-
Vaccine Mar 2012Bovine respiratory disease causes significant economic losses in both beef and dairy calf industries. Although multi-factorial in nature, the disease is characterized by...
Cross protection of a Mannheimia haemolytica A1 Lkt-/Pasteurella multocida ΔhyaE bovine respiratory disease vaccine against experimental challenge with Mannheimia haemolytica A6 in calves.
Bovine respiratory disease causes significant economic losses in both beef and dairy calf industries. Although multi-factorial in nature, the disease is characterized by an acute fibrinous lobar pneumonia typically associated with the isolation of Mannheimia haemolytica. M. haemolytica A1 and A6 are the two most commonly isolated serotypes from cattle, however, the majority of vaccines have not demonstrated cross-serotype protection. In the current study, the efficacy of a novel, attenuated live vaccine, containing both M. haemolytica serotype A1 and Pasteurella multocida, was evaluated in calves challenged with M. haemolytica serotype A6. Although the challenge was more severe than expected, vaccinated calves had reduced clinical scores, lower mortality, and significantly lower lung lesion scores compared to the placebo-vaccinated control group. The results demonstrate that vaccination with an attenuated live vaccine containing M. haemolytica serotype A1 can protect calves against clinical disease following challenge with M. haemolytica serotype A6.
Topics: Animals; Bacterial Proteins; Bacterial Vaccines; Base Sequence; Cattle; Cattle Diseases; Cross Protection; Exotoxins; Mannheimia haemolytica; Molecular Sequence Data; Pasteurella multocida; Pasteurellosis, Pneumonic; Serotyping; Treatment Outcome; Vaccination; Vaccines, Attenuated
PubMed: 22306859
DOI: 10.1016/j.vaccine.2012.01.063 -
Applied and Environmental Microbiology Feb 2010Mannheimia (Pasteurella) haemolytica is the only pathogen that consistently causes severe bronchopneumonia and rapid death of bighorn sheep (BHS; Ovis canadensis) under...
Mannheimia (Pasteurella) haemolytica is the only pathogen that consistently causes severe bronchopneumonia and rapid death of bighorn sheep (BHS; Ovis canadensis) under experimental conditions. Paradoxically, Bibersteinia (Pasteurella) trehalosi and Pasteurella multocida have been isolated from BHS pneumonic lungs much more frequently than M. haemolytica. These observations suggest that there may be an interaction between these bacteria, and we hypothesized that B. trehalosi overgrows or otherwise inhibits the growth of M. haemolytica. Growth curves (monoculture) demonstrated that B. trehalosi has a shorter doubling time ( approximately 10 min versus approximately 27 min) and consistently achieves 3-log higher cell density (CFU/ml) compared to M. haemolytica. During coculture M. haemolytica growth was inhibited when B. trehalosi entered stationary phase (6 h) resulting in a final cell density for M. haemolytica that was 6 to 9 logs lower than expected with growth in the absence of B. trehalosi. Coculture supernatant failed to inhibit M. haemolytica growth on agar or in broth, indicating no obvious involvement of lytic phages, bacteriocins, or quorum-sensing systems. This observation was confirmed by limited growth inhibition of M. haemolytica when both pathogens were cultured in the same media but separated by a filter (0.4-microm pore size) that limited contact between the two bacterial populations. There was significant growth inhibition of M. haemolytica when the populations were separated by membranes with a pore size of 8 mum that allowed free contact. These observations demonstrate that B. trehalosi can both outgrow and inhibit M. haemolytica growth with the latter related to a proximity- or contact-dependent mechanism.
