterial effect and ZnO NPs concentrations. ZnO NPs exert their antibacterial activities through various mechanisms and could be used as a potent antibacterial agent against E. coli O26. [ABSTRACT FROM AUTHOR]

Marine microorganisms are conceded as a rich source for bioactive metabolites. However, the microbial diversity of marine ecosystem still needs to be explored. The aim of this study was to isolate and characterize a marine bacterium with antimicrobial activities. Samples of seawater, sediment and algae were collected from the marine coast of Alexandria, Egypt. Twenty two isolates were screened for their ability to produce antimicrobial agent(s). Four isolates from sediment samples showed antibacterial activity against Salmonella enterica. Based on morphological characterization, biochemical and molecular examination, the potent antimicrobial producer was identified as Bacillus amyloliquefaciens AMM. It showed inhibition zone of 10mm on optimized marine nutrient broth culture medium, The immobilized process was performed using the pumice stones it increased the antimicrobial activity twice (20mm) compared to the free cells (10mm). The n-Butanol secondary metabolites of the marine Bacillus amyloliquefaciens AMM (125ppm) showed extensive antibacterial activity against different pathogenic bacteria; Vibrio parahemolyticus Staphylococcus aureus, Pseudomonas aerogenosa, Escherichia coli and Salmonella enterica the inhibition zones were10, 7, 12, 14 and 24mm, respectively. The biotoxicity test of the produced anti-salmonella agent using Artemia salina showed a LC50 of 794.3 ppm. The GC-MS analysis of this study showed the main chemical components of the n-butanol extracted secondary metabolites of Bacillus amyloliquefaciens AMM were Cholestan-3-ol-2-methylene-, (3á,5à)-, Cyclopentanemethylamine, 2-isopropylidene-N, N,5-trimethyl, 1,2,3-Propanetriol-Triacetate, Formic acid-3,7,11-trimethyl-1,6,10-dodecatrien-3 ester and 9-Octadecenoic acid with about 80% of the total area. In addition, the FTIR analysis showed the presence of many active functional groups in these obtained secondary metabolites. [ABSTRACT FROM AUTHOR]

This study was conducted for isolation and identification of Streptococcus iniae from Oreochromis niloticus fish farms using traditional and molecular PCR techniques. Forty-seven isolates of Streptococcus were recovered from 232 fish samples from successive 4 seasons during 2015. Summer showed the highest prevalence with 34.9%. S. iniae was identified as the causative agent for streptococcosisin 3 seasons by PCR using S. iniae specific-16S rRNA primers. Experimental infection was performed to determine the pathogenicity of S. iniae for O.nloticusand the best antibiotics to be used for treatment of streptococcosis. S. iniae caused 70% mortalities in experimentally infected fish. Several histopathological alterations were observed in the liver, spleen, kidney and gills of the infected fish. The most effective antibiotics for treatment were Ampicillin with no mortalities, followed by Penicillin and Tetracycline with 10% mortality for both. [ABSTRACT FROM AUTHOR]

Bacteriological examination of 250 faecal swab samples collected from diarrheic, apparently healthy and freshly dead rabbits acquired from commercial fattening farms in different localities from Alexandria governorate (Egypt) showed that 152 samples (60.8 %) were positive for Escherichia coli (E. coli) isolation. The prevalence of E. coli was 57.43% in apparently healthy rabbits, 70.12% in diarrheic rabbits and 53.23% in freshly dead rabbits. Twenty E. coli isolates were serologically identified as O146 (n= 4), O158 (n= 4), O44 (n= 4), O125 (n= 3), O169 (n= 2), O148 (n= 2) and O157 (n= 1). Antimicrobial susceptibility to gentamycin (CN), tetracycline (T), doxycycline (DO), streptomycin (S), neomycin (N), ciprofloxacin (CIP), Sulphamethoxazole-Trimethoprim (SXT), amoxicillin (AX) and Norofloxacin (NOR) was 88.57%, 22.86%, 51.43%, 56.71%, 22.86%, 51.43%, 48.57%, 28.57% and 71.43%, respectively. While all of the isolates were resistant to ampicillin (AM) and amoxicillin+clavulanic acid (AMC). Conventional polymerase chain reaction for detection of most virulence genes (eaeA, Stx1, LT, cnf1) revealed that two E. coli serotypes O148 and O44 expressed intimin gene and the Stx1 gene, while none of the serotypes expressed LT and cnf1 genes. The finding of virulent multidrug resistant and enterohaemorrhagic E. coli (EHEC) serotypes poses serious health hazard for both rabbits and contact human. [ABSTRACT FROM AUTHOR]

