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Access Microbiology 2021serotype A2 is the main bacterial causative agent of ovine mannheimiosis, a disease that leads to substantial economic losses for livestock farmers. Several virulence...
serotype A2 is the main bacterial causative agent of ovine mannheimiosis, a disease that leads to substantial economic losses for livestock farmers. Several virulence factors allow to colonize the lungs and establish infection. Virulence factors can be directly secreted into the environment by bacteria but are also released through outer membrane vesicles (OMVs). In addition, due to the abuse of antibiotics in the treatment of this disease, multidrug-resistant bacterial strains of have emerged. One therapeutic alternative to antibiotics or an adjuvant to be used in combination with antibiotics could be lactoferrin (Lf), a multifunctional cationic glycoprotein of the mammalian innate immune system to which no bacterial resistance has been reported. The aim of this work was to determine the effect of bovine iron-free Lf (apo-BLf) on the production and secretion of proteases into culture supernatant (CS) and on their release in OMVs. Zymography assays showed that addition of sub-MIC concentrations of apo-BLf to cultures inhibited protease secretion without affecting culture growth. Biochemical characterization revealed that these proteases were mainly cysteine- and metalloproteases. The secretion of a 100 kDa metalloprotease was inhibited by sub-MIC concentrations of apo-BLf since this protease was present in the cytoplasm and OMVs but not in CS proteins, as corroborated by Western blotting. On the other hand, proteases produced by caused cleavage of apo-BLf. However, when Lf is cleaved, peptides known as lactoferricins, which are more bactericidal than natural Lf, can be produced. A2 protease-mediated degradation of host tissue proteins could be an important virulence factor during the infectious process of pneumonia in ovines. The mechanism of protease secretion could be inhibited by treatment with apo-BLf in animals.
PubMed: 34816089
DOI: 10.1099/acmi.0.000269 -
The Canadian Veterinary Journal = La... Jan 2022This study compared changes in prevalence and antimicrobial susceptibility of , and in feedlot calves derived from the auction market (AUCT; = 299) and from a...
This study compared changes in prevalence and antimicrobial susceptibility of , and in feedlot calves derived from the auction market (AUCT; = 299) and from a single-ranch source (RANCH; = 300). In the AUCT calves, the prevalence of decreased, whereas increased over the feeding period. The AUCT calves showed an increase in isolates not susceptible to tulathromycin for all bovine respiratory disease (BRD) pathogens, an increase in and isolates not susceptible to oxytetracycline, and an increase in isolates not susceptible to florfenicol. In the RANCH calves, the prevalence of all 3 BRD pathogens was high at feedlot entry and decreased significantly during the study period. In RANCH calves, there was a significant increase in isolates not susceptible to oxytetracycline, tulathromycin, and florfenicol. Surprisingly, there was a significant decrease in isolates that were not susceptible to oxytetracycline, tilmicosin, and tulathromycin.
Topics: Animals; Anti-Bacterial Agents; Bovine Respiratory Disease Complex; Cattle; Cattle Diseases; Drug Resistance, Bacterial; Mannheimia haemolytica; Microbial Sensitivity Tests; Pasteurella multocida
PubMed: 34975167
DOI: No ID Found -
Microorganisms Jun 2021Bovine respiratory disease (BRD) causes high morbidity and mortality in beef cattle worldwide. Antimicrobial resistance (AMR) monitoring of BRD pathogens is critical to...
Bovine respiratory disease (BRD) causes high morbidity and mortality in beef cattle worldwide. Antimicrobial resistance (AMR) monitoring of BRD pathogens is critical to promote appropriate antimicrobial stewardship in veterinary medicine for optimal treatment and control. Here, the susceptibility of and isolates obtained from BRD clinical cases (deep lung swabs at post-mortem) among feedlots in four Australian states (2014-2019) was determined for 19 antimicrobial agents. The isolates were pan-susceptible to all tested agents apart from a single macrolide-resistant isolate (1/88; 1.1%) from New South Wales (NSW). Much higher frequencies of isolates were resistant to tetracycline (18/140; 12.9%), tilmicosin (19/140; 13.6%), tulathromycin/gamithromycin (17/140; 12.1%), and ampicillin/penicillin (6/140; 4.6%). Five isolates (3.6%), all obtained from NSW in 2019, exhibited dual resistance to macrolides and tetracycline, and a further two Queensland isolates from 2019 (1.4%) exhibited a multidrug-resistant phenotype to ampicillin/penicillin, tetracycline, and tilmicosin. Random-amplified polymorphic DNA (RAPD) typing identified a high degree of genetic homogeneity among the isolates, whereas isolates were more heterogeneous. Illumina whole genome sequencing identified the genes (E) and (E)encoding macrolide resistance, (R)-(H) or (Y) encoding tetracycline resistance, and encoding ampicillin/penicillin resistance in all isolates exhibiting a corresponding resistant phenotype. The exception was the tilmicosin-resistant, tulathromycin/gamithromycin-susceptible phenotype identified in two Queensland isolates, the genetic basis of which could not be determined. These results confirm the first emergence of AMR in and from BRD cases in Australia, which should be closely monitored.