Topics: Animals; Bacteriological Techniques; Base Sequence; Colony Count, Microbial; DNA, Bacterial; Mannheimia haemolytica; Models, Biological; Pasteurella; Pasteurella multocida; Pasteurellaceae Infections; Pneumonia, Bacterial; Sheep; Sheep Diseases; Sheep, Bighorn
PubMed: 20038698
DOI: 10.1128/AEM.02086-09 -
The Onderstepoort Journal of Veterinary... Dec 2006An indirect enzyme-linked immunosorbent assay (ELISA) was developed for the quantification of extracellular leukotoxin (LKT) produced in chemostat culture of Mannheimia...
An indirect enzyme-linked immunosorbent assay (ELISA) was developed for the quantification of extracellular leukotoxin (LKT) produced in chemostat culture of Mannheimia haemolytica in a serum-free culture medium. Leukotoxin purified with preparative SDS-PAGE was used for the production of chicken polyclonal antibodies (PAb) that served as the primary detecting antibody. Excising the LKT protein from an analytical SDS-PAGE gel proved an efficient technique for the purification of the toxin. Consequently, the 102 kDa LKT polypeptide purified in this manner served as reference toxin and the resulting calibration curve was modelled using a four parameter logistic fit to relate absorbance to LKT protein concentration. The lower detection limit corresponded to an LKT concentration of 14.5 ng ml(-1). The presence of SDS, serum albumin and the coating pH had a distinct effect on the absorbance values of the indirect ELISA.
Topics: Animals; Antibodies, Monoclonal; Cattle; Chickens; Culture Media, Serum-Free; Cytotoxins; Electrophoresis, Polyacrylamide Gel; Enzyme-Linked Immunosorbent Assay; Exotoxins; Mannheimia haemolytica; Pasteurella Infections; Reference Values; Sensitivity and Specificity; Sheep
PubMed: 17283723
DOI: No ID Found -
Veterinary Microbiology Feb 2002Leukotoxins are a group of exotoxins that produce their primary toxic effects against leukocytes, especially polymorphonuclear cells (PMNs). Leukotoxins include a... (Review)
Review
Leukotoxins are a group of exotoxins that produce their primary toxic effects against leukocytes, especially polymorphonuclear cells (PMNs). Leukotoxins include a variety of chemicals ranging from 9,10-epoxy 12-octadecenoate, a fatty acid derivative secreted by leukocytes themselves, to proteins such as RTX (repeats in toxin). This review focuses on leukotoxins of three species of gram-negative bacteria, Mannheimia (Pasteurella) haemolytica, Actinobacillus actinomycetemcomitans, and Fusobacterium necrophorum.
Topics: Aggregatibacter actinomycetemcomitans; Bacterial Toxins; Exotoxins; Fusobacterium necrophorum; Gram-Negative Bacteria; Mannheimia haemolytica; Virulence
PubMed: 11750142
DOI: 10.1016/s0378-1135(01)00467-9 -
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 -
Letters in Applied Microbiology May 2017This study evaluated the potential of probiotic bacteria to inhibit growth and cell adhesion of the bovine respiratory pathogen Mannheimia haemoltyica serotype 1. The...
UNLABELLED
This study evaluated the potential of probiotic bacteria to inhibit growth and cell adhesion of the bovine respiratory pathogen Mannheimia haemoltyica serotype 1. The inhibitory effects of nine probiotic strains (Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus helveticus, Lactobacillus plantarum, Lactobacillus rhamnosus, Lactococcus lactis, Streptococcus thermophilus and two Paenibacillus polymyxa strains) against M. haemolytica were evaluated using a spot-on-lawn method. Probiotic strains were then tested for their adherence to bovine bronchial epithelial (BBE) cells and the ability to displace and compete against M. haemolytica on BBE. Except for S. thermophilus, all probiotic strains inhibited the growth of M. haemolytica, with zones of inhibition ranging between 12 and 19 mm. Lactobacillus strains and Lactococcus lactis displayed greater (P < 0·05) BBE adhesion compared with M. heamolytica (8·3%) and other probiotics (<2·2%). Strains of P. polymyxa and L. acidophilus caused the greatest reduction in M. haemolytica adherence, through both displacement and competition, compared with other probiotics. The results of this study suggest that probiotics may have the potential to colonize the bovine respiratory tract, and exert antagonistic effects against M. haemolytica serotype 1.