The cocirculation of H5N1 and H9N2 avian influenza viruses in birds in Egypt provides reassortment opportunities between these two viruses. However, little is known about the emergence potential of reassortants derived from Egyptian H5N1 and H9N2 viruses and about the biological properties of such reassortants. To evaluate the potential public health risk of reassortants of these viruses, we used reverse genetics to generate the 63 possible reassortants derived from contemporary Egyptian H5N1 and H9N2 viruses, containing the H5N1 surface gene segments and combinations of the H5N1 and H9N2 internal gene segments, and analyzed their genetic compatibility, replication ability, and virulence in mice. Genes in the reassortants showed remarkably high compatibility. The replication of most reassortants was higher than the parental H5N1 virus in human cells. Six reassortants were thought to emerge in birds under neutral or positive selective pressure, and four of them had higher pathogenicity in vivo than the parental H5N1 and H9N2 viruses. Our results indicated that H5N1-H9N2 reassortants could be transmitted efficiently to mammals with significant public health risk if they emerge in Egypt, although the viruses might not emerge frequently in birds. [ABSTRACT FROM AUTHOR]

The presence of E. coli in fresh-marketed fish indicates recent contamination and is usually attributed to infected handlers or storage on contaminated ice. E. coli may be transmitted to human during handling of fish or consumption of raw or under cooked fish. Human infection (foodborne illnesses) range from mild diarrhea to life threatening hemorrhagic colitis (HC), haemolytic uremic syndrome (HUS). In this study, 200 fish samples from gills, musculature, surface and intestine, 100 water samples and 100 hand swabs from sellers' hand were collected from Kafrelzyate and Tanta retail markets in Gharbiya. The samples were examined for the presence of E. coli. Forty-four samples (8 gills, 3 musculature, 8 surface, 9 intestine, 9 water and 7 hands of sellers) were positive to E. coli. The identification was carried out by both biochemical methods and PCR. The 44 isolates were tested for antimicrobial resistance using 10 antimicrobial discs and the results revealed multiple antimicrobial resistance. Serological identification of the isolates showed the presence of O44 (15.9 %), O125 (20.4 %), O172 (13.6 %), O103 (6.8 %) and O119 (18.1 %). The stx1, stx2 and eaeA virulence genes were detected by PCR in the isolates. [ABSTRACT FROM AUTHOR]

Avian influenza viruses are causing sever drawbacks on the poultry industry in Egypt requiring additional approaches together with vaccination to overcome its endemicity. On this study, twelve white Hy-Line layers were immunized with H5N1 and H9N2 viruses. Throughout the experiment (8 weeks), regular blood samples were collected weekly with daily egg collection. The purified IgY was tested for titres and specificity in hens' sera and egg yolk samples using Hemagglutination-inhibition (HI) and neutralization tests (NT). HI test showed that the antibodies titre values against H5N1 and H9N2 increased from the 1st week in the serum and 2nd week in the yolk until reaching a peak at the 4th week in serum and 5th week in the yolk. The peak was maintained over 3 weeks in the yolk of H5N1 and H9N2 and in the serum of H5N1 and over 4 weeks in the serum of H9N2 followed by nonsignificant decrease until the 8th week. The percentage of transfer of H5N1 antibodies ranged from 6.25% to 50% and for H9N2 ranged from 3.12% to 12.5%. NT showed that the neutralization index of H5N1 and H9N2 were toward homologous 3.9 and 5.04, respectively. Cross NT showed no egg protection with 100% death, but with retardation of the death time. In Conclusion, our results revealed the presence of significant titres of purified IgY against H5N1 and H9N2 influenza viruses in eggs and the possible role of egg yolk IgY in neutralization of avian influenza viruses. [ABSTRACT FROM AUTHOR]

