We study the cancellations among Feynman diagrams that implement the Ward and
Slavnov-Taylor identities corresponding to the conserved supersymmetry current
in supersymmetric quantum field theories. In
particular, we show that the Faddeev-Popov ghosts of gauge- and supersymmetries
never decouple from the physical fields, even for abelian gauge groups.
The supersymmetric Slavnov-Taylor identities provide efficient consistency
checks for automatized calculations and can verify the supersymmetry of
Feynman rules and the numerical stability of phenomenological predictions
simultaneously.