PubMed: 34204544
DOI: 10.3390/microorganisms9061322 -
Data in Brief Aug 2019Proteomics data have been obtained from experimental mastitis in ewes after intramammary challenge with . Animals were sampled before and sequentially after challenge;...
Proteomics data have been obtained from experimental mastitis in ewes after intramammary challenge with . Animals were sampled before and sequentially after challenge; blood plasma and milk whey samples were produced and were subjected to proteomics evaluation by means of two-dimensional gel electrophoresis and MALDI-TOF mass spectrometry. Full protein maps and differential proteomics in sequential samples from blood plasma and milk whey of experimental ewes were presented. Post-challenge, 33 and 89 proteins were identified with differential abundance in blood plasma and milk whey, respectively. Also, 74 proteins were identified with differential abundance between the inoculated and contralateral glands. The data provide further insight in the pathogenesis of mastitis in sheep and indicate potential biomarkers for the disease. The data are further discussed in the research article "Differential quantitative proteomics study of experimental mastitis in sheep" [1].
PubMed: 31384649
DOI: 10.1016/j.dib.2019.104259 -
Journal of Veterinary Internal Medicine 2015Mannheimia haemolytica is an important etiological agent in bovine respiratory disease.
BACKGROUND
Mannheimia haemolytica is an important etiological agent in bovine respiratory disease.
OBJECTIVES
Explore risk factors for recovery of susceptible and resistant M. haemolytica in feedlot cattle and explore associations with health outcomes.
ANIMALS
Cattle (n = 5,498) from 4 feedlots sampled at arrival and later in feeding period.
METHODS
Susceptibility of M. haemolytica isolates tested for 21 antimicrobials. Records of antimicrobial use and health events analyzed using multivariable regression.
RESULTS
M. haemolytica recovered from 29% of cattle (1,596/5,498), 13.1% at arrival (95% CI, 12.3-14.1%), and 19.8% at second sampling (95% CI, 18.7-20.9%). Nearly half of study cattle received antimicrobial drugs (AMDs) parenterally, mostly as metaphylactic treatment at arrival. Individual parenteral AMD exposures were associated with decreased recovery of M. haemolytica (OR, 0.2; 95% CI, 0.02-1.2), whereas exposure in penmates was associated with increased recovery (OR, 1.5; 95% CI, 1.05-2.2). Most isolates were pan-susceptible (87.8%; 95% CI, 87.0-89.4%). AMD exposures were not associated with resistance to any single drug. Multiply-resistant isolates were rare (5.9%; 95% CI, 5.1-6.9%), but AMD exposures in pen mates were associated with increased odds of recovering multiply-resistant M. haemolytica (OR, 23.9; 95% CI, 8.4-68.3). Cattle positive for M. haemolytica on arrival were more likely to become ill within 10 days (OR, 1.7; 95% CI, 1.1-2.4).
CONCLUSIONS AND CLINICAL IMPORTANCE
Resistance generally was rare in M. haemolytica. Antimicrobial drug exposures in penmates increased the risk of isolating susceptible and multiply-resistant M. haemolytica, a finding that could be explained by contagious spread.
Topics: Animals; Anti-Bacterial Agents; Cattle; Cattle Diseases; Drug Resistance, Multiple, Bacterial; Mannheimia haemolytica; Multivariate Analysis; Pasteurellaceae Infections; Risk Factors; Seasons
PubMed: 25818224
DOI: 10.1111/jvim.12547 -
Nutrients Oct 2021Emerging antimicrobial-resistant pathogens highlight the importance of developing novel interventions. Here, we investigated the anti-inflammatory properties of...
