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Antibiotics (Basel, Switzerland) Oct 2022Fluoroquinolone (FQ) resistance in a major foodborne bacterial pathogen, , derived from cattle has recently become prevalent and poses a significant public health...
Fluoroquinolone (FQ) resistance in a major foodborne bacterial pathogen, , derived from cattle has recently become prevalent and poses a significant public health concern. However, the underlying factors for this increase are not entirely clear. To evaluate the effect of enrofloxacin treatment on FQ-resistance development in , 35 commercial calves were equally divided into five groups (Groups 1-5) and were orally inoculated with FQ-susceptible (FQ-S) . Eight days later, Groups 4 and 5 were challenged with via a transtracheal route to induce a respiratory disease; after 8 days, Groups 2, 3, 4, and 5 were injected subcutaneously with enrofloxacin (7.5 mg/kg for Groups 2 and 4, and 12.5 mg/kg for Groups 3 and 5). Colonization levels by FQ-resistant (FQ-R) and FQ-S in rectal feces were determined via differential culture throughout the experiment. Before oral inoculation with , only five calves were naturally colonized by , four of which were also colonized by FQ-R (three in Group 1 and one in Group 3). Soon after the oral inoculation, almost all calves in the groups became stably colonized by FQ-S (~3-6 log CFU/g), except that the four calves that were pre-colonized before inoculation remained positive with both FQ-R and FQ-S . Following enrofloxacin administration, colonization declined sharply and rapidly in all treated groups to undetectable levels; however, the vast majority of the animals were recolonized by at comparable levels 72 h after the treatment. Notably, no FQ-R was detected in any of the calves that received enrofloxacin, regardless of the drug dose used or disease status of the animals. The lack of detection of FQ-R was likely due to the localized high concentration of the antibiotic in the intestine, which may have prevented the emergence of the FQ-R mutant. These findings indicate that single-dose enrofloxacin use in cattle poses a low risk for selection of de novo FQ-R mutants in .
PubMed: 36290067
DOI: 10.3390/antibiotics11101407 -
Veterinary Microbiology Nov 2022In the veal industry in The Netherlands, each year around 1.2 million "white" veal calves are produced on around 1100 farms. Bovine respiratory disease (BRD) causes...
In the veal industry in The Netherlands, each year around 1.2 million "white" veal calves are produced on around 1100 farms. Bovine respiratory disease (BRD) causes serious health issues in these calves, also resulting in high usage of antimicrobials. To reduce antimicrobial usage, a more targeted treatment regime is needed, for which it is necessary to identify the causative agent. This study aimed at determining associations between pathogens and clinical disease, between prevalence of pathogens and BRD outbreaks, and BRD and performance. A cohort study was conducted involving ten veal farms, in which calf respiratory health was evaluated for the first 12 weeks. Whenever there was an outbreak of BRD, as determined by the farm veterinary surgeon, samples were taken from diseased and control calves through broncho-alveolar lavage. From these samples a broad spectrum of micro-organisms were isolated. Performance data were also collected. A total of 23 outbreaks happened during the 12 week study period, mostly in the first six weeks. BRD associated pathogens found were: BHV1, BPI3V, BRSV, BVDV, Pasteurella multocida, Mannheimia haemolytica, Trueperella pyogenes, Histophilus somni, Mycoplasma bovis, Mycoplasma bovirhinis and Mycoplasma dispar. For most BRD associated pathogens, there was no clear association between presence or prevalence of the micro-organisms and clinical issues. Only T. pyogenes (7.4% in healthy, 14.6% in diseased calves, p 0.013), M. bovis (37.6% and 63.2% respectively, p 0.001) and BVDV (9.9% and 16.9% respectively, p 0.03) were found more often in diseased animals. BPI3V was found in a few early outbreaks, which might suggest involvement in early outbreaks. It appears to be difficult to associate specific pathogens to outbreaks at the species level. BRD is the major reason for treatment with antimicrobials. More specific knowledge about the association between pathogens and health/disease could help to reduce antimicrobial use.
Topics: Cattle; Animals; Cohort Studies; Mannheimia haemolytica; Cattle Diseases; Mycoplasma bovis; Red Meat; Respiratory Tract Diseases
PubMed: 36115247
DOI: 10.1016/j.vetmic.2022.109571 -
The Canadian Veterinary Journal = La... Sep 2022Cattle at high-risk for bovine respiratory disease on entry to western Canadian feedlots are often treated metaphylactically with antimicrobials from the macrolide...
