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Cytologic and bacteriologic evaluation of tracheobronchial aspirates from clinically normal foals.
1989
Crane S.A. | Ziemer E.L. | Sweeney C.R.
Thirty-eight tracheobronchial aspirates (TBA) were collected from twenty 1 to 6-month-old foals, which were free of clinical signs of respiratory tract or other infectious disease. We collected TBA from 9 of the foals 3 times when they were approximately 8, 16, and 24 weeks old. Aspirates were examined cytologically after staining with modified Wright-Giemsa, Gram, toluidine blue, and prussian blue stains. Aerobic bacterial culturing was performed on all aspirates. Of the 20 initial TBA, 4 (20%) were normal cytologically on the basis of previously defined criteria for TBA from clinically normal horses, 6 (30%) had a high percentage of eosinophils (> 5%), 8 (40%) were classified as indicative of subacute inflammation, and 2 (10%) were classified as indicative of acute inflammation. Nine (45%) were positive for mast cells and none were positive for hemosiderin-laden macrophages (hemosiderophages). Of the 9 foals from which samples were collected at 16 and 24 weeks of age, results were similar, except for an increase in the number of TBA classified as indicative of chronic inflammation (33% and 22% respectively) and the number positive for hemosiderophages (33% and 88%, respectively). One TBA was considered nondiagnostic because of pharyngeal contamination. Culturing of 12 of the 37 aspirates (32%) yielded a potential microbial pathogen. Only 2 were positive cultures from the same foal. The following organisms were isolated: beta-hemolytic Streptococci spp (4), Actinobacillus/Pasteurella spp (4), Rhodococcus equi (2), unidentified nonenteric Gram-negative rod (1), and Escherichia coli (1). Thirty-four of the 37 aspirates (92%) yielded light growth of various organisms considered to be nonpathogenic and normal inhabitants of the upper respiratory tract. It was concluded that the presence of inflammatory cells, eosinophils, and mast cells in the tracheobronchial aspirates from clinically normal foals is a common finding. These cytologic findings were consistent in the samples collected from foals at 8, 16, and 24 weeks of age. It was also concluded that bacteria with recognized pathogenicity can be isolated from TBA from clinically normal foals and were most frequently isolated from 1- to 2-month-old foals or those with cytologic evidence of inflammation, even in the absence of clinical signs of respiratory tract disease.
اظهر المزيد [+] اقل [-]Effects of ampicillin and trimethoprim-sulfamethoxazole on the vaginal bacterial flora of bitches.
1993
Strom B. | Linde Forsberg C.
Vaginal aerobic bacterial flora was studied in 5 healthy bitches before, during, and after a 10-day period of treatment with ampicillin and an equally long period of treatment with trimethoprim-sulfamethoxazole. Blood variables and antimicrobial drug susceptibility also were studied. Bacteria were isolated from all bitches before the first treatment period. Bitches from which only a sparse number of bacteria were isolated had flora that varied from day to day. In most instances when bitches were given an antibiotic to which their vaginal bacterial flora was susceptible, these bacteria were eradicated after only 1 day of treatment. This was true for pasteurellae, streptococci, and, in all but one case, Escherichia coli. Staphylococcus intermedius was more difficult to eradicate, and, although susceptible in vitro, it was unaffected by antibiotic treatment in 1 bitch and it took 7 days to eradicate in another. Eradication of aerobic bacteria in the vagina was total only in the bitch that had sparse flora from the beginning. Bacteria colonized within 0 (in 4/5 bitches) to 4 days after termination of treatment with ampicillin and within 0 (in 4/5 bitches) to 3 days for trimethoprim-sulfamethoxazole. Mycoplasmas emerged during and after both treatment periods, and E coli became apparent during treatment with trimethoprim-sulfamethoxazole. Because mycoplasmas may be genital pathogens in bitches and E coli is a common uropathogen, their appearance should be an argument against widespread use of antibiotics in healthy breeding bitches. Two bitches developed a vaginal discharge during treatment or shortly after. Blood variables did not change during the study, nor did antimicrobial drug resistance of the isolated bacteria.
اظهر المزيد [+] اقل [-]Pharmacokinetics, bioavailability, and in vitro antibacterial activity of rifampin in the horse.
1988
Wilson W.D. | Spensley M.S. | Baggot J.D. | Hietala S.K.
