Affiner votre recherche
Résultats 1-7 de 7
Detection of antibiotic resistance and classical enterotoxin genes in coagulase -negative staphylococci isolated from poultry in Poland
2019
Pyzik, Ewelina | Marek, Agnieszka | Stępień-Pyśniak, Dagmara | Urban-Chmiel, Renata | Jarosz, Łukasz S. | Jagiełło-Podębska, Izabella
Introduction: The study sought to characterise antimicrobial resistance among coagulase-negative Staphylococcus (CNS) species recovered from broiler chickens and turkeys in Poland including the presence of 12 antimicrobial resistance genes and five classical genes of staphylococcal enterotoxins. Material and Methods: A panel of 11 antimicrobial disks evaluated the phenotypic sensitivity of the tested strains to antibiotics. Five multiplex PCR assays were performed using primer pairs for specific detection of antibiotic resistance genes and staphylococcal enterotoxin A to E genes. Results: Selected antimicrobial agent susceptibility testing revealed 100% of such in in vitro conditions to cefoxitin among strains of Staphylococcus sciuri and S. chromogenes. The blaZ (for ß-lactam) and mecA (for methicillin resistance) genes were in 58.3% and 27.5% of strains, respectively. Among genes resistant to tetracyclines, tetK was most frequent. Fewer (CNS) strains showed genes resistant to macrolides, lincosamides, and florfenicol/chloramphenicol. Multiplex PCR for classical enterotoxins (A-E) detected the see gene in two S. hominis strains, while the seb gene producing enterotoxin B was found in one strain of S. epidermidis. Conclusion: CNS strains of Staphylococcus isolated from poultry were either phenotypically or genotypically multidrug resistant. Testing for the presence of the five classical enterotoxin genes showed that CNS strains, as in the case of S. aureus strains, can be a source of food intoxications.
Afficher plus [+] Moins [-]Effects of sterilization with hydrogen peroxide gas plasma, ethylene oxide, and steam on bioadhesive properties of nylon and polyethylene lines used for stabilization of canine stifle joints
2012
Gatineau, Matthieu | El-Warrak, Alexander O. | Bolliger, Christian | Mourez, Michael | Berthiaume, Frederic
Objective: To compare effects of sterilization with hydrogen peroxide gas plasma (HPGP), ethylene oxide, and steam on bioadhesive properties of nylon and polyethylene lines used for stabilization of canine stifle joints. Sample: Samples of a 36.3-kg test nylon leader line, 57.8-kg test nylon fishing line, and 2-mm ultrahigh–molecular weight polyethylene (UHMWPE) were used. Procedures: In this in vitro study, samples of nylon leader line, fishing line, and UHMWPE sterilized by use of HPGP, ethylene oxide, and steam or unsterilized samples were used. Bacterial adherence on unsterilized and sterilized samples was tested with Staphylococcus epidermidis and Escherichia coli. Five samples were examined for each line type and sterilization condition, and final colony counts were obtained. Results: Bacterial adherence was significantly affected by method of sterilization for all 3 line types. For most of the samples, bacterial adherence was similar or lower when HPGP sterilization was used, compared with results for sterilization via ethylene oxide and steam, respectively. Bacterial adherence was significantly higher for UHMWPE, compared with adherence for the nylon line, regardless of the sterilization method used. Bacterial adherence was higher for nylon fishing line than for nylon leader line for S epidermidis after ethylene oxide sterilization and for E coli after HPGP and ethylene oxide sterilization. Conclusions and Clinical Relevance: Effects of HPGP sterilization on bioadhesive properties of nylon and polyethylene lines compared favorably with those for ethylene oxide and steam sterilization. Also, nylon line may be a more suitable material than UHMWPE for suture prostheses on the basis of bacterial adherence properties.
