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Multiplex PCR for simultaneous detection of 3 major fish pathogens incriminated in bacterial septicemic syndrome
2018
Mortada M. A. Hussein | Walid H. Hassan | Aya M. A. El-Wkeel
Fish with bacterial septicemic syndrome (BSS) exhibit very similar clinical signs regardless of the etiological agents. Members of Aeromonas, Pseudomonas, Vibrio, Edwardsiella, Streptococcus and Lactococcus species are considered the most reported bacterial pathogens incriminated in such syndrome. Aeromonas hydrophila, Edwardsiella tarda and Streptococcus iniae are 3 major pathogens share in the BSS associated losses in aquaculture and considered problematic for growth of tilapia and catfish production in Egypt. Therefore, rapid and accurate diagnosis is highly needed for controlling their disease outbreaks, particularly, in mixed infections. In an attempt to elucidate the main causative pathogen, a novel multiplex PCR (m-PCR) was newly designed in this study. The developed m-PCR involves amplifying the three multiple genes in single reaction based upon primers deduced from the regions carrying 16S rRNA, etfA and 16S RNA genes of A. hydrophila (Aeromonas spp.), E. tarda and S. iniae, respectively. Prior to perform m-PCR, individual PCR assays were carried out to adapt suitable laboratory and m-PCR assays conditions. The specificity of the developed m-PCR was confirmed by the fact that only specific fragments were amplified equivalent for 953, 415 and 300 bp corresponding to A.hydrophila, E. tarda and S. iniae, respectively, and that was evident with both extracted DNAs and the bacterial cells. More specifically, these specific bands were obtained also when either the extracted DNAs or the bacterial cells of the three pathogens mixed together in the reaction. The developed m-PCR is accurate, sensitive, fast and simple technique for the simultaneous detection of A. hydrophila (Aeromonas spp.), E.tarda, and S. iniae, three major bacterial pathogens involved in BSS incidence in Egypt.
Afficher plus [+] Moins [-]Genetic analysis of multidrug resistant Salmonella isolated from broiler chickens
2018
Walid H. Hassan | Ahmed H. Abed | Abd El Rady Thabet | Eman A.M. El Nady
Salmonellosis is a major problem for the poultry industry, and this problem represents a critical food safety hazard. Resistance to antimicrobial agents within nontyphoidal Salmonellae is a serious problem. The present study aimed to analyze genetically some β-lactamase resistance genes and some virulence associated genes in Salmonella isolates from broiler chicken. Five hundred samples were collected from diseased broiler chickens of different ages (3-6 weeks) from different farms in Assiut Governorate in Egypt during the period from January 2015 to December 2015. Bacteriological examination showed that 26 Salmonella isolates were recovered with a prevalence rate of 5.2% Serotyping of Salmonella isolates showed that S. Enteritidis S. Typhimurium, and S. Kentuky were identified at rates of 50%, 30.8% and 19.2%, respectively. Results of antibiogram showed that 18 Salmonella isolates (92.3%) were multidrug resistant. All isolates were screened for the presence of 2 β-lactamase resistance genes (blaCTX and blaCMY) as well as 3 virulence genes (stn, invA and hilA) using multiplex PCR. The overall prevalences were 53.9% for blaCTX and 34.6% for blaCMY. Meanwhile, stn, invA and hilA genes were found in 96.2%, 100% and 84.7% of isolates, respectively.
Afficher plus [+] Moins [-]Prevalence of Salmonella Spp in Some broiler farmsin different Egyptian Governorates
2018
H.A. Kaoud | M. A. El-Babbly | K. G. El-Iraqi | M.M. Khalil
This study was conducted to evaluatethe degree of biosecurity level with especial reference to Salmonella Spp as an example to explain the expected causes and risk factors that leads to spread them in poultry flocks in Egypt then studied farms evaluated for the sensitivity of Salmonella isolates to the most common disinfectants used in Egypt. About 300 samples (100 cloacal swabs, 100 liver and intestinal samples, 100 litter samples) were collected from 10 broiler farms with different age (at 0 old day, one week, 2,4 and 6 weeks of age) then the samples were investigated for Salmonella Sppand subsequently identified based on biochemical and serological tests.The obtained results showed that 35 Salmonella species were isolated from 10 broiler poultry houses (25%);(6%) and (4%) from cloacal swab;liver and litter, respectively. Average prevalence of Salmonella spp. was 11.33 % in open broiler houses whether raised Cobb, Ross or Sasso breeds. Salmonella Typhimurium, S. enteritidis and S.Kentucky were the most serovars out of the 35 detected isolates. There was great statistical significant difference in the sensitivity of Salmonella isolates to the most common disinfectants(P<0.05)asVerkon- S® achieved 3 log reduction, after 5-minute,Formalin and Phenique were achieved 3 log reductions against S. entriditisafter one-minute Aldekol Des- Gda® achieved one log reduction after one minute, TH4®,Biosentry® 904 and Iodophoreachieved 2 log reductions after 5 minutes.