Emerging antimicrobial-resistant pathogens highlight the importance of developing novel interventions. Here, we investigated the anti-inflammatory properties of Fructo-oligosaccharides (FOS) in calf lung infections and in airway epithelial cells stimulated with pathogens, and/or bacterial components. During a natural exposure, 100 male calves were fed milk replacer with or without FOS for 8 weeks. Then, immune parameters and cytokine/chemokine levels in the bronchoalveolar lavage fluid (BALF) and blood were measured, and clinical scores were investigated. Calf primary bronchial epithelial cells (PBECs) and human airway epithelial cells (A549) were treated with , lipopolysaccharides (LPS), and/or flagellin, with or without FOS pretreatment. Thereafter, the cytokine/chemokine levels and epithelial barrier function were examined. Relative to the control (naturally occurring lung infections), FOS-fed calves had greater macrophage numbers in BALF and lower interleukin (IL)-8, IL-6, and IL-1β concentrations in the BALF and blood. However, FOS did not affect the clinical scores. At slaughter, FOS-fed calves had a lower severity of lung lesions compared to the control. Ex vivo, FOS prevented -induced epithelial barrier dysfunction. Moreover, FOS reduced - and flagellin-induced (but not LPS-induced) IL-8, TNF-α, and IL-6 release in PBECs and A549 cells. Overall, FOS had anti-inflammatory properties during the natural incidence of lung infections but had no effects on clinical symptoms.
Topics: Animals; Anti-Inflammatory Agents; Cattle; Disease Models, Animal; Epithelial Cells; Lung; Mannheimia haemolytica; Oligosaccharides; Pasteurella multocida; Pneumonia of Calves, Enzootic
PubMed: 34684515
DOI: 10.3390/nu13103514 -
Veterinary Research Jun 2021Mannheimia haemolytica-induced bovine respiratory disease causes loss of millions of dollars to Canadian cattle industry. Current antimicrobials are proving to be...
Mannheimia haemolytica-induced bovine respiratory disease causes loss of millions of dollars to Canadian cattle industry. Current antimicrobials are proving to be ineffective and leave residues in meat. Antimicrobial peptides (AMPs) may be effective against M. haemolytica while minimizing the risk of drug residues. Cationic AMPs can kill bacteria through interactions with the anionic bacterial membrane. Human β-Defensin 3 (HBD3) and microcin J25 (MccJ25) are AMPs with potent activity against many Gram-negative bacteria. We tested the microbicidal activity of wild-type HBD3, three HBD3 peptide analogues (28 amino acid, 20AA, and 10AA) derived from the sequence of natural HBD3, and MccJ25 in vitro against M. haemolytica. Three C-terminal analogues of HBD3 with all cysteines replaced with valines were manually synthesized using solid phase peptide synthesis. Since AMPs can act as chemoattractant we tested the chemotactic effect of HBD3, 28AA, 20AA, and 10AA peptides on bovine neutrophils in Boyden chamber. Minimum bactericidal concentration (MBC) assay showed that M. haemolytica was intermediately sensitive to HBD3, 28AA and 20AA analogues with an MBC of 50 µg/mL. The 10AA analogue had MBC 6.3 µg/mL which is likely a result of lower final inoculum size. MccJ25 didn't have significant bactericidal effect below an MBC < 100 µg/mL. Bovine neutrophils showed chemotaxis towards HBD3 and 20AA peptides (P < 0.05) but not towards 28AA analogue. Co-incubation of neutrophils with any of the peptides did not affect their chemotaxis towards N-formyl-L-methionyl-L-leucyl-phenylalanine (fMLP). The data show that these peptides are effective against M. haemolytica and are chemotactic for neutrophils in vitro.
Topics: Animals; Bacteriocins; Cattle; Mannheimia haemolytica; Neutrophils; Protein Engineering; beta-Defensins
PubMed: 34112244
DOI: 10.1186/s13567-021-00956-4 -
American Journal of Veterinary Research Nov 2023Evaluate agreement among the antimicrobial susceptibility profiles of Mannheimia haemolytica or Pasteurella multocida obtained by transtracheal wash, nasal swab,...
Agreement of antimicrobial susceptibility testing of Pasteurella multocida and Mannheimia haemolytica isolates from preweaned dairy calves with bovine respiratory disease.
OBJECTIVE
Evaluate agreement among the antimicrobial susceptibility profiles of Mannheimia haemolytica or Pasteurella multocida obtained by transtracheal wash, nasal swab, nasopharyngeal swab, and bronchoalveolar lavage.
ANIMALS
100 Holstein and Holstein-cross bull calves with bovine respiratory disease.
METHODS
Calves > 30 days old with naturally occurring bovine respiratory disease were sampled sequentially by nasal swab, nasopharyngeal swab, transtracheal wash, and then bronchoalveolar lavage. Samples were cultured, and for each antimicrobial, the MIC of 50% and 90% of isolates was calculated, and isolates were categorized as susceptible or not. Categorical discrepancies were recorded. Percent positive agreement and kappa values were calculated between isolates for each of the sampling methods.
