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Saponin-based Mycoplasma bovis vaccine containing lysozyme dimer adjuvant stimulates acute phase response in calves
2018
Dudek, Katarzyna | Bednarek, Dariusz
Mycoplasma bovis is known as a causative agent of many disorders in cattle. In Europe, there is still a lack of commercial vaccines against M. bovis infection. Acute phase response (APR) is a non-specific host reaction to infection, most seen in changes in production of acute phase proteins. The aim of this study was to analyse APR in calves administered with an experimental M. bovis vaccine. Twelve healthy female calves were divided into two equal groups: experimental and control. The experimental vaccine containing the field M. bovis strain and two adjuvants such as saponin and lysozyme dimer was subcutaneously administered to the experimental group. Phosphate buffered saline was taken as the placebo and given to the control group by the same route as the vaccine. Blood samples were collected prior to the study (day 0), then daily up to day 7, and then each seven days until day 84 post vaccination. The concentrations of serum amyloid A (SAA), haptoglobin (Hp), interferon-γ (IFN-γ), and inteleukin-4 (IL-4) were determined using commercial ELISA kits. Following the vaccination, a significant increase in SAA, Hp, and IFN-γ concentrations was observed when compared to the unvaccinated calves, whereas the IL-4 concentration was not detectable. The experimental saponin-based M. bovis vaccine containing lysozyme dimer adjuvant visibly stimulated the APR in the calves, and some specific cytokines (Th1-dependent) directly involved in this response.
Show more [+] Less [-]Prevalence of pathogens from Mollicutes class in cattle affected by respiratory diseases and molecular characteristics of Mycoplasma bovis field strains
2016
Szacawa, Ewelina | Szymańska-Czerwińska, Monika | Niemczuk, Krzysztof | Dudek, Katarzyna | Woźniakowski, Grzegorz | Bednarek, Dariusz
Introduction: Mycoplasma bovis is one of the main pathogens involved in cattle pneumonia. Other mycoplasmas have also been directly implicated in respiratory diseases in cattle. The prevalence of different Mycoplasma spp. in cattle affected by respiratory diseases and molecular characteristics of M. bovis field strains were evaluated. Material and Methods: In total, 713 nasal swabs from 73 cattle herds were tested. The uvrC gene fragment was amplified by PCR and PCR products were sequenced. PCR/DGGE and RAPD were performed. Results: It was found that 39 (5.5%) samples were positive for M. bovis in the PCR and six field strains had point nucleotide mutations. Additionally, the phylogenetic analysis of 20 M. bovis field strains tested with RAPD showed two distinct groups of M. bovis strains sharing only 3.8% similarity. PCR/DGGE analysis demonstrated the presence of bacteria belonging to the Mollicutes class in 79.1% of DNA isolates. The isolates were identified as: Mycoplasma bovirhinis, M. dispar, M. bovis, M. canis, M. arginini, M. canadense, M. bovoculi, M. alkalescens, and Ureaplasma diversum. Conclusion: Different Mycoplasma spp. strains play a crucial role in inducing respiratory diseases in cattle.
Show more [+] Less [-]Screening of the Cervidae family in Poland for Mycoplasma species
2016
Dudek, Katarzyna | Bednarek, Dariusz | Szacawa, Ewelina | Ayling, Roger D.
Introduction: Several Mycoplasma species can cause severe diseases in ruminant hosts, some of which are the diseases listed by the World Organisation for Animal Health (OIE). The role of the Cervidae family in carrying and transmitting ruminant mycoplasma infections in Poland is unknown. Material and Methods: Antibody and antigen detection tests for the main mycoplasma species that can affect wild ruminants were performed on 237 samples (serum, nasal swab, bronchoalveolar lavage, and lung) collected from 161 animals during 2011-2014. The samples were obtained from a cull of healthy population of deer which included: 96 red deer (Cervus elaphus elaphus), 19 fallow deer (Dama dama), and 46 roe deer (Capreolus capreolus). Results: Serological screening tests revealed positive reactions to Mycoplasma bovis in one sample and to Mycoplasma capricolum subsp. capripneumoniae in three samples; however, these three samples were negative by immunoblotting. Other antibody and antigen detection tests demonstrated negative results. Conclusion: Currently wild cervids in Poland do not play a significant role in transmitting mycoplasma infections to domestic animals, but they remain a potential risk.
