  It is known that barotropic FRW equations written in the conformal time
variable can be reduced to simple linear equations for an exponential function
involving the conformal Hubble rate. Here, we show that an interesting class of
barotropic universes can be obtained in the linear limit of a special type of
nonlinear dissipative Ermakov-Pinney equations with the nonlinear dissipation
built from Chiellini's integrability condition. These cosmologies, which
evolutionary are similar to the standard ones, correspond to barotropic fluids
with adiabatic indices rescaled by a particular factor and have amplitudes of
the scale factors inverse proportional to the adiabatic index
