  The effects of trimer continuum resonances are considered in the three-body
recombination rate of a Bose system at finite energies for large and negative
two-body scattering lengths ($a$). The thermal average of the rate allows to
apply our formula to Bose gases at ultra-low temperatures. We found a good
quantitative description of the experimental three-body recombination length of
cesium atoms to deeply bound molecules up to 500 nK. Consistent with the
experimental data, the increase of the temperature moves the resonance peak of
the three-body recombination rate to lower values of $|a|$ exhibiting a
saturation behavior.