Afficher plus [+] Moins [-]Absence of bactericidal effect of focused shock waves on an in-vitro biofilm model of an implant
2012
Madron, Matthew S. | McClure, Scott R. | Griffith, Ronald W. | Wang, Chong
The objective of this study was to evaluate the bactericidal effect of shock waves (SWs) on gram-negative or gram-positive monocultured biofilms grown on an orthopedic implant in vitro. Cortical bone screws were individually cultured with Escherichia coli or Staphylococcus epidermidis to produce a biofilm. In each run of 8 screws, 6 screws were treated with shock waves and then sonicated to disrupt the biofilm. One screw was sonicated only and one was not shock waved or sonicated before sampling for plate count dilutions. Post-treatment serial dilutions and plate counts were done on an aliquot from the vial containing each screw to obtain the number of colony-forming units (CFUs). Shock waves were at a constant energy of 0.15 mJ/mm2. Pulse number and screw orientation were varied. A linear mixed-effects model was used with “treatment” as a fixed effect and “run” as a random effect. Pairwise comparisons of treatments were performed with Tukey-Cramer’s adjustment for P-values. Sonicated plate counts were greater than nonsonicated counts for each run. When all sonicated screws were compared to all nonsonicated screws, the counts were significantly increased (P = 0.0091). For each paired comparison between sonicated and shock wave treatment, the only significant difference was in the S. epidermidis biofilm treated at 2000 pulses in a horizontal position, which increased the post-treatment count (P = 0.0445). No bactericidal effects were seen on monocultured biofilms on cortical bone screws treated with shock waves.
Afficher plus [+] Moins [-]Conjunctival microbial flora of clinically normal pigs
1994
Davidson, H.J. | Rogers, D.P. | Yeary, T.J. | Stone, G.G. | Schoneweis, D.A. | Chengappa, M.M.
Conjunctival swab specimens from healthy pigs were cultured to determine normal microbial population. Four commercial swine operations were selected for study. Pigs of 4 age groups were tested: nursing pigs, nursery pigs, feeder pigs, and sows. Swab specimens were taken from the conjunctival sac of each pig. Bacterial, fungal, and mycoplasmal growth was determined separately. Chlamydia sp was detected by use of an ELISA. Bacteria were recovered from 98% of specimens evaluated. alpha-Streptococcus sp (89%) was the most commonly recovered organism, followed by Staphylococcus epidermidis (39%) and Staphylococcus sp (39%). Mycoplasma sp was not detected in any of the specimens. Chlamydia sp was identified in 28% of all specimens evaluated. These results are similar to reports of normal conjunctival flora in other domestic animals.
Afficher plus [+] Moins [-]Role of an intramammary device in protection against experimentally induced staphylococcal mastitis in ewes
1993
Penades, J.R. | Albizu, I. | Baselga, R. | Marco, J. | Barberan, M. | Amorena, B.
An intramammary device (IMD) was adapted for use in ewes; this device was made of abraded poly. ethylene material (1.7 mm in diameter, 47 mm long) and formed a 15-mm-diameter loop in the gland cistern. The IMD was inserted in 1 gland in each of 43 ewes. A significant (P < 0.0001) increase in milk somatic cell count (SCC) was observed in glands provided with an IMD. This increase was attributable to an increase in neutrophil numbers and was observed during the first 12 weeks after insertion. The IMD had a protective effect against experimentally induced staphylococcal mastitis (Staphylococcus aureus and S epidermidis), although different milk SCC were required for protection from each bacterial species in most ewes (10(6) and 2 X 10(5) cells/ml, respectively). Histologic studies revealed that the IMD induced local squamous metaplasia in the glandular part of the lactiferous sinus. Erythrocytes were found in milk from glands provided with an IMD throughout the studied period (35 days of the 45-day lactation) and, in some cases, blood clots were observed during the first 2 weeks of lactation. Glands with IMD also had lower milk production and quality at 30 and 32 days of lactation. Eight ewes with IMD were studied throughout a subsequent lactation. Milk from the IMD-containing glands had an increase in SCC, as in the previous lactation period; did not contain blood clots or erythrocytes; and had normal composition (similar to that in glands without the IMD).
Afficher plus [+] Moins [-]Effect of bovine herpesvirus-1 or parainfluenza-3 virus on immune receptor-mediated functions of bovine alveolar macrophages in the presence or absence of virus-specific serum or pulmonary lavage fluids collected after virus infection
1990
Brown, T.T. Jr | Shin, K.
