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Veterinary World Jul 2019Mannheimiosis or pneumonic pasteurellosis commonly occurs in small ruminants. Mannheimiosis is caused by () a Gram-negative coccobacillus producing acute febrile and... (Review)
Review
Mannheimiosis or pneumonic pasteurellosis commonly occurs in small ruminants. Mannheimiosis is caused by () a Gram-negative coccobacillus producing acute febrile and infectious condition resulting in death of animal if not diagnosed and treated promptly. serotype A2 is a commensal of the nasopharynx, gaining access to the lungs when host defenses are compromised by stress or infection in small ruminants. Till date, there is a vast literature and research that has been conducted on the pathogenesis of invariably on respiratory system and its related immune system and mechanisms. From the clinical point of view, infection or diseases involving vital organs will systemically affect the production and performance of the infected animal. Therefore, there is a huge gap of knowledge and research to answer the question whether there is any association between infection with reproductive physiology and performance in small ruminants and how it affects the productivity level. This review will explore the possibilities of involvement and new potential research to be carried out to determine the involvement of male and female reproductive system with infection among small ruminants.
PubMed: 31528021
DOI: 10.14202/vetworld.2019.978-983 -
Veterinary Microbiology Jan 2024Mannheimia haemolytica is known as one of the major bacterial contributors to Bovine Respiratory Disease (BRD) syndrome. This study sought to establish a novel...
Mannheimia haemolytica is known as one of the major bacterial contributors to Bovine Respiratory Disease (BRD) syndrome. This study sought to establish a novel species-specific PCR to aid in identification of this key pathogen. As well, an existing multiplex PCR was used to determine the prevalence of serovars 1, 2 or 6 in Australia. Most of the 65 studied isolates originated from cattle with a total of 11 isolates from small ruminants. All problematic field isolates in the identification or serotyping PCRs were subjected to whole genome sequencing and bioinformatic analysis. The field isolates were also subjected to rep-PCR fingerprinting. A total of 59 out of the 65 tested isolates were conformed as M. haemolytica by the new species-specific PCR which is based on the rpoB gene. The confirmed M. haemolytica field isolates were assigned to serovars 1 (24 isolates), 2 (seven isolates) and 6 (26 isolates) while two of the isolates were negative in the serotyping PCR. The two non-typeable isolates were assigned to serovar 7 and 14 following whole genome sequencing and bioinformatic analysis. The rep-PCR typing resulted in five major clusters with serovars 1 and 6 often within the same cluster. The M. haemolytica-specific PCR developed in this work was species specific and should be a valuable support for frontline diagnostic laboratories. The serotyping results support the relative importance of serovars 1 and 6 in bovine respiratory disease.
Topics: Cattle; Animals; Mannheimia haemolytica; Bacteria; Serotyping; Cattle Diseases; Ruminants; Multiplex Polymerase Chain Reaction; Respiratory Tract Diseases
PubMed: 38086163
DOI: 10.1016/j.vetmic.2023.109930 -
Veterinary Pathology Mar 2024-associated abomasitis has been clinically described as a cause of sudden death in lambs, but it is poorly characterized. We describe the pathological features of a...
-associated abomasitis has been clinically described as a cause of sudden death in lambs, but it is poorly characterized. We describe the pathological features of a severe fibrinonecrotizing abomasitis in 3 lambs that died suddenly. All 3 abomasums had a thickened submucosa due to edema and necrotic areas delimited by bands of degenerate neutrophils with slender nuclei (oat cells) and angiocentric distributions. The overlying mucosa was congested. Myriads of gram-negative coccobacilli were observed within the oat cell bands. was isolated from the abomasum in all 3 animals and was serotyped as A2 in one of them. Pericarditis and pleuritis were observed in 2 of the lambs. spp. were isolated in 1 lamb and detected by immunohistochemistry in the 3 animals, suggesting clostridial co-infection. should be considered among the differential diagnoses of necrotizing abomasitis in lambs.
PubMed: 38440930
DOI: 10.1177/03009858241235393 -
Animals : An Open Access Journal From... Jun 2023is the main pathogen contributing to pneumonic pasteurellosis in sheep. The aim of this study was to investigate the antimicrobial resistance levels in isolates from...