Show more [+] Less [-]ELISA-based serological survey of Mycoplasma bovis in cattle in three local government areas in Adamawa State, Nigeria
2015
Markus Isa Francis | Mashood Abiola Raji | Haruna Makanjuola Kazeem | Mohammed Musa Suleiman
A serological survey for the detection of antibodies to Mycoplasma bovis was conducted in Adamawa State, Nigeria during the year 2012. A total of 400 serum samples were collected from three local government areas (LGA) namely Yola (n=140), Mubi (n=130) and Ganye (n=130), and the samples were examined for the presence of M. bovis antibodies using BIO-X M. bovis antibody ELISA Kit. The overall seroprevalence of M. bovis was recorded as 19.5% (n=78/400). The highest seroprevalence was recorded in Ganye LGA (27.7%; n=36/130), followed by Yola LGA (20.0%; n=28/140) and Mubi LGA (10.8%; n=14/130). The cattle aging <1-year had the highest prevalence (25.8%), followed by 4-year-old cattle (22.4%). Based on sex distribution, 20.4% of the cows and 17.4% of the bulls were seropositive to M. bovis. Breed susceptibility to M. bovis infection showed that White Fulani had the highest prevalence (21.8%), and Sokoto Gudali had the lowest (11.9%). No statistical significant association was found between M. bovis infection and age, sex and breed of the cattle. In conclusion, the above findings are indicative for the presence of M. bovis in the study area.
Show more [+] Less [-]Prevalence and genotype of Mycoplasma bovis in beef cattle after arrival at a feedlot
2012
Castillo-Alcala, Fernanda | Bateman, Kenneth G. | Cai, Hugh Y. | Schott, Courtney R. | Parker, Lois | Clark, Mary Ellen | McRaild, Patricia | McDowall, Rebecca M. | Foster, Robert A. | Archambault, Marie | Caswell, Jeff L.
Objective: To determine the prevalence of Mycoplasma bovis infection in the lungs of cattle at various times after arrival at a feedlot, to measure the relationship between clinical disease status and the concentration and genotype of M bovis within the lungs, and to investigate changes in the genotype of M bovis over time. Sample: Bronchoalveolar lavage fluid (BALF) from 328 healthy or pneumonic beef cattle and 20 M bovis isolates obtained from postmortem samples. Procedures: The concentration of M bovis in BALF was determined via real-time PCR assays, and M bovis isolates from BALF were genotyped via amplified fragment length polymorphism (AFLP) analysis. Results: Prevalence of M bovis in BALF was 1 of 60 (1.7%) at arrival to a feedlot and 26 of 36 (72.2%) and 36 of 42 (85.7%) at ≤ 15 days and 55 days after arrival, respectively. Neither the concentration nor the AFLP type of M bovis in BALF was correlated with clinical disease status. The M bovis AFLP type differed between early and later sampling periods in 14 of 17 cattle. Conclusions and Clinical Relevance: The findings implied spread of M bovis among calves and suggested that host factors and copathogens may determine disease outcomes in infected calves. Chronic pulmonary infection with M bovis may represent a dynamic situation of bacterial clearance and reinfection with strains of different AFLP type, rather than continuous infection with a single clone. These findings impact our understanding of why cattle with chronic pneumonia and polyarthritis syndrome inadequately respond to antimicrobial treatment.
Show more [+] Less [-]Changes in antimicrobial susceptibility profiles of Mycoplasma bovis over time
2019
Cai, H. Y. | McDowall, R. | Parker, L. | Kaufman, E. l | Caswell, J. C.