This study aimed to estimate Butchers hands and articles as a source of E. coli contamination in poultry meat and slaughterhouses andto estimate the effect of random antimicrobials usage on the antimicrobial susceptibility of the isolated E. coli. A total of 192 samples were collected from four poultry abattoirs in El-Beheira governorate. Samples were collected from butchers' hands, articles, carcass internal and external surfaces. E. coli was isolated and identified by culture, biochemical analysis and PCR. Further the isolates were studied for their antimicrobial susceptibility against 11 commonly used antibiotics in poultry farms. E. coliwas detected in hands (87.5%), articles (81.25%), internal (80.35%) and external (78.57%) surfaces of the carcasses. The highest antimicrobial sensitivity of the isolates was detected to Tobramycin (100%), Cefotaxime (50-75%) and Chloramphenicol (59-66.7%). While, the highest resistance was detected to Penicillin, Sulfamethoxazole and Trimethoprim, (100%), Amoxicillin (93-100%), Cephradine and Doxycycline. Further, multiple antimicrobial resistance was detected. By PCR, 33.3% (2/6) of the samples from the internal surface of the carcasses were positive for the intimin; eaeA gene. Thus, contamination of chicken carcasses in the abattoirs with pathogenic E. coli that resists different antimicrobials poses a challenge for human food and thus human health. The use of antimicrobials as well asapplying hygienic proceduresin abattoirs are clearly a necessity for the production of healthy food. [ABSTRACT FROM AUTHOR]

H9N2 influenza virus has a great potential for causing severe economic loss in ducks especially in backyard ducks. The current study was conducted to isolate H9N2 influenza virus from backyard ducks and preparation of antiserum against isolated H9N2 influenza virus in rabbits and further evaluation by neutralization test. Samples from liver, spleen, brain and lung were collected from clinically infected ducks during 2014 and 2015. The viruses were isolated and propagated by inoculation of 10 days old embryonated chicken eggs via the allantoic sac. The allantoic fluid was harvested and tested for the titration of the HA activity using chicken erythrocytes. Avian influenza virus type A antigen was detected by flu detect strip test. The RNA was extracted from HA-positive allantoic fluid and identified by RT-PCR using specific primers for H9N2 virus. Antiserum against H9N2 virus was prepared in rabbits. The produced antibody was tested and titrated by HI test against H9N2 isolates from ducks and chickens as well as field samples from ducks and H5N1 isolated from chickens. Neutralization test was also done for evaluation H9N2 antibody protective titer. Ten samples from ducks were HA positive with titer values of 2-5 to 2-10. The HA titer of H9N2 isolates from chickens ranged from 2-4 to 2-11. Also, 16 field samples from ducks were HA positive with titer values of 2-3 to 2-7 and the HA titer of H5N1 isolates from chickens ranged from 2-7 to 2-12. The results of RT-PCR showed that the 10 samples from ducks were positive for H9N2 HA gene. The HI results showed complete inhibition of H9N2 isolates from ducks and chickens. HI test for field samples from ducks showed complete inhibition of 16 field samples. On the contrary, HI test for H5N1 isolates from chickens showed no inhibition of 13 isolates using H9N2 rabbit specific antiserum. The neutralization index using H9N2 virus was 2-5. The presence of LPAI H9N2 may add another risk factor to the poultry industry in Egypt together with the endemicity of HPAI H5N1, especially that backyard ducks and chickens are reared in direct contact allowing easy virus transmission and adds more stress to the poultry populations. Further, false negative results for the detection of H5N1 using H9 antibodies should be considered. [ABSTRACT FROM AUTHOR]

