We analyze theoretically the quantization of conductance
occurring with cold atoms trapped in two reservoirs connected by a
constriction within which an attractive gate potential is added.
We show that the Bose statistics strongly enhances the effect
compared to fermions. We focus on temperatures slightly above the
condensation threshold in the reservoirs, which contain a thermal
gas. The Bose statistics leads to conductance plateaux whose large
values depend on the thermodynamics of the gas in the reservoirs.
We highlight the key role of weak repulsive interactions between
the bosons in preventing them from collapsing into the
constriction. We also point out the differences in the
thermoelectric effects occurring with bosons and fermions in the
quantized conductance regime.