  The derivation of the 1/N_c expansions for the baryon vector and axial-vector
currents, in the SU(3) symmetry limit and including perturbative SU(3)
breaking, is reviewed. Symmetry breaking effects in the hyperon semileptonic
decay form factors are reanalyzed. Fits to experimental data yield corrections
to the leading vector and axial-vector form factors consistent with
expectations. The values of the Cabibbo-Kobayashi-Maskawa matrix elements
V_{ud} and V_{us} also extracted from the analysis are comparable to the ones
recommended by the Particle Data Group.