The pharmacokinetics and bioavailability of rifampin were determined after IV (10 mg/kg of body weight) and intragastric (20 mg/kg of body weight) administration to 6 healthy, adult horses. After IV administration, the disposition kinetics of rifampin were best described by a 2-compartment open model. A rapid distribution phase was followed by a slower elimination phase, with a half-life (t1/2[beta]) of 7.27 +/- 1.1 hours. The mean body clearance was 1.49 +/- 0.41 ml/min.kg, and the mean volume of distribution was 932 +/- 292 ml/kg indicating that rifampin was widely distributed in the body. After intragastric administration of rifampin in aqueous suspension, a brief lag period (0.31 +/- 0.09 hour) was followed by rapid, but incomplete, absorption (t1/2[a] = 0.51 +/- 0.32 hour) and slow elimination (t1/2[d] = 11.50 +/- 1.55 hours). The mean bioavailability (fractional absorption) of the administered dose during the first 24 hours was 53.94 +/- 18.90%, and we estimated that 70.0 +/- 23.6% of the drug would eventually be absorbed. The mean peak plasma rifampin concentration was 13.25 +/- 2.70 microgram/ml at 2.5 +/- 1.6 hours after dosing. All 6 horses had plasma rifampin concentrations > 2 microgram/ml by 45 minutes after dosing; concentrations > 3 microgram/ml persisted for at least 24 hours. Mean plasma rifampin concentrations at 12 and 24 hours after dosing were 6.86 +/- 1.69 microgram/ml and 3.83 +/- 0.87 microgram/ml, respectively. We tested 162 isolates of 16 bacterial species cultured from clinically ill horses for susceptibility to rifampin. All strains of coagulase-positive staphylococci, Streptococcus zooepidemicus, Str equi, Str equisimilis, Rhodococcus equi and Corynebacterium pseudotuberculosis were highly susceptible to rifampin (minimal inhibitory concentration [MIC] less than or equal to 0.25 microgram/ml).
اظهر المزيد [+] اقل [-]Alveolar phospholipids of 17-day-old pigs exposed to microorganisms of nonpulmonic origin.
1986
Engen R.L. | Whipp S. | Hummel S.K.
Prevalence of antibiotic-resistant bacteria amongst dogs in Africa: A meta-analysis review
2022
Yaovi, Ayaovi B. | Sessou, Philippe | Tonouhewa, Aretas B.N. | Hounmanou, Gildas Y.M. | Thomson, Deborah | Pellé, Roger | Farougou, Souaïbou | Mitra, Arindam
Antimicrobial resistance (AMR) is a global public health threat for both human and veterinary medicine. Increasing evidence suggests that animals are important sources of AMR to humans; however, most of these studies focus on production animals. In order to determine the pattern of AMR in pets, mainly in dogs in Africa, a meta-analysis was performed with AMR studies conducted in African countries and published between January 2000 and January 2021 in four databases: Medline (PubMed), Scopus, Cab abstract and Google Scholar. Seven bacterial strains, namely Staphylococcus aureus, Escherichia coli, Salmonella spp., Pseudomonas aeruginosa, Streptococcus pyogenes, coagulase-negative Staphylococcus (SNC) and Staphylococcus pseudintermedius were included in this study. A total of 18 out of 234 indexed articles met the study criteria. The results revealed that multiple bacteria were resistant to various commonly used antibiotics including enrofloxacin, ciprofloxacin, gentamicin, amoxicillin, clavulanic acid, cotrimoxazole, streptomycin, tetracycline and chloramphenicol. Concerning multidrug resistance, E. coli strains came first with the highest prevalence of 98%, followed by P. aeroginosa (92%) and Salmonella spp. (53%). In contrast, the overall prevalence of multidrug resistance was low for S. aureus (18%) and S. pseudintermedius (25%). It is therefore urgent to find, as soon as possible, alternatives to replace these antibiotics, which have become ineffective in controlling these bacteria in dogs in Africa. Moreover, further metagenomic studies are needed to describe the full resistome and mobilome in dogs regardless of the bacteria.
اظهر المزيد [+] اقل [-]Identification of bacterial pathogens and determination of their antibacterial resistance profiles in some cultured fish in Turkey
2016
Türe Mustafa | Alp Hüseyin
Introduction: In the present study, some of the commercial fish farms located in the Black Sea region of Turkey, were screened for bacteria between 2012 and 2014.
اظهر المزيد [+] اقل [-]Potential use of allicin (garlic, Allium sativum Linn, essential oil) against fish pathogenic bacteria and its safety for monosex Nile tilapia (Oreochromis niloticus)
2010
M. M. A. Hussein | W. H. Hassan
A study was conducted to investigate the antibacterial activities of allicin, one of the major essential oils of garlic, against some fish pathogenic bacteria as well as the toxic effect of allicin on monosex Nile tilapia (Oreochromis niloticus). Allicin 10% v/v solution in dimethyl sulfoxide (DMSO) was used in this study. The bacterial species investigated were Aeromonas hydrophila, A. caviae, A. sobria, A. veronii, and Streptococcus iniae. The minimum inhibitory concentrations (MICs) of allicin in DMSO against Aeromonas hydrophila was found to be 125 μg/mL, while ranged between 250–500 μg/mL for each of A. caviae, A. sobria, A. veronii. Interestingly, the MIC for Streptococcus iniae was 63 μg/mL. On contrary, allicin exists no bactericidal activity against any of the investigated bacteria. Allicin had high toxic effect on tilapia fingerlings while adult tilapia could tolerate it.