Afficher plus [+] Moins [-]Detection of Methicillin-resistant and Biofilm-producing Staphylococcus aureus in Bovine Mastitis
2018
Maha Ibrahim Hamed
The present study was employed to investigate the causative microorganisms responsible for clinical and subclinical mastitis and their antibiotic susceptibility pattern on a private cow farm in Assiut Governorate, Egypt, where a history of recurrent mastitis was the main complaint. In addition, the isolates were investigated for their ability to form biofilm. Forty cows were subjected to a physical examination of the udder and milk using the California mastitis test. Additionally, milk sample collections were obtained, and bacterial specimens were isolated and evaluated for the presence of the mecA gene by PCR. Antibacterial susceptibility assays against the common antibiotics used in the veterinary field were conducted for all isolates obtained. Furthermore, biofilm production by bacterial isolates was detected using the microtiter plate method (MTP) and the activity of specific antibiotics was evaluated against preformed biofilms. About 10% of the examined cows showed clinical signs of mastitis, and 22.2% revealed subclinical mastitis infection when evaluated via the California mastitis test. Staphylococcus aureus (S. aureus) was isolated from all mastitic cows, which indicated that it was the main causative organism for the infection. Streptococcus spp. were isolated from six mastitic animals. Half of the S. aureus isolates were methicillin-resistant, and 83.33% of them were capable of producing biofilm. All Streptococcus spp. isolates were sensitive to all the antibiotics evaluated in the study. S. aureus isolates in the planktonic form were resistant to oxytetracycline and penicillin. In contrast, S. aureus encased in biofilm were resistant to all the antibiotics used in the study. This research detected highly-virulent S. aureus isolates from clinical and subclinical mastitic cases that carry the mecA gene and produce biofilm. The owner is advised to cull the diseased cows to prevent the spread of these virulent isolates to healthy animals. Also, it is advisable not to treat the diseased cows with the antibiotics evaluated in this study as they were found to be ineffective and may potentially contribute to persistence of the infection.
Afficher plus [+] Moins [-]Multi-drug Resistant Enterococcus faecalis isolated from animal and human sources
2018
Ismail Abd El-Hafeez Radwan | Ahmed Osama El Gendey | Mohamed Fathy Mohamed | Nesma Mohsen
This work was planned to investigate the prevalence of antimicrobial resistance of Enterococcus faecalis isolated from animal and human sources. Ten isolates of E. faecalis recovered from urinary tract infections in humans, as well as, ten isolates of E. faecalis were recovered from diarrheic dairy cattle studied for their antimicrobial sensitivity to 7 different antibacterial agents. Antimicrobial sensitivity pattern proved that most isolates were resistant to most of the tested antimicrobial agents. All isolates of human E. faecalis were 100 % resistant to rifamycin, gentamicin and penicillin G. Resistance to amikacin, ciprofloxacin, levofloxacin and vancomycin was 80.0%, 90.0%, 90.0% and 70.0% respectively. However animal E. faecalis were completely (100%) resistant to penicillin G and ciprofloxacin. Resistance to gentamicin, amikacin, levofloxacin, rifamycin and vancomycin was 70.0%, 40.0%, 20.0%, 20.0% and 0.0% respectively. PCR was applied on MDR for detection of aminoglycosides resistance genes. All human E. faecalis isolates were negative for aph(2‖)-Ia, aph(2‖)-Ib, aph(2‖)-Ic and aph(2‖)-Id. 40.0% of isolates were proved to harbour aph(3‖)-IIIa and 10.0% (one isolate) harboured ant(4‖)-Ia. However all animal E. faecalis isolates were negative for aph (2‖)-Ib, aph(2‖)-Ic, aph(2‖)-Id. Two isolates (20.0%) harboured aph(2‖)-Ia and ant(4‖)-Ia and four isolates (40.0%) harboured aph(3‖)-IIIa. In conclusion, the increased antibiotic resistance of E. faecalis isolated from animal and human sources complicate treatment decisions and increase public health hazard.
