Meeting Abstract

89.5  Wednesday, Jan. 7  Trade-off between maternal immunocompetence and offspring viability in zebra finches RUTKOWSKA, Joanna*; MARTYKA , Rafal; CICHON, Mariusz; Institute of Environmental Sciences, Jagiellonian University joanna.rutkowska@uj.edu.pl

The immune system is an important player in individual physiological trade-offs; however, intergenerational effects of immunocomeptence have rarely been explored. Immunocompetent mothers should produce high quality offspring, especially if maternal immunological agents present in the eggs protect embryos and later nestlings against pathogens. However, maternal immune response could come at the cost of draining resources from breeding investments. We examined the relationship between the strength of maternal antibody production in response to novel antigen and offspring performance and survival in three separate experiments. In each of them, the female immune system was challenged with sheep red blood cells (SRBCs), and the response was scored using hemagglutination test. Experiments differed in two aspects: timing of immune challenge in relation to breeding and degree of offspring competition within broods that was manipulated by experimental synchronization of hatching. In all cases, offspring survival until adulthood was negatively related to maternal antibody titers. Because that effect was observed among offspring of females mounting an immune response both during as well as a few months before breeding, we conclude that maternal antibody production per se is not directly responsible for lower offspring viability. Comparison of the two experiments differing in the level of offspring competition revealed that higher competition within synchronized broods strengthened the negative relationship between maternal antibody titers and offspring survival. We conclude that high maternal immunocompetence is associated with lower offspring viability irrespective of current maternal immune status.