We study emission and absorption of radiation by non-relativistic electrons within the framework of a Lorentz-breaking electrodynamics in dimensions. We have realised that Planck-type law acquires extra terms proportional to the violating parameters: For the CPT-odd model, the leading extra terms appear to be linear or quadratic in these violating parameters according to the background vector is parallel or perpendicular to the photon wave-vector. In the CPT-even case a linear correction shows up. Besides these deviations in the black-body spectra, those violations may be also probed through a difference in the photon mean occupation number for the two modes. Our results also indicate that such violations are better probed at very low temperatures, where their effects on the thermal spectra are largely enhanced.