Infection with Toxoplasma gondii does not elicit predator aversion in male mice nor increase their attractiveness in terms of mate choice

Abstract

Behavioral manipulation hypothesis posits that some parasites induce behavioral changes in the host to increase transmission efficiency of the parasite. Protozoan parasite Toxoplasma gondii infecting rats has been widely studied in this context. T. gondii increases attractiveness of infected male rats and reduces innate aversion of rats to cat odor, likely increasing transmission of the parasite by sexual and trophic routes respectively. It is currently unexplored if T. gondii induces gain of male attractiveness in experimental models other than rats. Here we show that laboratory infection of two strains of mice does not induce behavioral manipulation. Moreover, T. gondii infection results in reduction of male attractiveness in one of the strains. In agreement with this observation, T. gondii infection also fails to induce reduction in innate aversion to cat odors in mice. Effects of the parasite on mice mate choice are similar to effects of several other parasites in this animal model. Thus, behavioral change induced by the parasite may be specific to the rodent species.