Meeting Abstract
Neonates lack adaptive immunity and are vulnerable to pathogens. Mothers can transfer passive immunity to offspring by transmitting antibodies (Abs) via milk or yolk. Mothers previously or currently infected with a pathogen transfer Abs to newborns, granting them immunological protection until they can synthesize their own. In birds, Abs are deposited before eggshell formation within the mother’s oviduct. Similarly, mothers may transmit pathogens that colonize the oviduct. It was recently found that wild eastern bluebirds (Sialia sialis) are common hosts of the avian pathogen Mycoplasma gallisepticum (MG). We
sampled 40 nestlings laid by MG-positive mothers and found 15% of nestlings were positive for MG Abs. The MG bacterium is known to be vertically transmitted in poultry. It colonizes the oviducts of infected hens and is transmitted to embryos during egg formation. My study will monitor a population of eastern bluebirds to test: the adaptive nature of specific MG antibodies, if infected female bluebirds harbor MG bacteria in their oviduct and transmit MG to their eggs, and the differences in both antibody and disease transmission between first and second broods. I will quantify MG Ab concentrations in eggs, nestlings, and adults. I will use PCR to identify active MG infections in female birds. If egg transmission of MG is occurring, then maternal Abs would provide critical immunological support to embryos exposed during development. This study will provide insight into non-genetic, maternal effects on offspring survival and growth in response to a costly infection.