Afficher plus [+] Moins [-]Effect of Feeding Propolis on Growth Performance of Broilers
2018
Rasha Ibrahim Mohamed | Gamal M.M. Mosaad | Hala Y. Abd El-wahab
An experiment was conducted to investigate the effect of propolis on broiler performance, carcass characteristics and blood parameters. The experiment was carried out with a completely randomized design of 4 treatments, supplemented with propolis at the rate of 0, 1, 2, and 3 mg/kg diet for 6 weeks. The results indicated that birds diet supplementation with propolis increased body weight (P<0.05), decreased feed intake and improved feed efficiency during the experiment. Carcass traits did not show significant differences for the treatments, with the exception of dressing percentage. The serum total protein and globulins were significantly (P<0.05) increased and the serum cholesterol and triglycerides were significantly (P<0.05) decreased in propolis supplemented broilers. No significant differences were observed in hematological parameters among the different groups. It could be concluded that dietary inclusion of propolis to poultry diets had a positive effect on growth performance and improved the immune response by elevating blood globulins level. Also, it decreases blood cholesterol and triglyceride levels.
Afficher plus [+] Moins [-]Serological and molecular characterization of recent lumpy skin disease virus isolates from naturally infected previously vaccinated cattle in Egypt
2018
Tamam, S.M. | El-Shereif, N.M. | Shokier, K.A
lumpy skin disease virus (LSDV) was isolated, from naturally infected cattle that have a history of previous vaccination with live attenuated sheep pox virus (SPV) vaccine. The virus was isolated on chorio-allantoic membranes (CAM) of embryonated chicken eggs (ECE) and Madin Darby Bovine Kidney Cells (MDBK) and identified by agar gel precipitation test (AGPT) and immunofluorescent antibody technique (IFA). Characteristic pock lesions and intracyptoplasmic flourescene granules are identified respectively. Molecular characterization using polymerase chain reaction (PCR) using specific primer for G-Protein Coupled Chemokine Receptor Gene of LSDV isolates specific amplified product 554 bp. Sequence analysis revealed tow new isolates of LSDV.
Afficher plus [+] Moins [-]Evaluation of Crestar® and modified Crestar programs for timed insemination in lactating Egyptian buffaloes (Bubalus bubalis) under intensive production system
2018
M. M. Hussein | K. Amen | A. F. Abdel-Moghney
The current study was conducted on a total of 204 Egyptian, lactating buffalo cows. These animals were in the second or third parity, of good body condition scores and apparently healthy. The animals were raised in intensive production system on a private farm. The buffalo cows were allotted into three groups, two of these groups were experimental and the third was a control group. The first experimental group included 30 buffalo cows were undergo ovulation control by Crestar® a subcutaneous ear implant ( 3mg norgestamet ) plus Crestar® injection i.m. ( 3mg norgestamet + 5mg estradiol valerate ) at zero day. At the 7th day of implantation, PGF2α was injected i.m., then Crestar® implant was removed at the 9th day with injection of PMSG 400 iu. Timed insemination was conducted 56 hrs later. The second experimental group (24 buffalo cows) was treated by the same program, moreover they injected with GnRH at the time of insemination .The third group (150) buffalo cows was bred naturally and used as a control group. For serum progesterone assay blood samples were collected from the animals of the two experimental groups at day 0, 7 and 9 of the Crestar program. The buffalo cows of the experimental groups were closely observed for estrus signs and were rectally palpated at the time of insemination for detection of the internal estrus changes. At day 50 post insemination all animals were rectally palpated for pregnancy diagnosis. The result of the current study revealed that the visibility of estrus signs were 20 %, 16.7% and 22 % for the first, second and third group respectively. Pregnancy rate was much higher in the second group associated with the injection of GnRH at the time of insemination. Two animals of the second group were carrying twins (11 %). Serum level of progesterone was significantly higher in the 7thday in comparison with those recorded for 0 and 9th day.