Changes in the phenotypic susceptibility of isolates to macrolide antimicrobials during the early feeding period following metaphylactic tulathromycin use in western Canadian feedlot calves.
Cattle at high-risk for bovine respiratory disease on entry to western Canadian feedlots are often treated metaphylactically with antimicrobials from the macrolide class. High levels of resistance to macrolides have been reported in isolates from clinical samples, but it is less clear whether this trend extends to the broader feedlot population. The objective was to describe near-term [< 40 days on feed (DOF)] changes in the recovery and susceptibility of isolates from healthy feedlot calves after metaphylactic exposure to tulathromycin. Eight cohorts of 100 calves ( = 800) were sampled deep nasopharyngeal swab at entry processing (, before metaphylaxis, at 1 DOF) and again at 13 DOF. Ten calves from each cohort ( = 80) were randomly sampled a third time at 36 DOF. Recovery of isolates across all cohorts increased over the study period, from 33% (95% CI: 26.5 to 40.2%) at 1 DOF to 75% (95% CI: 71.4 to 78.3%) at 36 DOF. A significant shift in the minimum inhibitory concentration (MIC) distribution of tulathromycin from 1 DOF (MIC ≤ 8 μg/mL) to 13 DOF (MIC > 64 μg/mL) was observed. A subset of 36 isolates from 13 DOF screened for macrolide resistance genes multiplex polymerase chain reaction all harbored the and genes. Recovery of at 13 and 36 DOF did not decline in response to metaphylactic use of tulathromycin; conversely, we inferred the potential for rapid inter-pen spread of a macrolide-resistant clone by 13 DOF in 6 of 8 pens under selective pressure from antimicrobial use.
Topics: Animals; Anti-Bacterial Agents; Canada; Cattle; Cattle Diseases; Disaccharides; Drug Resistance, Bacterial; Heterocyclic Compounds; Humans; Macrolides; Mannheimia haemolytica
PubMed: 36060481
DOI: No ID Found -
Frontiers in Microbiology 2022family members obtain iron directly from host proteins or through siderophore-dependent mechanisms. Although expresses different virulence factors, its response to...
family members obtain iron directly from host proteins or through siderophore-dependent mechanisms. Although expresses different virulence factors, its response to growth under iron restriction is unknown. cultured in the presence of 2,2'-dipyridyl, up-expressed an approximately 65 kDa protein and repressed the expression of a 70 kDa protein. MALDI-TOF analysis of those proteins indicated homology with CirA (65 kDa), a protein involved in iron-siderophore acquisition in and a TonB-dependent receptor (70 kDa protein), a protein that binds chicken hemoglobin; however, siderophore production was not detected by chromo azurol S (CAS)-BHI agar determination. This putative siderophore receptor is under Fur control, but not the hemoglobin binding protein, as observed in 12656-12 mutant (Ω 126.13) grown in the presence or not of 2,2'-dipyridyl. The addition of FeCl to the culture medium diminished the growth and biofilm production in approximately 30% and 35%, respectively, in the wild-type strain, but the growth of Ω 126.13 strain was not affected and biofilm production increased in 35%. Ω 126.13 presented lower virulence when it was inoculated to 35-day-old chickens in comparison to the wild-type strain. The induction of more than one iron uptake mechanism could benefit pathogenic microorganisms such as .
PubMed: 36051765
DOI: 10.3389/fmicb.2022.951173 -
Frontiers in Microbiology 2022Bovine Respiratory Disease (BRD) represents a significant burden to the health of feedlot cattle and the profitability of the beef industry in the US. is widely...
Bovine Respiratory Disease (BRD) represents a significant burden to the health of feedlot cattle and the profitability of the beef industry in the US. is widely regarded as the primary bacterial pathogen driving acute BRD. While is most commonly implicated in chronic cases of BRD, this agent's potential role in acute stages of BRD is unclear. Therefore, this study aimed to evaluate potential associations between and during acute BRD in feedlot cattle. Nasal swabs ( = 1,044) were collected over time from feedlot cattle ( = 270) enrolled in an experiment assessing the effect of vaccination for Bovine Respiratory Syncytial Virus (BRSV). Swabs were analyzed for detection of , and BRSV multiplex qPCR assays. Data were analyzed using inverse conditional probability weighted (ICPW) logistic regression models to investigate potential effects of presence on arrival (d0), day seven (d7) and day 14 (d14) post-arrival on prevalence on day 28 (d28) post-arrival, adjusting for the previous history of , BRSV, BRD morbidity, and body weight. The potential association between time-to-BRD detection and presence on d0, d7, and d14 post-arrival, was inferred an ICPW time-to-event model. The presence of in nasal swabs collected on d7 post-arrival was significantly associated with an increase in the prevalence of on d28 (prevalence difference: 45%; 95% Confidence Interval: 31%, 60%; -value < 0.001). Significant time-varying coefficients for presence were detected at d0, d7, and d14 post-arrival in the ICPW time-to-event model (-value < 0.001). The shortest median time-to-BRD detection was 29 days in cattle that were positive on d0, d7, and d14 post-arrival and in those that were positive on d0 and d14 post-arrival. Under the conditions of this study, our findings suggest that may be influencing the respiratory environment during the acute phase of BRD, increasing the abundance of , which could have important impacts on the occurrence of BRD.
