colibacillosis caused by e.coli is one of the most common illnesses in commercial chickens and induce high financial losses in the poultry industry due to morbidity, mortality and antibiotic expenses because of overuses. e.coli can mostly cause disease as a secondary or opportunistic pathogen, while certain strains with specific virulence factors even as primary pathogen can cause colibacillosi...

Isolates of Rhynchosporium secalis collected from two experimental barley populations were scored for putative isozyme, colony color, and virulence loci. Allelic frequencies, multilocus haplotype frequencies, and multilocus genetic structure differed in the two populations of R. secalis; haplotypes also differed widely from each other in virulence. The average virulence of isolates collected fr...

Background: A most common opportunistic pathogen, Pseudomonas aeruginosa is present in both humans and animals and responsible for various nosocomial infections and healthcare settings related infections. Different virulence genes like; oprL (membrane lipoprotein L) and toxA (exotoxin A i.e. ETA) in P. aeruginosa, assist in its pathogenicity, toxicity and contribute to high antibiotic resistanc...

pseudomonas aeruginosa as an opportunistic pathogen produces several virulence factors. the most important of these factors are exotoxin a and type iii secretion system (t3ss). the aim of this study was to determine the frequency of toxa, exou and exos genes among clinical isolates of p. aeruginosa. in this cross-sectional study from september 2011 to february 2012, 156 p. aeruginosa isolates w...

Global-scale data on the Oligocene to Recent planktic foraminifers and coccoliths from the tropical Pacific and Atlantic Oceans are employed for quantitative testing of alternative models (Red Queen and Stationary Hypotheses) of the relationship between speciation rates, extinction rates, taxonomic diversity, abiotic events, and history of the paleosystem. The results demonstrate that although ...

Brucellosis is a widespread zoonotic disease causing considerable economic and public health problems. Despite animal vaccination, brucellosis remains endemic in some areas such as Iran, especially in the western Iranian province of Hamadan. We sought to detect some of the most common virulence-associated genes in Brucella isolated from human blood cultures to determine the prevalence of some v...

Background: Although Escherichia coli (E. coli)is a part of intestinal normal microflora of warm-blooded animals, includingpoultry, outbreaks occur in poultry raised below standard sanitation and duringthe course of respiratory or immunosuppressive diseases. Avian pathogenic E.coli (APEC) harbors several genes associated with virulence andpathogenicity. APEC strains are responsible for some dis...

beauveria bassiana (balsamo) vuillemin is an important natural regulator of insect populations. identification of a suitable molecular marker for detecting a virulent phenotype on a target pest would be useful in screening for effective isolates against the pest. nine isolates of b. bassiana were tested for their virulence to adults of tribolium castaneum (herbst) in laboratory bioassay with 1×...

background and objectives: pseudomonas aeruginosa possesses a variety of virulence factors that may contribute to its pathogenicity. the aim of this study was to evaluate opri , oprl and toxa genes for pcr identification of clinical p. aeruginosa . in order to find out any relation between special virulence factors and special manifestation of p. aeruginosa infections, we detected virulence fac...