is the main pathogen contributing to pneumonic pasteurellosis in sheep. The aim of this study was to investigate the antimicrobial resistance levels in isolates from the lungs of slaughtered sheep and to examine the genetic resistance mechanisms involved. A total of 256 isolates, 169 from lungs with pneumonic lesions and 87 from lungs without lesions, were analyzed by the disk diffusion method for 12 antimicrobials, and the whole genome of 14 isolates was sequenced to identify antimicrobial resistance determinants. Levels of phenotypic resistance ranged from <2% for 10 antimicrobials (amoxicillin, amoxicillin-clavulanic, ceftiofur, cefquinome, lincomycin/spectinomycin, gentamicin, erythromycin, florfenicol, enrofloxacin, and doxycycline) to 4.3% for tetracycline and 89.1% for tylosin. Six isolates carried genes and four isolates carried, in addition, the and genes in putative plasmid sequences. No mutations associated with macrolide resistance were identified in 23 rDNA sequences, suggesting that the phenotypic results for tylosin should be interpreted with care in the absence of well-established epidemiological and clinical breakpoints. The identification of strains phenotypically resistant to tetracycline and of several resistance genes, some of which were present in plasmids, highlights the need for continuous monitoring of susceptibility patterns in isolates from livestock.
PubMed: 37370501
DOI: 10.3390/ani13121991 -
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 -
Pathogens (Basel, Switzerland) Aug 2019The objective of this review is to describe the usage and applicability of proteomics technologies in the study of mastitis in ewes. In ewes, proteomics technologies... (Review)
Review
The objective of this review is to describe the usage and applicability of proteomics technologies in the study of mastitis in ewes. In ewes, proteomics technologies have been employed for furthering knowledge in mastitis caused by various agents (, , , , ). Studies have focused on improving knowledge regarding pathogenesis of the infections and identifying biomarkers for its diagnosis. Findings have revealed that ewes with mastitis mount a defence response, controlled by many proteins and over various mechanisms and pathways, which are interdependent at various points. Many proteins can participate in this process. Moreover, as the result of proteomics studies, cathelicidins and serum amyloid A have been identified as proteins that can be used as biomarkers for improved diagnosis of the disease. In the long term, proteomics will contribute to improvements in the elucidation of the pathogenesis of mastitis. Further in-depth investigations into the various proteomes and application of new methodological strategies in experimental and clinical studies will provide information about mastitis processes, which will be of benefit in controlling the disease. Improvement of diagnostic techniques, establishment of prognostic tools and development of vaccines are key areas for targeted research.
PubMed: 31470519
DOI: 10.3390/pathogens8030134 -
Scientific Reports Jan 2021Bovine respiratory disease (BRD) linked with Mannheimia haemolytica is the principal cause of pneumonia in cattle. Diagnosis of BRD traditionally relies on visual...
Bovine respiratory disease (BRD) linked with Mannheimia haemolytica is the principal cause of pneumonia in cattle. Diagnosis of BRD traditionally relies on visual assessment, which can be untimely, insensitive, and nonspecific leading to inadequate treatment and further spread of disease. Near Infrared Spectroscopy (NIRS) is a rapid acquisition vibrational spectroscopy that can profile changes in biofluids, and when used in combination with multivariate analysis, has potential for disease diagnosis. This study characterizes the NIR spectral profile of blood plasma from dairy calves infected with M. haemolytica and validates the spectral biochemistry using standardized clinical and hematological reference parameters. Blood samples were collected for four days prior to (baseline), and 23 days after, a controlled intrabronchial challenge. NIR spectral profiles of blood plasma discriminated and predicted Baseline and Infected states of animal disease progression with accuracy, sensitivity, and specificity ≥ 90% using PCA-LDA models. These results show that physiological and biochemical changes occurring in the bloodstream of dairy calves during M. haemolytica infection are reflected in the NIR spectral profiles, demonstrating the potential of NIRS as a diagnostic and monitoring tool of BRD over time.
Topics: Animals; Cattle; Female; Mannheimia haemolytica; Pasteurellaceae Infections; Pneumonia of Calves, Enzootic; Spectroscopy, Near-Infrared
PubMed: 33446786
DOI: 10.1038/s41598-021-81032-x -
BMC Veterinary Research Jan 2022Mannheimia haemolytica is commonly associated with respiratory disease in cattle worldwide as a cause of fibrinous pneumonia, bronchopneumonia and pleuritis. M....
BACKGROUND
Mannheimia haemolytica is commonly associated with respiratory disease in cattle worldwide as a cause of fibrinous pneumonia, bronchopneumonia and pleuritis. M. haemolytica is further subdivided into 12 serovars, however not all are considered to be pathogenic in cattle. The study aim was to determine the most common serovars of M. haemolytica associated with respiratory disease in cattle in Great Britain, which is currently unknown and could be useful information for clinicians when considering preventative strategies.