Mycoplasma bovis is a major cause of pneumonia, arthritis, and mastitis in cattle and can lead to significant economic losses. Antimicrobial resistance is a concern and further limits the already short list of drugs effective against mycoplasmas. The objective of this study was to examine changes in in vitro minimum inhibitory concentrations (MICs) of antimicrobials of aminoglycoside, fluoroquinolone, lincosamide, macrolide, pleuromutilin, phenicol, and tetracycline classes for 210 M. bovis isolates collected from 1978 to 2009. The MIC(50) values of the various antimicrobials were also compared. The MIC(50) levels for enrofloxacin and danofloxacin remained low (0.25 μg/mL) across all 3 decades. MIC(50) levels for tetracyclines, tilmicosin, and tylosin tartrate were low in the 1980s, then increased in the 1990s and remained high. In the 1980s, MIC(50) levels were low for clindamycin, spectinomycin, and tulathromycin, increased in the 1990s to 8 μg/mL (clindamycin) and 32 μg/mL (spectinomycin and tulathromycin), then decreased again in the 2000s. Members of the fluoroquinolone class of antimicrobials had the lowest MIC(50) levels across all 3 decades, which suggests in vitro susceptibility of M. bovis to this class of antimicrobials. Statistically significant associations were observed between MIC values for chlortetracycline, oxytetracycline, tylosin tartrate, and tilmicosin; between clindamycin, tulathromycin, spectinomycin, and tiamulin; and between tylosin tartrate and clindamycin. Changes in MIC levels of various antimicrobials over time show the importance of monitoring the susceptibility of mycoplasmas to antimicrobials. The number of antimicrobials that showed elevated MIC(50) levels, and therefore possibly reduced in vitro effectiveness against M. bovis, supports initiatives that promote prudent use of antimicrobials in agriculture.
Show more [+] Less [-]Precision and accuracy of clinical illness scores, compared with pulmonary consolidation scores, in Holstein calves with experimentally induced Mycoplasma bovis pneumonia
2013
Amrine, David E. | White, Brad J. | Larson, Robert | Anderson, David E. | Mosier, Derek A. | Cernicchiaro, Natalia
Objective: To determine the precision of a clinical illness score (CIS) system for identification of clinical signs in calves with experimentally induced Mycoplasma bovis pneumonia and to evaluate the accuracy of CISs in relation to pulmonary consolidation scores assigned at necropsy. Animals: 178 Holstein bull calves that were 52 to 91 days of age at the time of pneumonia induction. Procedures: 5 trials involved calves challenged with M bovis and scheduled for euthanasia and necropsy 12 to 24 days afterward. Nine veterinarian observers with various degrees of experience simultaneously assigned CISs to calves within 48 hours before necropsy. The precision of the CIS system among observers was evaluated via the Cohen κ statistic. The accuracy of each observer's CISs relative to 6 cutoffs (≥ 5%, ≥ 10%, ≥ 15%, ≥ 20%, ≥ 25%, and ≥ 30%) of percentage pulmonary consolidation was determined by comparing prenecropsy CISs with the gross pulmonary consolidation scores assigned at necropsy. Estimates for sensitivity and specificity were calculated relative to the 6 pulmonary consolidation cutoffs. Results: A slight level of agreement was evident among observers (κ range, 0.10 to 0.21 for the individual trials) and overall (κ = 0.16; 95% confidence interval, 0.10 to 0.24). Median sensitivity and specificity changed with pulmonary consolidation score cutoff. Median sensitivity for all observers ranged from 81.7% to 98.9%, and median specificity ranged from 80.8% to 94.9% over all cutoff values. Conclusions and Clinical Relevance: Agreement among observers assigning CISs to calves was low; the accuracy of the CIS system in relation to that of pulmonary consolidation scoring varied with the severity of consolidation considered to represent bovine respiratory disease.