PubMed: 35979489
DOI: 10.3389/fmicb.2022.946792 -
Animal Microbiome Aug 2022Bovine respiratory disease (BRD) is caused by interactions among host, environment, and pathogens. One standard method for antemortem pathogen identification in cattle...
BACKGROUND
Bovine respiratory disease (BRD) is caused by interactions among host, environment, and pathogens. One standard method for antemortem pathogen identification in cattle with BRD is deep-guarded nasopharyngeal swabbing, which is challenging, costly, and waste generating. The objective was to compare the ability to recover Mannheimia haemolytica and compare microbial community structure using 29.5 inch (74.9 cm) deep-guarded nasopharyngeal swabs, 16 inch (40.6 cm) unguarded proctology swabs, or 6 inch (15.2 cm) unguarded nasal swabs when characterized using culture, real time-qPCR, and 16S rRNA gene sequencing. Samples for aerobic culture, qPCR, and 16S rRNA gene sequencing were collected from the upper respiratory tract of cattle 2 weeks after feedlot arrival.
RESULTS
There was high concordance of culture and qPCR results for all swab types (results for 77% and 81% of sampled animals completely across all 3 swab types for culture and qPCR respectively). Microbial communities were highly similar among samples collected with different swab types, and differences identified relative to treatment for BRD were also similar. Positive qPCR results for M. haemolytica were highly concordant (81% agreed completely), but samples collected by deep-guarded swabbing had lower amounts of Mh DNA identified (Kruskal-Wallis analysis of variance on ranks, P < 0.05; Dunn-test for pairwise comparison with Benjamini-Hochberg correction, P < 0.05) and lower frequency of positive compared to nasal and proctology swabs (McNemar's Chi-square test, P < 0.05).
CONCLUSIONS
Though differences existed among different types of swabs collected from individual cattle, nasal swabs and proctology swabs offer comparable results to deep-guarded nasopharyngeal swabs when identifying and characterizing M. haemolytica by culture, 16S rRNA gene sequencing, and qPCR.
PubMed: 35964128
DOI: 10.1186/s42523-022-00197-6 -
The Journal of Antimicrobial... Sep 2022Antimicrobial drugs are frequently administered in veal calves, but investigations on associations with antimicrobial susceptibility of bacteria are scarce and convey...
Associations of antimicrobial use with antimicrobial susceptibility at the calf level in bacteria isolated from the respiratory and digestive tracts of veal calves before slaughter.
OBJECTIVES
Antimicrobial drugs are frequently administered in veal calves, but investigations on associations with antimicrobial susceptibility of bacteria are scarce and convey partly contradictory findings. The aim of this study was to investigate associations of antimicrobial use (AMU) during the fattening period with antimicrobial susceptibility shortly before slaughter.
METHODS
Detailed treatment data of 1905 veal calves from 38 farms were collected prospectively during monthly farm visits for 1 year (n = 1864 treatments, n = 535 visits); 1582 Escherichia coli, 1059 Pasteurella multocida and 315 Mannheimia haemolytica were isolated from rectal and nasopharyngeal swabs collected before slaughter and subjected to antimicrobial susceptibility testing by microdilution. Associations of antimicrobial treatments with resistant isolates were investigated at the calf level.
RESULTS
Associations of AMU with antimicrobial resistance were observed using generalized linear models. For E. coli, the odds of being resistant were increased with increased AMU (OR 1.36 when number of treatments >1, P = 0.066). Use of tetracyclines was associated with resistance to tetracycline (OR 1.86, P < 0.001) and use of penicillins was associated with resistance to ampicillin (OR 1.66, P = 0.014). No significant associations were observed for P. multocida (use of aminoglycosides: OR 3.66 for resistance to spectinomycin, P = 0.074). For M. haemolytica, the odds of being resistant were increased with increased AMU (OR 4.63, P < 0.001), and use of tetracyclines was associated with resistance to tetracycline (OR 6.49, P < 0.001).