RESULTS
Antimicrobial susceptibility varied by pathogen and resistance to enrofloxacin, florfenicol, tilmicosin, and spectinomycin was detected. Minor discrepancies were seen in up to 29% of classifications, with enrofloxacin, penicillin, and florfenicol more frequently represented than other drugs. Very major and major discrepancies were seen when comparing florfenicol (1.9%) and tulathromycin (3.8 to 4.9%) across sampling methods. Some variability was seen in agreement for enrofloxacin for several comparisons (8.3 to 18.4%).
CLINICAL RELEVANCE
Susceptibility testing of isolates from 1 location of the respiratory tract can reliably represent susceptibility in other locations. Nevertheless, the potential for imperfect agreement between sampling methods does exist. The level of restraint available, the skill level of the person performing the sampling, the age and size of the animal, disease status, and treatment history all must be factored into which test is most appropriate for a given situation.
Topics: Humans; Cattle; Animals; Male; Pasteurella multocida; Mannheimia haemolytica; Enrofloxacin; Anti-Bacterial Agents; Cattle Diseases; Respiratory Tract Diseases; Microbial Sensitivity Tests
PubMed: 37558231
DOI: 10.2460/ajvr.23.06.0140 -
Veterinary Microbiology Nov 2021The aim of the investigation was to predict the serotypes of M. haemolytica based on whole genomic sequences with the capsular gene region as target. A total of 22...
The aim of the investigation was to predict the serotypes of M. haemolytica based on whole genomic sequences with the capsular gene region as target. A total of 22 strains selected to have been serotyped and to represent all serotypes were investigated by whole genomic sequencing. The BIGSdb (Bacterial Isolate Genome Sequence Database) was downloaded and installed on a Linux server. Here the sequence database was setup with unique loci at serotype level. The server allows serotypes of M. haemolytica to be predicted from whole genomic sequences and the service is available to the public for free from https://ivsmlst.sund.root.ku.dk.
Topics: Animals; Genome, Bacterial; Genomics; Mannheimia haemolytica; Serogroup; Whole Genome Sequencing
PubMed: 34509701
DOI: 10.1016/j.vetmic.2021.109232 -
TheScientificWorldJournal 2024species are frequently encountered as serious diseases in small ruminants. It is the main cause of respiratory pasteurellosis in sheep and goats of all age groups.
BACKGROUND
species are frequently encountered as serious diseases in small ruminants. It is the main cause of respiratory pasteurellosis in sheep and goats of all age groups.
METHODS
The cross-sectional study was conducted from December 2022 to April 2023 in Haramaya district, eastern Ethiopia, to isolate and identify and and estimate their prevalence, associated risk factors, and antimicrobial sensitivity of isolates in small ruminants using a purposive sampling method. A total of 384 samples (156 nasal swabs from clinic cases and 228 lung swabs from abattoir cases) were collected. STATA 14 software was used to analyze the data. In addition, multivariable logistic regression analysis was performed to assess an association of risk factors.
RESULTS
Out of the 384 samples examined, 164 were positive for pasteurellosis, resulting in a 42.70% prevalence. Similarly, 63 (38.4%) of the 164 positive results were from nasal swabs, while 101 (61.6%) came from lung samples. accounted for 126 (76.82%) of the isolates, while accounted for 38 (23.17%). Of the 63 nasal swab isolates, 33 (37%) were from goats and 30 (42.8%) were from sheep. And 17 (10.89%) and 46 (29.58%), respectively, were and . Of the 46 (40%) of the 101 (44.3%) isolates of the pneumonic lung, samples were from goats, while 55 (48.47%) were from sheep. In this study, the risk factors (species, age, and body condition score) were found to be significant ( < 0.05). isolates evaluated for antibiotic susceptibility were highly resistant to oxacillin (90.90%), followed by gentamycin (72.72%), and penicillin (63.63%). However, the isolates were highly sensitive to chloramphenicol (90.90%), followed by tetracycline (63.63%), and ampicillin (54.54%).
CONCLUSION
This study showed that and are the common causes of mannheimiosis and pasteurellosis in small ruminants, respectively, and isolates were resistant to commonly used antibiotics in the study area. Thus, an integrated vaccination strategy, antimicrobial resistance monitoring, and avoidance of stress-inducing factors are recommended.
Topics: Animals; Pasteurella multocida; Mannheimia haemolytica; Ethiopia; Sheep; Goats; Anti-Bacterial Agents; Cross-Sectional Studies; Microbial Sensitivity Tests; Sheep Diseases; Goat Diseases; Prevalence; Risk Factors; Pasteurella Infections
PubMed: 38655561
DOI: 10.1155/2024/5605552