SpermatocytesSpermatogenesisMeiotic Prophase ISynaptonemal ComplexMeiosisPachytene StageSpermatidsTestisSpermatozoaChromosomesSertoli CellsSpermatogoniaSeminiferous TubulesSeminiferous EpitheliumProphaseChromosome PairingBlood-Testis BarrierInfertility, MaleSperm CountGerm CellsDipteraLeydig CellsMetaphaseSex ChromosomesY ChromosomeFertilityTriethylenemelamineSalamandridae