Different bacteria in different environments

Bacteria are ubiquitous all around us and are considered the first life form on the earth. Like other organisms, they are evolving with the passage of time that has resulted either in promoting the health of the host or causing the infectious diseases in the past, now and much likely in future. A number of efforts have been made to enumerate the baseline information of bacteria hosted by birds reared under different managmental practices; controlled houses and open farms. All of these have been limited to certain commensals and/or pathogens under man made physical laboratory conditions. Due to lack of adequate culturing techniques in the past, either known or available, only few bacteria and their subsequent diseases are known.
However, with the advancement of science, genomes sequencing techniques and sequence analysis tools have been available to define culture independent analysis of bacterial communities in the environment/host. Recently, we have evaluated the unbiased identification of bacteria present in birds reared under different managmental conditions, captive poultry in open house condition as well as broiler and breeders in controlled house environment. Genome region (16S rRNA) which is considered highly conserved among prokaryotes but distinct among each bacterial species and genera, have been used to differentiate bacterial community in both apparently healthy and diseased birds with history of clinically undiagnosed respiratory disease. Understanding the bacterial ecology harbored by diseased or health birds is important to a) enumerate and differentiate bacterial community present in the environment hosting the birds, b) correlate pathogen or commensals interaction with each other and vice versa, c) improve clinical and molecular diagnostics, and d) devising subsequent health and disease control strategies.
Though, there were some common organisms too in each management system, however, there was a significant difference in dominant genera in both type of group of birds; diseased and healthy. Similarly, there was a difference in major species of bacteria in abundance for each type and group of birds. Healthy birds were found to have more diverse bacterial community than diseased birds in open house farms, whereas, diseased birds were found to have more diversity in controlled farms than healthy. In both type of management system, healthy birds community was more similar with one type of bacteria displacing the others, whereas, diseased birds were shown to have more than one candidate pathogens.
In simple words, the proportion of each bacterium in total community was less in apparently healthy birds than diseased birds. Overall, the open house farm birds were found to have more diverse bacterial population than controlled house farms. Likewise, a number of previously unreported organism/novel and their association to either clinically health status or disease status have been found. The association of pathogen to clinical outcome warrants further investigation into this field of molecular science and provides an opportunity to made surveillance of these pathogen widely throughout Pakistan, aiding clinical diagnostician and laboratory specialist as well as farmers and other stakeholders.
MUHAMMAD ZUBAIR SHABBIR
UVAS, Lahore