SIGNIFICANCE AND IMPACT OF THE STUDY
A common method to control bovine respiratory disease (BRD) in feedlots is through mass medication with antibiotics upon cattle entry (i.e. metaphylaxis). Increasingly, antimicrobial resistance in BRD bacterial pathogens has been observed in feedlots, which may have important implications for cattle health. In this study, probiotic strains were shown to adhere to bovine respiratory cells and inhibit the BRD pathogen M. haemolytica serotype 1 through competition and displacement. Probiotics may therefore offer a mitigation strategy to reduce BRD bacterial pathogens, in place of metaphylactic antimicrobials.
Topics: Animals; Anti-Bacterial Agents; Bacterial Adhesion; Cattle; Cattle Diseases; Cells, Cultured; Epithelial Cells; Lactobacillus acidophilus; Lactobacillus plantarum; Lacticaseibacillus rhamnosus; Mannheimia haemolytica; Pasteurellaceae Infections; Probiotics; Respiratory System; Serogroup
PubMed: 28178767
DOI: 10.1111/lam.12723 -
Current Microbiology Jun 2024Mannheimia haemolytica is recognized as principal pathogen associated with pneumonic pasteurellosis leading to huge economic losses to small ruminant farmers. Even...
Mannheimia haemolytica is recognized as principal pathogen associated with pneumonic pasteurellosis leading to huge economic losses to small ruminant farmers. Even though the disease causes huge economic losses, epidemiology of M. haemolytica is less studied, hindering the formulation of effective control strategies. Current study aimed to highlight molecular characterisation of M. haemolytica strains isolated from ovine pneumonic infection. M. haemolytica 27 isolates with two reference strains were characterised using capsular and virulence gene typing, multilocus sequence typing (MLST) and pulsed-field gel electrophoresis (PFGE) methods. M. haemolytica serotype A2 recognized as predominant serotype (74%) followed by A6 (11%) and A1 (5%) serotypes. Virulence gene profiling by PCRs showed dominance of all five virulent genes [such as adh and gcp (100% each)] followed by gs60 (88.8%), lktC (85.2%), tbpB (51.9%) and least nmaA gene (14.8%). MLST profiling delineated M. haemolytic isolates into 11 sequence types (STs) with most prevalent being ST37 (27.9%) and ST16 (23%) and nine new STs (ST37, 38, 39, 40, 41, 42, 47, 48, and 49). These new STs did not belong to any of the three clonal complexes (CC4, CC8 and CC28). ST16 was exclusively noted in A1 and A6 serotypes. Amongst 25 isolates, 22 pulsotypes (GD 0.88) recorded indicated variability of the M. haemolytica isolates in PFGE analysis. In conclusion, the study suggested dominance of M. haemolytica serotype A2 harbouring different virulent genes, diverse STs and pulsotypes responsible for pneumonic pasteurellosis frequently encountered in sheep.
Topics: Animals; Mannheimia haemolytica; Sheep; Sheep Diseases; India; Multilocus Sequence Typing; Pasteurellosis, Pneumonic; Serogroup; Electrophoresis, Gel, Pulsed-Field; Virulence Factors; Virulence; Phylogeny
PubMed: 38862704
DOI: 10.1007/s00284-024-03740-7 -
The Journal of Veterinary Medical... Jan 2019A Japanese Black calf became dehydrated on the first day of life and died on the third day. Gross examination revealed a large amount of yellowish-brown serous fluid in...
