title: Effects of parental effort on blood stress protein HSP60 and immunoglobulins in female blue tits: a brood size manipulation experiment.
abstract: 1. Physiological stress in animals may impose a limit for investment in current reproduction in the wild. A brood manipulation experiment was conducted in a population of blue tits Cyanistes caeruleus to study the effect of parental effort on changes in two types of proteins related with stress: the blood stress protein HSP60 and the plasma immunoglobulins. 2. Levels of HSP60 were reduced across the experiment for females attending reduced broods, and females attending enlarged broods experienced a reduction of immunoglobulin levels. Moreover, the overall changes in the levels of both proteins were positively related. 3. By controlling for the change in immunoglobulin levels we found an increase in HSP60 for females in the enlarged treatment, presumably to offset deleterious effects derived from increased effort. 4. Maternal effort was able to partially compensate for the effect of treatment as nestlings did not differ in mass and levels of immunoglobulins and HSP60 among treatments. 5. Physiological stress as reflected in stress and immunoglobulin proteins may limit maternal effort in breeding blue tits.
authors.affiliation: Departamento de Ecología Evolutiva, Museo Nacional de Ciencias Naturales-CSIC, Madrid, Spain. santiagom@mncn.csic.es
authors.forename: Santiago
authors.initials: S
authors.lastname: Merino
authors.forename: Juan
authors.initials: J
authors.lastname: Moreno
authors.forename: Gustavo
authors.initials: G
authors.lastname: Tomás
authors.forename: Javier
authors.initials: J
authors.lastname: Martínez
authors.forename: Judith
authors.initials: J
authors.lastname: Morales
authors.forename: Josué
authors.initials: J
authors.lastname: Martínez-de la Puente
authors.forename: José Luis
authors.initials: JL
authors.lastname: Osorno
mesh_terms: D000818:Animals; D018834:Chaperonin 60 / Q000097:blood / Q000502:physiology*; D052284:Clutch Size; D005260:Female; D015870:Gene Expression / Q000502:physiology; D016787:Haemosporida / Q000302:isolation & purification / Q000472:pathogenicity; D007136:Immunoglobulins / Q000097:blood / Q000502:physiology*; D009425:Nesting Behavior / Q000502:physiology*; D046109:Passeriformes / Q000276:immunology / Q000469:parasitology / Q000502:physiology*; D013312:Stress, Physiological / Q000276:immunology / Q000503:physiopathology / Q000662:veterinary*
chemical_list: D018834:Chaperonin 60; D007136:Immunoglobulins