Domestication Effects on Immune Response: Comparison of Phytohemagglutinin-Induced Skin Swelling in Domesticated Bengalese Finch and Its Wild Ancestor, White-Rumped Munia.

Abstract

The domesticated Bengalese finch (Lonchura striata var. domestica) exhibits more complex songs and altered physiological and behavioral traits compared with its wild ancestor, the white-rumped munia (Lonchura striata). Domestication has been suggested to be associated with immune function, and domestication-related physiological and behavioral traits are thought to co-vary with immune traits. Comparing immune responses between the Bengalese finch and the white-rumped munia provides an opportunity to explore phenotypic differences associated with domestication. In this study, we assessed cell-mediated immune responses using phytohemagglutinin (PHA), a lectin that induces local skin swelling. This PHA-induced swelling (PHA response) is a widely used index of T cell-mediated immunity in ecological immunology. Our results showed that the Bengalese finch exhibited a significantly greater PHA response than the white-rumped munia, indicating higher cell-mediated immune activity in the domesticated birds. These findings suggest a possible association between immune function and domestication-related phenotypic changes, including fearfulness, song complexity, and stress responsiveness.