RESULTS
One hundred four M. haemolytica isolates isolated from bovine clinical pathology and post-mortem samples from pneumonia cases between 2016 and 2018 were tested using a multiplex PCR assay to identify M. haemolytica serovars A1, A2 and A6. 46 isolates (44.2%) typed as M. haemolytica serovar A1, 31 (29.8%) as M. haemolytica serovar A2 and 18 isolates (17.3%) as M. haemolytica serovar A6. Nine isolates (8.7%) were not A1, A2 or A6 so were considered to belong to other serovars or were not typable.
CONCLUSION
This study highlights the importance of M. haemolytica serovars other than A1 which may be responsible for respiratory disease in cattle and could help guide the veterinarian when making choices on preventative vaccination programmes.
Topics: Animals; Bronchopneumonia; Cattle; Cattle Diseases; Mannheimia haemolytica; Pleurisy; Serogroup; United Kingdom
PubMed: 34980139
DOI: 10.1186/s12917-021-03121-3 -
Veterinary Journal (London, England :... Feb 2023Fatal Mannheimia haemolytica (M. haemolytica) infections in cattle, which emerged in the Netherlands between 2004 and 2018, showed two distinct disease presentations:...
Fatal Mannheimia haemolytica (M. haemolytica) infections in cattle, which emerged in the Netherlands between 2004 and 2018, showed two distinct disease presentations: acute fibrinous polyserositis (FPS) in veal calves, and acute fibrinous pleuro-pneumonia (FPP) in adult dairy cattle. To determine whether these presentations were caused by different M. haemolytica genotypes, whole genome sequencing was performed on 96 isolates cultured after necropsy from inflamed sites of veal calves that died of M. haemolytica-associated FPS (n = 49) or with FPP lesions (n = 2), and from dairy cows that died of M. haemolytica-associated FPP (n = 45). Among the 96 M. haemolytica isolates, 93 were shown to belong to either of two large clusters, with 48/51 calf isolates belonging to one, and 43/45 cow isolates and two calf isolates from cases of FPP to the other. All M. haemolytica isolates from veal calves with FPS were of serotype A2, whereas the isolates from dairy cows and two calves with FPP were predominantly of serotypes A1 and A6. Most serotype A2 isolates from veal calves with FPS (95.6 %) contained multiple antibiotic resistance genes (ARGs) against three to five antimicrobial classes (phenicols, sulphonamides, tetracyclines, aminoglycosides or beta-lactams). In contrast, these ARGs were only present in 10.8 % of M. haemolytica A1 and A6 isolates from pneumonic adult cattle and absent in isolates from the two calves with FPP. These two disease presentations appear to be caused by genetically distinct strains with different antimicrobial resistance gene patterns. While M. haemolytica serotype A2 is generally considered to be a commensal microorganism of cattle, it was clearly associated with fatal FPS in veal calves in the Netherlands.
PubMed: 36543311
DOI: 10.1016/j.tvjl.2022.105940 -
BMC Research Notes Jan 2023Mannheimia haemolytica is the primary bacterial pathogen associated with bovine respiratory disease complex (BRDC). While M. haemolytica has been subdivided into 12...
OBJECTIVE
Mannheimia haemolytica is the primary bacterial pathogen associated with bovine respiratory disease complex (BRDC). While M. haemolytica has been subdivided into 12 capsular serotypes (ST), ST1, ST2 and ST6 are commonly isolated from cattle. More recently, M. haemolytica strains isolated from North American cattle have been classified into genotypes 1 (ST2) and 2 (ST1 and ST6). Of the two genotypes, genotype 1 strains are frequently isolated from healthy animals whereas, genotype 2 strains are predominantly isolated from BRDC animals. However, isolation of both genotypes from pneumonic lung samples can complicate diagnosis. Therefore, the aim of this study was to develop a colorimetric loop-mediated isothermal amplification (LAMP) assay to differentiate M. haemolytica genotypes.
RESULTS
The genotype specificity of the LAMP was tested using purified genomic DNA from 22 M. haemolytica strains (10 genotype 1, 12 genotype 2) and strains from four related Pasteurellaceae species; Bibersteinia trehalosi, Mannheimia glucosida, Pasteurella multocida, and Histophilus somni. Genotype 1 (adhesin pseudogene B1) specific-LAMP reactions amplified DNA only from genotype 1 strains while genotype 2 (adhesin G) reactions amplified DNA only from genotype 2 strains. The overall detection sensitivity and specificity of the newly developed colorimetric LAMP assay for each genotype were 100%. The limits of detection of two LAMP assays were 1-100 target gene copies per reaction. LAMP primers designed in this study may help the differential identification of M. haemolytica genotypes 1 and 2.
Topics: Cattle; Animals; Mannheimia haemolytica; Colorimetry; Interleukin-1 Receptor-Like 1 Protein; Genotype
PubMed: 36658613
DOI: 10.1186/s13104-023-06272-8