Edwardsiella septicemia is a systemic bacterial disease caused by Edwardsiella tarda that is considered one of the most important bacterial microorganisms causing severe economic losses due to morbidity and mortality among wide fish species in many countries. In this study Edwardsiella tarda (E. tarda) was isolated and identified from Oreochromis niloticus fish farms using traditional and molecular PCR techniques using E. tarda specific primers. Fifty-six isolates of E. tarda were isolated from 300 fish samples during spring, summer and autumn. While in winter it couldn't be isolated from 100 samples. The summer season showed the highest prevalence with 28% then the spring season with 18% finally autamn10%. Experimental infection using the isolated E. tarda was performed to determine the pathogenicity in O. niloticus through mortality rate, clinical sings, post mortem lesions and histopathological changes that were observed in the liver, spleen, kidney and gills of the infected fish. The result also showed that there is no significant difference between in vivo and in vitro effect of antibiotic on E. tarda. Norfloxacin showed the highest protection in vivo with 90% survival while Ampicillin showed no protection. These results indicated that the antibiotic of choice for treatment of E. tarda was Norfloxacin. [ABSTRACT FROM AUTHOR]

The protection of the commercially available vaccines was evaluated against two Egyptian variant IBV isolates that was found to be related to IS/885 variant II strain by 86% and 84% respectively in commercial broiler chickens. The protection assessment was detected by clinical signs, gross lesions, detection of viral shedding in tracheal and cloacal swabs, estimation of kidney function tests (Creatinine and Uric acid), detection of specific IBV antibody titer and histopathological examination. No significant protection could be provided against both challenging viruses using the classical live H120, Ma5 vaccines at day 1 and 14 of age respectively. Also no significant protection could be provided using 2 different inactivated vaccines at day 5 of age. The results indicated that the used vaccine strains and the challenging IBV field isolates are not the same protecteotype, therefore, change in the program of field vaccination is required to obtain a relative improvement of protection. [ABSTRACT FROM AUTHOR]

Salmonella enterica serovar Enteriditis (S.Enteritidis) is a food borne pathogen of human causing food-poisoning and sometime deaths. Many methods have been carried out to decrease the population and prevalence of the causative agent, including chemotherapy and disinfection. In this study, in vitro combination between chemotherapy and disinfection was carried out. Three disinfectants [TH4® (combination of quaternary ammonium compound and gluteraldhyde), Povidone Iodine®(iodophore) and Virkon® S(peroxygen compound)] were tested in vitro against S.Enteritidis. The effect of disinfectants, concentration and time of exposure on the survival of S.Enteritidis was investigated.TH4 0.5% (w/v), Virkon S 1% (w/v) and Povidone iodine7.5%(w/v) reduced S. Enteritidis by 99.9%,72% and 87%, respectively. Further, as the disinfectants' concentration decreased, the survival of bacteria increased. Virkon S and Povidone Iodine recorded satisfied result at 10 min exposure time. TH4 recorded high results at 30 min exposure time. The in vitro combination between the three disinfectants and Norfloxacin 10% showed improvement of the inhibitory effect of TH4 and Povidone Iodine, while the inhibitory effect of Virkon S decreased. In addition, formation of macroscopically white precipitation, which interfere with effect of the two (Virkon S and norfloxacin 10%) and lead to bad inhibitory effect on S. Enteritidis. [ABSTRACT FROM AUTHOR]

Methicillin-resistant Staphylococcus aureus (MRSA) is a type of bacteria that is resistant to certain antibiotics including methicillin, oxacillin, penicillin and amoxicillin. Our study investigated the occurrence of Staphylococcus aureus in a total of 95 and 86 sheep and goat, respectively from different healthy conditions (apparently healthy, pneumonia, enteritis and pneumoenteritis) using routine bacteriological identification and antimicrobial susceptibility testing. The results showed that S. aureus in sheep was detected in 25, 31.25, 43.3 and 20 %, in apparently healthy, pneumonia, enteritis and pneumoenteritis cases, respectively from nasal swabs and 12.5,20.8, 16.6 and 17.5 %, respectively from fecal swabs. While in goats, S. aureus was detected in 25, 26, 15.3, 14.2 % in apparently healthy, pneumonia, enteritis and pneumoenteritis cases, respectively from nasal swabs and 12.5, 8.3, 11.5, 14.2 %, respectively from fecal swabs. Further, the isolates were studied for their antimicrobial susceptibility patterns using 9 antibiotics commonly used. S. aureus isolated from nasal or fecal swabs of healthy sheep and goat were 100% resistant to Ampicillin, Amoxycillin and Penicillin, while S. aureus isolated from nasal and fecal swabs of sheep with pneumointeritis were 50 % resistant to Methicillin and Oxacillin. All S. aureus isolates were 100 % sensitive to Ciprofloxacin and Gentamycin making them the drugs of choice for the treatment of different disease conditions caused by S. aureus in sheep and goat. [ABSTRACT FROM AUTHOR]

