The energetic cost of social behavior in mice under activation of the nonspecific immunity

: Using originally designed low inertial open circuit respirometer, we studied influence of the bacterial endotoxin on the bioenergetic gain of male mice, which they showed after 15 min pair-wise test. Injection of lipopolysaccharide (LPS) provided increase of the post pair-wise test energy metabolism and increase of the relative energy cost of each agonistic act in dominant males. Significant correlation between energy response and number of agonistic acts in the pair-wise test was found only for LPS treated males. Spontaneous activity measured before social conflict and non-agonistic behavior during pair-wise test did not correlate with energy metabolism. Since all behavioral acts need energy and since the significant correlation between energy response and behavioral activity was found only for the agonistic behavior we assume these relationships being a result of synergetic influence on the energy metabolism of both the nonspecific immune response on LPS and neuroendocrine accompaniment of the intermale aggression.