We specifically considered the case in which one of the required mutations exists as a small proportion of the avian within-host viral population, or in the viral populations from the >20 mammalian hosts in which A/H5N1 infections have been observed (22 25), so that they would not be detected by the usual consensus sequencing techniques.
Indeed, a substantial proportion of socially monogamous avian species is sexually promiscuous, with the result that there are >10 % of extra-pair offspring and/or broods (Birkhead and Møller 1998; Petrie and Kempenaers 1998; Westneat and Stewart 2003).
There was a higher proportion of subjects reporting their source of avian influenza information from village chiefs (+5.6% in Prey Veng, p = 0.001; +4.5% in Kampong Cham, p = 0.01), and a small apparent decrease from health centers in Prey Veng (−6.2% in Prey Veng; p = 0.002), and village animal health workers (−7.8% in Prey Veng, p = 0.001; −6.4% in Kampong Cham, p = 0.004).
Our overall findings suggest that the number of β-keratins and the relative proportion of β-keratins in each subfamily influenced the composition of avian skin appendages and therefore their structural properties.
The proportions of mutations for avian isolates of both NCBI and Ottenby sequences were pooled separately, which resulted in six replicates in the NCBI group and five replicates in the Ottenby group.
For both ducks and in-contact chickens, bird-level seroprevalence (proportion of study birds with antibodies to avian influenza [H5]) and flock-level seroprevalence (in which at least 1 study bird had antibodies) were calculated for each of the 7 sampling periods and pooled across the entire study period.
As it was not known whether biomass composition of avian cells is comparable to other examined cells, we first determined relative proportions of biomass components experimentally.
Negative selection was detected in a large proportion of amino acid sites in the examined avian β-defensin (11.4 40.9 %) and cathelicidin (9.7 24.7 %) genes (Fig. 7a, Additional file 3).
M. chelonae (identified by DNA sequencing) was the causative agent for most of the definite cases (n = 3, 75%), and the largest proportion of possible cases was caused by M. avian complex bacteria (n = 5, 41.7%).
