We investigate how magnetic properties of Magellanic-type and perturbedobjects are related to star-forming activity, galactic type, and mass. Wepresent radio and magnetic properties of 5 Magellanic-type and 2 peculiarlow-mass galaxies observed at 4.85 and/or 8.35 GHz with the Effelsberg 100-mtelescope. The sample is extended to 17 objects by including 5 Magellanic-typegalaxies and 5 dwarf ones. The radio emission of low-mass galaxies at 4.85/8.35GHz is closely connected with their optical discs. The strengths of totalmagnetic field are within 5-9 \mu G, while the ordered fields reach 1-2 \mu G.The magnetic field strengths are well correlated with the surface density ofSFR and manifest a power-law relation with an exponent of 0.25 extending asimilar relation found for dwarf galaxies. The production of magnetic energyper supernova event is similar for all the various galaxies. It constitutesabout 3% of the individual SN energy release. We show that the total magneticfield energy in galaxies is almost linearly related to the galactic gas mass,which indicates equipartition of the magnetic energy and the turbulent kineticenergy of the ISM. The Magellanic-type galaxies fit very well with theradio-infrared relation constructed for surface brightness of galaxies ofvarious types, including bright spirals and interacting objects. We found thatthe typical far-infrared relation based on luminosity of galaxies is tighterand steeper but more likely to inherit a partial correlation from a tendencythat larger objects are also more luminous. The thermal fractions, radiospectral indices, and magnetic field strengths of the Magellanic-type galaxiesare between the values determined for spirals and dwarf galaxies. The confirmedmagnetic field-star formation and radio-infrared relations for low-massgalaxies point to similar physical processes that must be at work in allgalaxies.
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