  We obtain constraints on possible anomalous interactions of the top quark
with the electroweak vector bosons arising from the precision measurements at
the Z pole. In the framework of $SU(2)_L \otimes U(1)_Y$ chiral Lagrangians, we
examine all effective CP-conserving operators of dimension five which induce
fermionic currents involving the top quark. We constrain the magnitudes of
these anomalous interactions by evaluating their one-loop contributions to the
Z pole physics. Our analysis shows that the operators that contribute to the
LEP observables get bounds close to the theoretical expectation for their
anomalous couplings. We also show that those which break the $SU(2)_C$
custodial symmetry are more strongly bounded.
