Health monitoring in birds using bio-loggers and whole blood transcriptomics

Monitoring and early detection of emerging infectious diseases in wild animals is of crucial global importance, yet reliable ways to measure immune status and responses are lacking for animals in the wild. Here we assess the usefulness of bio-loggers for detecting disease outbreaks in free-living birds and confirm detailed responses using leukocyte composition and large-scale transcriptomics. We simulated natural infections by viral and bacterial pathogens in captive mallards (Anas platyrhynchos), an important natural vector for avian influenza virus. We show that body temperature, heart rate and leukocyte composition change reliably during an acute phase immune response. Using genome-wide gene expression profiling of whole blood across time points we confirm that immunostimulants activate pathogen-specific gene regulatory networks. By reporting immune response related changes in physiological and behavioural traits that can be studied in free-ranging populations, we provide baseline information with importance to the global monitoring of zoonotic diseases.

Automated summary

This study evaluates the reliability of using bio-loggers to detect disease outbreaks in free-living birds by combining leukocyte composition and transcriptomics. It was found that body temperature, heart rate, and leukocyte composition change reliably during an acute immune response, and immune stimulants activate pathogen-specific gene regulatory networks as confirmed by genome-wide gene expression profiling. Reporting changes in physiological and behavioral traits related to immune response provides important baseline information for global monitoring of zoonotic diseases.