background and aims: avian metapneumovirus (ampv) is rna virus responsible for upper respiratory disease in poultry which is usually accompanied by secondary bacterial infections. in iran, some molecular and serological studies indicated that ampv infection occurred in commercial poultry industry. materials and methods: in this study ampv was molecularly identified and characterized in an affec...

background and objectives: diarrheagenic escherichia coli (dec) strains are a major cause of intestinal syndromes in the developing countries. the aim of this study was to determine the prevalence of enterotoxigenic e. coli (etec) and enteroinvasive e. coli (eiec) in relation to phylogenetic background from patients with diarrhea. materials and methods: a total of 110 e. coli isolates were obta...

boophilus genus ticks are responsible for transferring some pathogens and reducing production factors in cattle. tropomysin (tpm) protein has actin regulator activity and playing important role in immune and allergic reactions. the main goal is to determine different aspects of phylogenetic, similarity, homology, structure and allergenicity of tpm protein. in prior study, we identified tpm by u...

the aim of the present study was to find the best or optimum topology of six chicken populations, which were genotyped based on nine highly polymorphic microsatellite markers. to reach this goal, different genetic distances based on infinite allele model (iam), stepwise mutation model (smm) and drawing phylogentic trees on un-weighted pair-group method using arithmetic averages (upgma) method w...

sixteen avian influenza (ai) h9n2 viruses were isolated from disease outbreaks in different parts of iranduring (1998–2001). these ai isolates were used for pathogenicity, haemagglutinin (ha) gene variation andphylogenetic analysis. results in both pathogenicity tests and ha gene cleavage site sequence detectionrepresented a non-highly pathogenic feature for all iranian ai isolates studied. the...

There are two paradigms for the phylogenetic analysis of multi-locus sequence data: one which forces all genes to share the same underlying history, and another that allows genes to follow idiosyncratic patterns of descent from ancestral alleles. The first of these approaches (concatenation) is clearly a simplified model of the actual process of genome evolution while the second (species-tree m...

In macroevolutionary studies, different approaches are commonly used to measure phylogenetic signal--the tendency of related taxa to resemble one another--including the K statistic and the Mantel test. The latter was recently criticized for lacking statistical power. Using new simulations, we show that the power of the Mantel test depends on the metrics used to define trait distances and phylog...

The study of genome rearrangement is much harder than the corresponding problems on DNA and protein sequences, because of the occurrences of numerous combinatorial structures. By explicitly exploring these combinatorial structures, the recently developed adequate subgraph theory shows that a family of these structures, adequate subgraphs, are informative in finding the optimal solutions to the ...

The tendency for more closely related species to share similar traits and ecological strategies can be explained by their longer shared evolutionary histories and represents phylogenetic conservatism. How strongly species traits co-vary with phylogeny can significantly impact how we analyze cross-species data and can influence our interpretation of assembly rules in the rapidly expanding field ...

Phylogenetic Generalized Least Square (PGLS) is the tool of choice among phylogenetic comparative methods to measure the correlation between species features such as morphological and life-history traits or niche characteristics. In its usual form, it assumes that the residual variation follows a homogenous model of evolution across the branches of the phylogenetic tree. Since a homogenous mode...