The immune receptor-mediated functions of bovine alveolar macrophages (AM) inoculated in vitro with bovine herpesvirus-1 (BHV-1) or parainfluenza-3 (PI-3) virus were tested in the presence or absence of virus-specific antiserum or pulmonary lavage fluids collected from calves 6 days after inoculation with BHV-1 or PI-3 virus. The Fc and C3b phagocytic indices of noninoculated AM, collected from 6- to 16-week-old calves, ranged from 75 to 87 and 59 to 64, respectively, and the binding indices ranged from 5 to 8 and 22 to 28, respectively. Infection of AM with either BHV-1 or PI-3 virus had no significant effect on receptor-mediated phagocytosis or binding, with the exception of a significant (P < 0.05) decrease, from 64 to 46, of the C3b phagocytic index of PI-3 virus-infected AM. The addition of lavage fluids, collected after BHV-1 or PI-3 virus infection, to AM infected with the respective virus caused a significant (P < 0.05) decrease in phagocytic indices with values for the Fc and C3b indices in BHV-1-infected AM decreasing from 81 to 49 and from 47 to 8, respectively, and those for the PI-3 virus-infected AM from 79 to 51 and from 46 to 15, respectively. The binding indices of virus-infected AM increased with the addition of viral lavage fluids, but the only significant (P < 0.05) increase was for C3b binding in PI-3 virus-infected cells, which increased from 33 to 56. Virus-specific serum added to AM infected with the respective virus also caused significant (P < 0.05) decreases in the Fc and C3b phagocytic indices, with those for BHV-1-infected AM decreasing from 81 to 24 and from 47 to 5, respectively, and those for PI-3 virus-infected AM from 79 to 23 and from 46 to 3, respectively. The Fc binding index significantly (P < 0.05) increased with the addition of virus-specific serum from 8 to 34 and from 10 to 42 in BHV-1 and PI-3 virus-infected AM, respectively. The C3b binding index of these AM also increased, but not significantly. Infection of AM with either BHV-1 or PI-3 virus had no significant effect on the phagocytosis of opsonized (OPZ) or nonopsonized (nonOPZ) Staphylococcus epidermidis (SE). The addition of lavage fluids, obtained after BHV-1 infection, to AM infected with BHV-1, significantly (P < 0.05) decreased the percentage of phagocytosis of OPZ-SE from 28 to 21 and had a similar, but less substantial effect, on the phagocytosis of nonOPZ-SE. Lavage fluids collected after PI-3 virus inoculation, added to PI-3 virus-infected AM did not have a notable effect on the phagocytosis of OPZ-SE, but did cause a significant (P < 0.05) decrease in the percentage of phagocytosis of nonOPZ-SE from 25 to 17. The addition of virus-specific serum to infected AM caused significant (P < 0.05) decreases in the percentage of phagocytosis of OPZ-SE and nonOPZ-SE, with the values in the BHV-1-infected AM going from 28 to 11 and 16 to 9, respectively, and in the PI-3-infected AM from 36 to 12 and 25 to 13, respectively. Alveolar macrophages infected with either BHV-1 or PI-3 virus, in the presence or absence of lavage fluids from virus-infected calves or virus-specific serum, killed ingested SE as readily as noninfected AM. On the basis of the findings of this study, we suggest, as with other virus infections, that products of the host antiviral immune response interact with AM infected with BHV-1 or PI-3 virus or cause impaired internalization of receptor-bound particles, resulting in impaired AM antimicrobial functions.
Afficher plus [+] Moins [-]Antibiotic susceptibility of bacteria isolated from the genital system of cows in Al-Hilla, Iraq
2015
Sulake Fadhil Al-Zubaidi
The aim of this study was to investigate the bacteria found in different parts of the genital system in cows and the susceptibility to different types of antibiotics. The genital systems of sixteen cows were collected from Al-Hilla, Iraq slaughterhouse. Isolation and identification of bacteria were made for each part of the genital system and antibiotic susceptibility tests was conducted to the isolated bacteria. The results of this study indicated that there were several types of bacteria present in the genital systems of cows. Different species of bacteria were isolated from the samples including, Escherichia coli (28.97)%, Klebsiella spp. (16.82)%, Salmonella spp. (14.95)%, Proteus spp. (13.08)%, Staphylococcus aureus (11.21)%, Staphylococcus epidermidis (8.41)% and Streptococcus spp. (6.54)%. In vitro susceptibility towards different types of antibiotic indicated high susceptibility of Escherichia coli to antibiotic group impenem and ciprofloxacin, while Klebsiella spp. was found to be most susceptible to ciprofloxacin and amikacin. Both Escherichia coli and Klebsiella spp. showed resistance to piperacillin and tetracycline. It was concluded that Escherichia coli was the most predominant bacteria in genital system of cows and were most susceptible to antibiotic impenem and ciprofloxacin.
Afficher plus [+] Moins [-]