  The ratios of yields of anti-baryons to baryons probes the mechanisms of
baryon-number transport. Results for $\bar{\rm p}/{\rm p}$, $\bar{\rm
\Lambda}/{\rm \Lambda}$, $\rm\bar{\Xi}$$^{+}/{\rm \Xi}^{-}$ and
$\rm\bar{\Omega}$$^{+}/{\rm \Omega}^{-}$ in pp collisions at $\sqrt{s} = 0.9$,
2.76 and 7 TeV, measured with the ALICE detector at the LHC, are reported.
Within the experimental uncertainties and ranges covered by our measurement,
these ratios are independent of rapidity, transverse momentum and multiplicity
for all measured energies. The results are compared to expectations from event
generators, such as PYTHIA and HIJING-B, that are used to model the particle
production in pp collisions. The energy dependence of $\bar{\rm p}/{\rm p}$,
$\bar{\rm \Lambda}/{\rm \Lambda}$, $\rm\bar{\Xi}$$^{+}/{\rm \Xi^{-}}$ and
$\rm\bar{\Omega}$$^{+}/{\rm \Omega^{-}}$, reaching values compatible with unity
for $\sqrt{s} = 7$ TeV, complement the earlier $\bar{\rm p}/{\rm p}$
measurement of ALICE. These dependencies can be described by exchanges with the
Regge-trajectory intercept of $\alpha_{\rm {J}} \approx 0.5$, which are
suppressed with increasing rapidity interval ${\rm \Delta} y$. Any significant
contribution of an exchange not suppressed at large ${\rm \Delta} y$ (reached
at LHC energies) is disfavoured.