A total of 153 unsexed day-old-quail chicks, were randomly allocated into three The aim of this study was to compare the effect of different dietary supplements, probiotic (pro), prebiotic (pre), and symbiotic (pro + pre) on the productive performance of broiler chicks. A total of 504 one -day old chicks were divided into 9 dietary treatments with 7 replicate cages per treatment and 8 broiler chicks per cage. The control group (Gp1) had no supplementation. Broiler chicken were given a dose of 1ml of the different treatments at the 3rd day of age; Lactobacillus acidophilus (LBA) (Gp2), LBA and Yeast cell wall (YCW) (Gp3), Enterococcus feaceum (EF) (Gp4), EF and YCW (Gp5), Bacillus subtilis (BS) (Gp6), BS and YCW (Gp7), YCW (Gp8) and LBA+ EF+ BS+ YCW (Gp9). Body weight, body weight gain, feed intake, and food conversion ratios were calculated weekly until the end of the experiment. The results revealed that the symbiotics, specially GP5, that was treated with 1ml of EF and YCW at the 3rd day of age significantly increased the performance of the broiler chicken (p≤ 0.05) recording body weight, body weight gain, feed intake and feed conversion ratio of 2462, 1188, 2129 and 1.796, respectively. [ABSTRACT FROM AUTHOR]

This work was planned to detect and identify Staphylococcus aureus in imported frozen meat (Brazilian and Indian) as well as locally slaughtered (Balady) meat using routine bacteriological examination and PCR. A total of 100 samples from Brazalian meat, 75 samples from Indian meat and 50 samples from Balady meat were analyzed for Staphylococcus aureus. Our results showed that the prevalence of Staphylococcus aureus in Brazilian, Indian and Balady meat was 27%, 26.67 % and 22 %, respectively. Antimicrobial resistances of the S. aureus isolates showed sensitivity to penicillin, rifompion, ampicillin and novobiocin, while resistant to oxacillin, sulphatrimethoprim, vancomycin and Cefotoxin. Further, multiple antibiotic resistances were detected in 98% (57/58) of the isolates. Higher multiple antibiotic resistance index was detected from S. aureus isolates from the three types of meat and different resistance phenotypes were detected. PCR for the detection of the mecA gene of methicillin resistance was positive with the tested oxacillin resistant S. aureus isolates. PCR for the detection of the virulence genes; Sea, Seb, Sec, Sed and See genes, was performed. Sea and Sed genes were negative, while Seb, Sec, and See genes were detected in 16.66%, 33.33% and 50% of the tested isolates, respectively. These results collectively indicate that Brazilian, Indian as well as balady meat can harbor S. aureus with high percentage of resistance to oxacillin and a wide range of multiple antimicrobial resistances. [ABSTRACT FROM AUTHOR]