Afficher plus [+] Moins [-]Occurrence of some pathogenic microorganisms in kareish cheese and their public health significance
2018
G. M. Hassan | Samia I. Afify
A number of 50 Ardeola ibis ibis birds were found harboring six nematodes species; Tetrameres species, Microtteramere species, Synhimantus invaginatus, Synhimantus equispeculatus, Ascaridia species, Paracamallanus species,and five species of trematodes; Euclinostomum heterostomum, Nephrostomum ramosum, Apharyngostrigea ibis, Apatemon gracilis and Centrocestus armatus. The most common infection by nematodes was (46%) in which highest infection rate Synhimantus invaginatus recorded (30 %) while the trematode infection was (24 %) and Apatemon gracilis was the most prevalent (16 %). Experimental infection of buff backed heron by encysted metacercaria (EMC) and exysted metacercaria (ExMC) of Clinostomum complanatum from freshwater fish Tilapia nilotica, resulted in adult worms formed after 6 days. Where the infection by EMC recorded higher worm burden (14-18 worm) and hatching percent (78%) while the infection by ExMC gave lower worm burden (7-10 worm / bird ) and hatching (48 %). In the present study, it is worthy to mention that buff backed heron act as final host model for Clinostomum complanatum and this will be helpful in further biological and immunological studies for this trematode to decrease its economic losses in fish intermediate host.Fifty random samples of Kareish cheese were collected from different localities in Bani-suef Governorate. All samples were examined chemically for acidity, salt and moisture percent and bacteriologicaly for the presence of Escherichia coli, Staphylococcus aureus, Enterococci, Bacillus cereus, Clostridium perfringens, Yersinia enterocolitica, Salmonella and Shigella species. The obtained results revealed that the mean values of acidity, salt and moisture % were 1.63 ± 0.095,3.55 ± 0.299 and 58.54 ± 0.599 in the examined kareish cheese samples, respectively.Escherichia coli, Staphylococcus aureus, Enterococci, Bacillus cereus, Clostridium perfringens were recovered from 16 (32%), 12(24%), 46 (92%), 25 (50 %) and 3 (6%) with a mean value of 4.86x102 ±4.21x10 2, 4.84x 10 5 ± 2.91x10 5, 3.74x10 6±1.55x10 6, 7.08x10 4±2.61x10 4 and 9.5x10 1 ± 7.37x10 1 of the examined samples , respectively. Yersinia enterocolitica could be isolated from 12% of the examined samples. Salmonella and Shigella species could not be detected in any of the examined samples. The isolated Escherichia coli were examined for serological identification, Enterotoxigenicity and the susceptibility of the isolated serovars to various chemotherapeutic agents. The public health significance and economical importance of the isolated organisms and the recommendations to be followed in the processing, handling and storage of such dairy product were discussed
Afficher plus [+] Moins [-]Physicochemical and bacteriological status of retail-marketed shrimps and crabs in Beni-Suef, Egypt
2018
Fatma H.M. Ali | Abdelrahim H.A. Hassan | Gehan M. Oaf | Ahmed A. Elmasry
A total of a hundred and twenty samples of crustaceans, 60 samples of shrimp (30 peeled & 30 unpeeled shrimps) and 60 samples of local chilled crab were collected from Beni-Suef markets. Collected samples were evaluated by the physicochemical deteriorative criteria (pH and TVB-N), the bacterial load determination (mesophilic count, psychrophilic count, Staphylococcus aureus count and MPN of coliforms, faecal coliforms and E. coli), and isolation and identification of specific pathogens (E. coli, and Staphylococcus aureus). All fresh and frozen seafood samples were judged as safe food from the microbiological point of view. The total mesophilic, psychrophilic and S. aureus for all examined seafood samples lies within the standard permissible limits recommended by national and international agencies. The suggestive measure for produce high-quality shrimp & crab was recommended.
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