اظهر المزيد [+] اقل [-]Infectious diseases in aquarium ornamental pet fish
2019
Pedro Henrique Magalhães Cardoso | Andrea Micke Moreno | Luisa Zanolli Moreno | Carolina Helena de Oliveira | Francisco de Assis Baroni | Samara Rita de Lucca Maganha | Ricardo Luis Moro de Souza | Simone de Carvalho Balian
Aquarium ornamental pet fish constitute a major segment in the pet industry, with the United States, Europe, and Japan dominating the market. There are approximately 1,500 marine fish species and over 4,500 freshwater fish species commercialized as aquarium ornamental pet fish. Fish are the fourth most common pet present in Brazilian homes. In Brazil, aquarium ornamental pet fish can be marketed and distributed from different parts of the Brazilian territory and the world. Commercialization and circulation of living animals without the use of adequate prophylactic management procedures enables dissemination of a number of agents responsible for infectious diseases. Aquarium pet fish can also carry pathogenic agents, of bacterial, viral, fungal, or parasitic etiology, that may have a zoonotic feature endangering the persons handling the animals. This review presents the main pathogenic infectious agents of bacterial, viral, andfungal etiology that affect aquarium pet fish, as well as the prevention and control measures to ensure sanitary excellence in this segment.
اظهر المزيد [+] اقل [-]Occurrence of Ornithobacterium rhinotracheale in Polish turkey flocks
2022
Kursa, Olimpia | Tomczyk, Grzegorz | Sawicka-Durkalec, Anna
Ornithobacterium rhinotracheale (ORT) causes significant economic losses to the poultry industry around the world. The bacterium often affects poultry as part of multiple infections causing very serious clinical signs that are usually not limited only to the respiratory system. This study’s main objective was the retrospective detection and identification of ORT in turkey flocks. ORT identification was performed in 6,225 samples taken from 133 different flocks between 2015 and 2020. Molecular methods were used, specifically real-time PCR and traditional PCR. We focused on partial 16S rRNA gene sequences of isolates, which were compared with sequences obtained from GenBank. The reaction products were analysed phylogenetically. Molecular methods indicating secondary infections was carried out, and the bacterial composition of the upper respiratory tract was 16S metasequenced for selected flocks to identify any other pathogens. The presence of ORT was detected in 30.83% of samples by real-time PCR and 28.57% by PCR. Phylogenetic analysis of the PCR products from the turkeys samples showed that their sequences resolved into two main genetic groups. Tests for the occurrence of secondary infections showed the presence of Mycoplasma gallisepticum and M. synoviae in some samples but the total absence of Bordetella avium. The upper respiratory tract in turkeys was dominated by two major phyla Firmicutes and Proteobacteria. At the genus level, the genera Ornithobacterium, Mycoplasma, Gallibacterium, Avibacterium, and Escherichia-Shigella were found which may include pathogenic bacteria that can cause clinical symptoms. The results of the analysis of multiple infection carried out in flocks with respiratory signs are probably associated with outbreaks of ornithobacteriosis in turkey flocks in Poland.
اظهر المزيد [+] اقل [-]Prevalence and characterisation of class 1 and 2 integrons in multi-drug resistant Staphylococcus aureus isolates from pig farms in Chongqing, China
2020
Ye, Chao | Hou, Fengqing | Xu, Dongyi | Huang, Qingyuan | Chen, Xia | Zeng, Zheng | Peng, Yuanyi | Fang, Rendong
Integrons are mobile DNA elements that allow for acquisition and dissemination of antibiotic-resistance genes among pig farm-derived bacteria. Limited information is available on integrons of Staphylococcus aureus from pig farms. The aim of this study was to characterise and investigate the prevalence of class 1 and 2 integrons in multi-drug resistant (MDR) S. aureus isolates from pig farms. A total of 724 swabs were collected from 12 pig farms in Chongqing, China, and examined by conventional microbial and molecular methods. In total, 68 isolates were S. aureus, 57 of which were methicillin resistant (MRSA). All 68 isolates were MDR strains and carried integrons, of which 88.2% (60/68) harboured both class 1 and 2. In addition, 85.3% (58/68) of the class 2 integron-positive isolates carried the β-lactam resistance gene (blaTEM₋₁), and 66.7% (40/60) of the class 1 integron–positive isolates carried the aadA1c, aadA1 or dfrA1 gene for respective streptomycin and spectinomycin or trimethoprim resistance. Class 1 and 2 integrons are common among the pig farm-derived S. aureus isolates. On account of their significance for public health, the prevalence of the integrons and their associated resistance genes in pig farm-derived S. aureus isolates should be paid special attention.
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