  We have estimated fluxes of neutrinos and gamma-rays that are generated from
decays of charged and neutral pions from a pulsar surrounded by supernova
ejecta in our galaxy, including an effect that has not been taken into
consideration, that is, interactions between high energy cosmic rays themselves
in the nebula flow, assuming that hadronic components are the energetically
dominant species in the pulsar wind. Bulk flow is assumed to be randomized by
passing through the termination shock and energy distribution functions of
protons and electrons behind the termination shock are assumed to obey the
relativistic Maxwellians. We have found that fluxes of neutrinos and gamma-rays
depend very sensitively on the wind luminosity, which is assumed to be
comparable to the spin-downluminosity. In the case where B=10^{12}G and P=1ms,
neutrinos should be detected by km^3 high-energy neutrino detectors such as
AMANDA and IceCube. Also, gamma-rays should be detected by Cherenkov telescopes
such as CANGAROO and H.E.S.S. as well as by gamma-ray satellites such as GLAST.
On the other hand, in the case where B=10^{12}G and P=5ms, fluxes of neutrinos
and gamma-rays will be too low to be detected even by the next-generation
detectors. However, even in the case where B=10^{12}G and P=5ms, there is a
possibility that very high fluxes of neutrinos may be realized at early stage
of a supernova explosion (t \le 1yr), where the location of the termination
shock is very near to the pulsar. We also found that there is a possibility
that protons with energies \sim 10^5 GeV in the nebula flow may interact with
the photon field from surface of the pulsar and produce much pions, which
enhances the intensity of resulting neutrinos and gamma-rays.