Show more [+] Less [-]Rapid identification of bacterial pathogens related with bovine respiratory diseases by using PCR
Jung, B.Y.(National Veterinary Research and Quarantine Service, Anyang, Republic of Korea)E-mail:jungby@nvrqs.go.kr
Haemophilus somnus, Mycoplasma bovis and Pasteurella multocida were responsible for respiratory diseases in bovine. Methods for identifying these bacteria had poor sensitivity and specificity. In this paper, PCR assays were applied for rapid identification of H. somnus, M. bovis, P. multocida B:2 and P. multocida capsular types. The specific PCR products were amplified from H. somnus, but not from other bacteria. Ten-fold diluted H. somnus were mixed with P. multocida and then the mixed cultures were inoculated on agar plates.
Show more [+] Less [-]Associations of various physical and blood analysis variables with experimentally induced Mycoplasma bovis pneumonia in calves
2014
Fraser, Brandon C. | Anderson, David E. | White, Brad J. | Miesner, Matt D. | Lakritz, Jeff | Amrine, David | Mosier, Derek A.
Objective-To determine associations of blood analysis variables and orbit and nasal planum surface temperatures with the onset and severity of Mycoplasma bovis pneumonia in calves. Animals-28 healthy calves. Procedures-Calves were challenged with M bovis (n = 24) on day 0 or not challenged (4). Blood samples were obtained for cardiac troponin I, CBC, and serum biochemical analyses on various days. Orbit and nasal planum surface temperatures were determined with infrared thermography on various days. Calves were euthanized, gross necropsies were performed, heart and lung samples were collected for histologic evaluation, and microbial cultures of lung samples were performed on day 14. Pneumonia severity was categorized as mild (< 10% lung consolidation) or moderate (≥ 10% lung consolidation). Associations between measured variables and severity of pneumonia or sample collection day were determined. Results-Plasma cardiac troponin I concentration for the 28 calves was significantly higher on day 14 than it was on day 0 or 7 (least squares mean, 0.02, 0, and 0 ng/mL, respectively). No other variables changed significantly during the study. No substantial gross or histologic abnormalities were identified in cardiac muscle samples. Day 14 plasma fibrinogen concentration was significantly different between calves with mild pneumonia and those with moderate pneumonia (mean, 0.44 and 0.74 g/dL, respectively). Calves with moderate pneumonia had significantly lower least squares mean surface temperature of the dorsal aspect of the nasal planum (18.7°C) versus calves with mild pneumonia (22.9°C). Conclusions and Clinical Relevance-Results indicated the evaluated variables had low value for assessment of bovine respiratory disease complex in calves.
Show more [+] Less [-]Clinical, behavioral, and pulmonary changes in calves following inoculation with Mycoplasma bovis
2012
White, Brad J. | Anderson, David E. | Renter, David G. | Larson, Robert L. | Mosier, Derek A. | Kelly, Lindsey L. | Theurer, Miles E. | Robert, Brad D. | Walz, Michelle L.
Objective: To characterize clinical and behavioral changes in calves following inoculation with Mycoplasma bovis and evaluate relationships between those changes and pulmonary disease. Animals: 22 healthy Holstein steers. Procedures: 20 calves were inoculated intranasally with < 10(8) CFU or > 10(9) CFU of M bovis. Calves were assigned a clinical illness score (CIS) on a scale of 1 through 4 twice daily on the basis of severity of cough, labored breathing, and lethargy. For each calf, distance traveled and time spent near the waterer, feed bunk, or shelter were determined via a remote location monitoring device. Calves were euthanized and necropsied 22 days after inoculation. Results: 13 calves became clinically ill after challenge inoculation; 3 calves were euthanized within 20 days. Among all calves, consolidation was evident in 0% to 79.9% of the lungs; extent of lung consolidation did not differ between the challenge dose groups. Distance traveled and percentages of time spent in proximity to the feed bunk and shelter were associated with CIS; calves with more severe disease traveled less distance and spent less time at the feed bunk and more time in the shelter. Distance traveled by calves was negatively associated with extent of lung consolidation (< or ≥ 10% of lungs affected); this effect was modified by trial day. Conclusions and Clinical Relevance: Following inoculation with M bovis, calf behavior patterns were associated with both CIS and severity of pulmonary disease. Use of behavior monitoring systems may aid in recognition of respiratory tract disease in calves.
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