FORSMAN, A.M.*; SAKALUK, S.K.; VOGEL, L.A.; ARQUETTE, R.F.; THOMPSON, C.F.; Illinois State University, Normal; Illinois State University, Normal; Illinois State University, Normal; Illinois State University, Normal; Illinois State University, Normal: Do measures of female condition predict survival, condition, and immune response of nestling house wrens (Troglodytes aedon)?
Advances in molecular techniques allow investigators to assess quantitatively the physiological condition of free-living organisms. For example, avian serum proteins may be separated by gel electrophoresis into five distinct classes (pre albumin; albumin; alpha-, beta-, and gamma globulins) and their relative quantities calculated by densitometric analysis of electrophoretic bands. Total serum protein concentration and levels of each protein class often differ between healthy and diseased individuals, making them potentially useful in assessing health status. Immunological assays have also been developed to assess robustness of both innate and adaptive aspects of immune function. We used these techniques to test the hypothesis that female condition is positively correlated with nestling condition, immune response, and survival until nest-leaving in house wrens (Troglodytes aedon) breeding in central Illinois. As measures of adult and nestling condition, we used body weight, hematocrit, total serum protein concentration, and levels of individual serum protein fractions. We determined total protein concentration of serum samples by Lowry assay and serum protein profiles by electrophoresis and densitometry. Cell-mediated immune response in nestlings was assessed by measuring wing-web swelling resulting from a subcutaneous injection of phytohaemagglutinin (PHA). We also injected other nestlings with the T-cell dependent antigen, tetanus toxoid, to activate the humoral immune system. Humoral response was measured as antigen-specific antibody production by ELISA. The results of this study are discussed in the context of technique efficacy and diagnostic potential.