CONCLUSIONS
Occurrence of resistant bacteria shortly before slaughter was associated with AMU in veal calves. Prudent and appropriate use may contribute to limit the selection of resistant bacteria on veal farms.
Topics: Ampicillin; Animals; Anti-Bacterial Agents; Anti-Infective Agents; Cattle; Cattle Diseases; Drug Resistance, Bacterial; Escherichia coli; Gastrointestinal Tract; Pasteurella multocida; Penicillins; Red Meat; Spectinomycin; Tetracycline
PubMed: 35962594
DOI: 10.1093/jac/dkac246 -
Journal of Animal Science Nov 2022Experimental bovine respiratory syncytial virus (BRSV) infection can enhance Histophilus somni (Hs) disease in calves; we thus hypothesized that modified-live virus...
Experimental bovine respiratory syncytial virus (BRSV) infection can enhance Histophilus somni (Hs) disease in calves; we thus hypothesized that modified-live virus (MLV) vaccines containing BRSV may alter Hs carriage. Our objective was to determine the effects of an intranasal (IN) trivalent (infectious bovine rhinotracheitis virus [IBRV], parainfluenza-3 virus [PI3V], and BRSV) respiratory vaccine with parenteral (PT) bivalent bovine viral diarrhea virus (BVDV) type I + II vaccine, or a PT pentavalent (BVDV type I and II, IBRV, BRSV, and PI3V) respiratory vaccine, on health, growth, immunity, and nasal pathogen colonization in high-risk beef calves. Calves (n = 525) were received in five truckload blocks and stratified by body weight (213 ± 18.4 kg), sex, and presence of a pre-existing ear-tag. Pens were spatially arranged in sets of three within a block and randomly assigned to treatment with an empty pen between treatment groups consisting of: 1) no MLV respiratory vaccination (CON), 2) IN trivalent MLV respiratory vaccine with PT BVDV type I + II vaccine (INT), or 3) PT pentavalent, MLV respiratory vaccine (INJ). The pen was the experimental unit, with 15 pens/treatment and 11 to 12 calves/pen in this 70-d receiving study. Health, performance, and BRSV, Hs, Mycoplasma bovis (Mb), Mannheimia haemolytica (Mh), and Pasteurella multocida (Pm) level in nasal swabs via rtPCR was determined on days 0, 7, 14, and 28, and BRSV-specific serum neutralizing antibody titer, and serum IFN-γ concentration via ELISA, were evaluated on days 0, 14, 28, 42, 56, and 70. Morbidity (P = 0.83), mortality (P = 0.68) and average daily gain (P ≥ 0.82) did not differ. Serum antibodies against BRSV increased with time (P < 0.01). There was a treatment × time interaction (P < 0.01) for Hs detection; on days 14 and 28, INT (21.1% and 57.1%) were more frequently (P < 0.01) Hs positive than CON (3.6% and 25.3%) or INJ (3.4 % and 8.4%). Also, INT had reduced (P = 0.03) cycle time of Hs positive samples on day 28. No difference (P ≥ 0.17) was found for IFN-γ concentration and Mb, Mh, or Pm detection. The proportion of Mh positive culture from lung specimens differed (P < 0.01); INT had fewer (0.0%; 0 of 9) Mh positive lungs than INJ (45.5%; 6 of 13) or CON (74.0%; 14 of 19). Vaccination of high-risk calves with MLV did not clearly impact health or growth during the receiving period. However, INT was associated with an altered upper respiratory microbial community in cattle resulting in increased detection and level of Hs.
Topics: Cattle; Animals; Viral Vaccines; Antibodies, Viral; Respiratory Syncytial Virus, Bovine; Vaccines, Attenuated; Herpesvirus 1, Bovine; Diarrhea Viruses, Bovine Viral; Mannheimia haemolytica; Cattle Diseases; Pasteurella multocida
PubMed: 35926833
DOI: 10.1093/jas/skac249 -
The Canadian Veterinary Journal = La... Aug 2022Bacterial bronchopneumonia occurs in mature dairy cows but much of the information is extrapolated from knowledge of the disease in calves. The study was prompted by...
