Most of the publications on Anisakis simplex (Rudolphi, 1809) focus upon systematic aspects and zoonotic risk but there is lack of detailed information on infection and cellular immune response of the gonads. The current investigation detected whether gonadal infection by A. simplex affects reproductive development and how Atlantic mackerel, Scomber scombrus (L.), responds immunologically. Thirty-four specimens out of 62 S. sc...