Parasiticidal activity of Haemaphysalis longicornis longicin P4 peptide against Toxoplasma gondii

► The effects of the Haemaphysalis longicornis longicin P4 peptide on the morphology state of Toxoplasma gondii tachyzoites were examined. ► Tachyzoites incubated with longicin P4 had been induced the pathological changes of cell morphology. ► The number of tachyzoites proliferated in mouse macrophage cell line (J774A.1) was significantly decreased by incubation with longicin P4. ► These findings suggested that longicin P4 conceivably impaired parasite membranes, leading to the destruction of tachyzoites in J774A.1 cells. ► Longicin P4 hold great promise for studying as an anti-toxoplasmosis molecule.