We present a QCD analysis of the strange and charm contributions to the
neutrino deep inelastic structure function xF3. We show that next-to-leading
order effects, which are relatively important for F2, play a lesser role in
the case of xF3. The neutrino--antineutrino difference xF3ν−xF3νˉ provides a new determination of the strange density, which
exhibits some advantages with respect to other traditional methods.Comment: 12 page