OBJECTIVE To perform a comprehensive phenotypic characterisation of 35 isolates of bacteria previously identified as haemolytic Pasteurella-Actinobacillus and obtained from cattle and sheep. DESIGN The 35 isolates that had been obtained from Australian animals, 30 from cattle and five from sheep, were compared with reference strains of the five recognised species of the genus Mannheimia--M. h...

The mosaic structure and molecular evolution of the leukotoxin operon (lktCABD) was investigated by nucleotide sequence comparison of the lktC, lktB, and lktD genes in 23 Mannheimia (Pasteurella) haemolytica, 6 Mannheimia glucosida, and 4 Pasteurella trehalosi strains. Sequence variation in the lktA gene has been described previously (R. L. Davies et al., J. Bacteriol. 183:1394-1404, 2001). The...

Mannheimia haemolytica, Pasteurella multocida, and Bibersteinia trehalosi have been identified in the lungs of pneumonic bighorn sheep (BHS; Ovis canadensis). Of these pathogens, M. haemolytica has been shown to consistently cause fatal pneumonia in BHS under experimental conditions. However, M. haemolytica has been isolated by culture less frequently than the other bacteria. We hypothesized th...

The antibody response to various combined polyvalent Pasteurella haemolytica vaccines was studied in sheep and cattle. In sheep, certain oil adjuvant vaccines gave rise to a better antibody response to P. haemolytica than an A1(OH)3-adsorbed vaccine. This finding, however, was not consistent for all serotypes, and with respect to P. multocida, oil adjuvants had no advantage. Furthermore, it was...

A Pasteurella haemolytica A1 gene involved in the biosynthesis of a moiety on the core of the lipopolysaccharide molecule has been cloned and characterized. Escherichia coli clones which carry this gene showed an alteration of its lipopolysaccharide migration profile on tricine SDS-PAGE and exhibited resistance to the core-specific phage U3. In addition, lipopolysaccharide extracted from the E....

The purpose of this study was to determine if Pasteurella haemolytica can directly injure bovine pulmonary endothelial cells (EC) and if neutrophils have a beneficial or detrimental role in bacterium-EC interaction. Various combinations of live P. haemolytica, heat-killed P. haemolytica, anti-P. haemolytica immune serum, polymyxin B, and bovine neutrophils were added to confluent monolayers of ...

Pasteurellosis is one of the important economic diseases in ruminants, especially in cows and buffaloes. It is caused by Pasteurella multocida and occasionally by Mannheimia haemolytica. The aim of this study was to isolate Pasteurella multocida from lungs with probable mentioned bacterial agents in cows and buffaloes in Urmia's slaughter house. 240 lung samples over a period of 12 months were ...

conclusions ethanol extracts of p. granatum (pericarp, leaves, flowers, seeds) have antibacterial effects against p. haemolytica which has shown resistance to all studied antibiotics. background continuous researches on drugs that solve the problem of growing number of resistant bacteria are important. objectives this research aims to investigate the effectiveness of anti-bacterial properties s...

An enzyme-linked immunosorbent assay (ELISA) was developed for detection of bovine serum antibodies to the cytotoxin (leukotoxin) of Pasteurella haemolytica. A partially purified, cytotoxic, and immunogenic protein obtained from supernatants of logarithmic-phase P. haemolytica was used as the ELISA antigen. Preadsorption of sera with various cytotoxic, somatic, and capsular antigen preparations...

A total of 184 tracheas, 147 livers, 150 spleens and 148 hearts from apparently healthy and dead chickens were sampled and the bacterial flora was determined. The bacteria most commonly cultured from these four organs of healthy birds were Staphylococcus spp., Streptococcus spp., and Escherichia coli. Escherichia coli, Aeromonas spp., Staphylococcus spp., Proteus spp., and Citrobacter spp., wer...