  Temperature and current dependences of resistivity of bulk
La$_{0.75}$Ca$_{0.25}$MnO$_{3}$ sample grown by the floating-zone method were
studied using single ramp pulses of current. It is found that near the Curie
temperature $T_C$ the sample resistance depends substantially on current
magnitude. The observed features can be determined by inhomogeneous Joule
overheating due to mixed phase state of manganites near the
ferromagnetic-paramagnetic transition and percolation character of this
transition.
