INVESTIGADORES
PALACIOS Maria Gabriela
congresos y reuniones científicas
Título:
Comparison of immune structure and function of nestling and adult tree swallows: patterns and processes.
Autor/es:
PALACIOS, M. G.; CUNNICK, J. E.; VLECK, D.; VLECK, C. M.
Lugar:
Veracruz, Mexico
Reunión:
Congreso; 4th North American Ornithological Conference.; 2006
Institución organizadora:
Ornithological Societies of North America
Resumen:
Immature individuals are generally more susceptible to infection than adults. Studies in poultry show that many aspects of the immune system are poorly developed in young, but little is known about development of the immune system in free-living birds. Different components might develop at different rates depending on the relative costs (e.g., effects on growth rate) and benefits (disease prevention) associated with their development. We compared immune structure and function of nestling and adult tree swallows to test the hypothesis that components of innate immunity are more fully developed in nestlings than components of acquired immunity, because innate immunity constitutes the first line of defense and may be less costly to develop. Nestlings had lower total white blood cell counts and percentage of lymphocytes, but higher percentage of eosinophils than adults. No difference was detected in heterophils, basophils, and monocytes, important in innate immunity. However, nestlings had lower titers of natural antibodies, complement-mediated cell lysis, and proliferation of T-lymphocytes in response to phytohemagglutinin than adults; but no difference in proliferation of T-lymphocytes in response to concanavalin A or proliferation of B-lymphocytes. Our results only partially support our hypothesis and suggest a complex pattern of development of immune structure and function.