Weinvestigate thin films of La0.7Sr0.3MnO3 grown on SrTiO3 in which bridges of 100 mu m long and 1 mu m or 300 nm wide (distance between voltage contacts was 25 mu m) were defined lithographically. In bridges of 1 mu m, we find the current-voltage characteristics to be perfectly linear (ohmic) over the full temperature range between 400 K and 10 K. Strong non-linearities however are observed for a 300 nm wide bridge in the temperature regime below the transition temperature. The non-linearities are present even when applying a high magnetic field of 9 T. (C) 2015 Elsevier B.V. All rights reserved.