A total of 10 Staphylococcus aureus isolates were recovered from 117 milk samples which were obtained from 93 dairy cows indifferent farms suffered from clinical mastitis, these isolates were phenotypically characterized and identified based on colony morphology andbiochemical tests. In addition, antibiotic susceptibility pattern of these strains was investigated and a trial to investigate the mechanism of the isolated bacterium to antibiotic resistance by PCR detection of class 1 integron. The milk samples were examined bacteriologically: Thirty-three out of 117 samples (28.2%) were positive for staphylococcus. Ten out of 33 samples (30.3%) were coagulase positive staphylococcus. The S. aureus isolates were highly sensitive to Cephalothin (DF30), Ampicillin/sulbactam (SAM), Methicillin(DP5μg), Amoxicillin-Clavulanic acid (AMC30) and Trimethoprime-Sulphamethaxole (SXT25μg), Susceptibility rates of S. aureus to these antibiotics were: 90, 80, 80, 70 and70%, respectively. Higher resistance was observed to Streptomycin (S10μg), Kanamycine (K30μg), Tetracycline (Te30μg), Erythromycin(E15μg), Cefotasime (CTX30μg), Cefoperazone(CFP75μg), Ampicillin (AMP10μg), Gentamycine (GN10μg), Amoxicillin (AX25μg) and Ciprofloxacin(CIP5μg), Susceptibility rates of S. aureus to these antibiotics were: 30, 30, 30, 30, 40, 40, 40, 40,40 and 50%, respectively. The molecular detection of S. aureus specific sequence gene(Sa), genes encoding clumping factor A(clfA), gene encoding S. aureus protein A (spa)and the class 1 integron using Polymerase Chain Reaction were carried out. A total of 10 Staphylococcus aureus isolates were negative for the presence of class 1 integron but yielded an amplicon size of about107 bp in case of S. aureus specific sequence gene (Sa), an amplicon size of about 638bp in case ofclfA gene. Amplification of the(spa) gene encoding S. aureus protein A was detected in 9 strains out of 10 (90%)and yielded an amplicon size of about 226bp. The data in this study provided an overview on the incidence of staphylococcus aureus in clinical mastitis and the distribution of virulence determinants and antibiotic resistance of these S. aureus strains. [ABSTRACT FROM AUTHOR]

The present study aimed to detect diarrheagenic Escherichia coli in buffalo calves with or without diarrhea, its virulence factors and antibiotic resistant pattern(s) as well as antibiotic resistance genes. Rectal swabs were collected from193 buffalo calves at different ages in El-Behera Governorate (110 and 83 samples from diarrheagenic and non-diarrheagenic calves, respectively). Ninety-five (49.2%) E. coli positive samples were detected from calves with or without diarrhea by culturing and biochemical tests with higher incidence within the first 2 weeks of age. E. coli samples were subjected to antimicrobial disc diffusion susceptibility test by using 11 different antibiotic discs, which are the most commonly used in field treatment of calf diarrhea. High sensitivities (100%) to individual antibiotics as Amoxycillin and clavulonate, Lincospectin and Cefotaxime was detected while only two showed high resistances as oxytetracycline and Sulfamethoxazole trimethobrim with 91.6% and 50.5% resistance, respectively. PCR for identification of E. coli by detection of phoA gene revealed that 100% of the samples were E.coli positive. PCR for detection of E. coli virulence genes; eaeA and tsh as well as the antibiotic resistance genes; tetA(A) and Sul1 was performed. The eae(A), tsh, tetA(A) and Sul1 genes were found in 20%, 100%, 100% and 60% of E.coli samples, respectively. These results collectively indicate that buffalo calves can harbor enteropathogenic E. coli causing diarrhea at different ages. To our knowledge, this is the first report of detecting the tsh gene in E.coli isolated from diarrheagenic buffalo calves. This may raise concerns regarding the real distribution of tsh-positive E. coli in buffaloes, especially calves. Further, the tsh gene is mainly or exclusively detected in the Avian pathogenic E. coli (APEC) raising concerns on the role of buffaloes as a reservoir for pathogenic E. coli. Together, this can pose therapeutic challenge(s) to farm animals as well as zoonotic potential to contact human. [ABSTRACT FROM AUTHOR]

Foot and mouth disease (FMD) is the most contagious disease of mammals and has a great potential for causing severe economic loss in susceptible cloven-hoofed animals. Egypt has a long history of occurrence of FMDV outbreaks, as the country is dependent on importation of live animals and meat from many countries all over the world. The present study was designed for detection, isolation and molecular characterization of FMDV circulating among different regions in Behaira governorate. Thirty-eight tissue samples were collected from clinically diseased cattle and buffalo from different localities of Beheira governorate. Direct detection of FMDV using ELISA revealed that 84.2% of the samples were positive. Molecular characterization showed that 24 samples (75%) were positive for serotype O and eight samples (25%) were positive for serotype SAT2. This indicates the predominance of serotype O FMDV in Behira, Egypt. [ABSTRACT FROM AUTHOR]