A Japanese Black calf became dehydrated on the first day of life and died on the third day. Gross examination revealed a large amount of yellowish-brown serous fluid in the abdominal cavity and whitish-yellow fibrin in the serosa of the abdominal organs. Patchy red spots were observed throughout the peritoneum, and the outer membrane of the umbilical arteries was dark red. Bacteriologically, Mannheimia haemolytica serotype 2 was isolated from the umbilical arteries and vein, liver, and kidney. Histopathology revealed inflammation with M. haemolytica serotype 2 in the outer membrane of the umbilical arteries and in the serosa of the bladder and intestinal tract. This is the first case of bovine peritonitis with histopathologic and immunohistochemical identification of M. haemolytica.
Topics: Animals; Animals, Newborn; Cattle; Cattle Diseases; Fatal Outcome; Mannheimia haemolytica; Pasteurellaceae Infections; Peritonitis
PubMed: 30487378
DOI: 10.1292/jvms.18-0625 -
Veterinary Microbiology Apr 2007Mannheimia haemolytica is the major causative agent of shipping fever, a severe pneumonia in cattle causing high morbidity and mortality. A prerequisite of successful... (Comparative Study)
Comparative Study
Mannheimia haemolytica is the major causative agent of shipping fever, a severe pneumonia in cattle causing high morbidity and mortality. A prerequisite of successful lung colonization by M. haemolytica is the necessity to adapt to the paucity of iron. The lack of genome information has precluded an assessment of the genetic repertoire available to M. haemolytica to adapt to low iron environments. To close this knowledge-gap, we have determined 90% of a virulent M. haemolytica serotype A1 genome sequence and produced a microarray in order to study gene expression under iron-limiting growth for 15, 30 and 60 min. M. haemolytica responded to iron limitation by the up-regulation of transcripts coding for receptors and ABC-type transporters of transferrin, haemoglobin, haem and siderophores. Real time PCR analysis of lung tissue from Mannheimia-infected calves demonstrated the in vivo transcription of two potential haemoglobin receptors, hmbR1 and hmbR2. The relative hmbR1 and hmbR2 transcript levels in the infected lung tissue were comparable to the induced levels observed under iron-limiting growth, demonstrating in vivo induction of receptor transcription in the context of an infection. When the iron response of M. haemolytica was compared to the iron response of Pasteurella multocida, another pathogen colonizing the bovine lung, only few homologous genes were induced in both organisms. These included the haemoglobin receptor hmbR2 and the periplasmic transport systems yfeABCD and fbpABC. The comparative analysis suggests that the two pathogens use different strategies to adapt to the iron-limiting environment in the bovine host.
Topics: Animals; Blotting, Northern; Cattle; Cattle Diseases; Gene Expression Regulation, Bacterial; Heme; Hemoglobins; Iron; Lung Diseases; Mannheimia haemolytica; Oligonucleotide Array Sequence Analysis; Pasteurella multocida; Pneumonia of Calves, Enzootic; RNA, Bacterial; Reverse Transcriptase Polymerase Chain Reaction
PubMed: 17240088
DOI: 10.1016/j.vetmic.2006.12.013 -
Veterinary Immunology and... Nov 2002Fibrinogen-binding proteins were found in the culture supernatants of Mannheimia haemolytica serotype 1 (ATCC 43270) and Pasteurella trehalosi serotype 10 (ECO-100)....
Fibrinogen-binding proteins were found in the culture supernatants of Mannheimia haemolytica serotype 1 (ATCC 43270) and Pasteurella trehalosi serotype 10 (ECO-100). Sheep fibrinogen was biotinylated and shown to bind to proteins in the culture supernatants by modified western blot. Fibrinogen-binding proteins in the culture supernatant may be important virulence factors leading to the characteristic fibrinous pneumonia caused by these organisms and may be critical antigenic targets for immune prophylaxis.
Topics: Animals; Bacterial Proteins; Blotting, Western; Culture Media, Conditioned; Fibrinogen; Mannheimia haemolytica; Pasteurella; Protein Binding; Sheep
PubMed: 12406660
DOI: 10.1016/s0165-2427(02)00222-2