OBJECTIVE
Bacterial bronchopneumonia occurs in mature dairy cows but much of the information is extrapolated from knowledge of the disease in calves. The study was prompted by perceptions of an increasing occurrence and a paucity of information on fatal pneumonia in dairy cows in Ontario. The study objectives were to describe the seasonality, main pathogens involved, and suggested predisposing factors for cases of fatal bacterial bronchopneumonia in mature dairy cows submitted for postmortem examination to a diagnostic laboratory, and to evaluate if the frequency of such submissions has increased over time.
ANIMALS
Mature dairy cows.
PROCEDURE
Retrospective study of cases submitted for postmortem examination to a diagnostic laboratory from 2007-2020 that were diagnosed as bacterial bronchopneumonia.
RESULTS
Most of the postmortem cases of bacterial bronchopneumonia in dairy cows were submitted from November to February (54% of cases). was isolated from lung of 61/101 cases. Viruses were only identified in 8/55 cases tested. A minority (29/92) of bacterial isolates had resistance to antimicrobials used to treat pneumonia. Frequently suggested predisposing factors included recent introductions or movement of animals, recent or imminent calving, inclement weather, concurrent diseases, and poor ventilation in barns.
CONCLUSION AND CLINICAL RELEVANCE
This study describes seasonal and annual trends, major pathogens, antimicrobial resistance profiles, and suggested predisposing factors in Ontario dairy cows submitted to a diagnostic laboratory for postmortem investigation of pneumonia and provides insights for understanding why outbreaks occur.
Topics: Animals; Bacteria; Bronchopneumonia; Cattle; Cattle Diseases; Female; Mannheimia haemolytica; Pneumonia, Bacterial; Retrospective Studies
PubMed: 35919462
DOI: No ID Found -
American Journal of Veterinary Research Jul 2022To investigate the clinical value of selected biomarkers for evaluation of systemic inflammatory response and pulmonary inflammation and damage pattern in calves with...
OBJECTIVE
To investigate the clinical value of selected biomarkers for evaluation of systemic inflammatory response and pulmonary inflammation and damage pattern in calves with different pneumonia forms.
ANIMALS
16 calves with fibrinous pneumonia (FP group; infected with Mannheimia haemolytica or Pasteurella multocida), 12 calves with caseonecrotic pneumonia (CNP group; infected with Mycoplasma bovis), and 10 healthy calves (C group) based on results of bronchoalveolar lavage fluid (BALF) examination.
PROCEDURES
Blood and BALF samples were collected. Annexin-A2 (Anx-A2), endothelin-1 (ET-1), calgranulin B (S100A9), transforming growth factor-β1 (TGF-β1), tumor necrosis factor-α (TNF-α), interleukin-17A (IL-17A), haptoglobin (Hp), lipopolysaccharide-binding protein (LBP), and albumin (Alb) concentrations and lactate dehydrogenase (LDH) and alkaline phosphatase (ALP) activities were measured and compared across groups.
RESULTS
Serum concentrations of Anx-A2, S100A9, TGF-β1, TNF-α, IL-17A, Hp, and LBP and activities of LDH and ALP were higher and Alb concentrations were lower for the pneumonia groups versus C group. BALF concentration ratios of S100A9:Alb, LBP:Alb, LDH:Alb, and ALP:Alb were higher for the pneumonia groups versus C group (P < .05). BALF concentration ratios of Anx-A2:Alb, TGF-β1:Alb, and IL-17A:Alb were higher for the FP group versus other groups (P < .05).
CLINICAL RELEVANCE
Results indicated that serum Anx-A2, S100A9, TGF-β1, TNF-α, IL-17A, Hp, LBP, and Alb concentrations were useful in determining the systemic inflammatory response and that BALF concentration ratios of S100A9:Alb, TGF-β1:Alb, LBP:Alb, and ALP:Alb were useful biomarkers in determining pulmonary inflammation and damage. Measurements of BALF concentration ratios of Anx-A2:Alb, TGF-β1:Alb, and IL-17A:Alb could be beneficial to defining fibrinous characterization of pulmonary inflammation.
Topics: Animals; Biomarkers; Bronchoalveolar Lavage Fluid; Cattle; Cattle Diseases; Interleukin-17; L-Lactate Dehydrogenase; Pneumonia; Systemic Inflammatory Response Syndrome; Transforming Growth Factor beta1; Tumor Necrosis Factor-alpha
PubMed: 35895787
DOI: 10.2460/ajvr.21.10.0172